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  • OIL TO GAS FHW HEATING CONVERSION — ALL OF YOUR OPTIONS

    With the “Fracking Effect” of plentiful, relatively inexpensive natural gas (and oil) upon us, there is a continuing heating system conversion trend from oil, and justifiable in degree. However, this rush borders as all rushes do on becoming foolhardy. In the New England Region our magic number has been a $45-48 per barrel crude oil price, but it’s at best a “crude” one (please excuse the pun). We have seen a significant gas vs. oil crossover now in the past three (2016, 2017 & 2018) heating seasons. (Ref. our Heating Blogs.) It’s an easy sale to “play the numbers”, telling the customer what they want to hear. The typical scenario is an immediate “boiler swap” with perhaps a less than ideal economic resultant. But there are alternatives, depending upon your particular circumstance.

    If you are fortunate to have immediate, metered access to natural gas and your existing oil-fired system is “old enough to vote”, the choice is obvious — swap it! However if you have a newer oil system and it performs well except for the fuel bill, you have other options. Similarly, if you live in a non-natural gas area and are using propane, your incentive differs very substantially.

    Let us review these potential scenarios.

    Firstly, we must qualify your natural gas source AND it’s actual, delivered cost to you! It is a “distributed” fuel, like electricity and therefore has multiple service charges assessed. Always get an actual billing estimate as with any distributed fuel.

    Please refer to our additional, related Blogs from our site library for more detail. We will hyperlink as we proceed, but not necessarily all of them.

    The Installed Cost Premium of a Gas vs. Oil System must be considered and factored into any scenario. Gas systems are at minimum a 20% premium in our experience AND their life expectancy can be half or less of a cast-iron boiler system! Our blog “HIGH MASS vs. LOW MASS BOILERS – The Arguments”should be required reading in this regard.

    Recommendation: If you do not have natural gas access currently in the building, solicit and qualify its installed cost before further consideration!

    1. If it’s on your street the line extension may (or may not) be free as an incentive by your provider.
    2. If it’s down the street a ways there likely is a significant service extension cost up front. There may also be group incentives to extend and supply a neighborhood. This cost must be amortized over some service period. “Run the numbers.”
    3. Natural Gas (like Electricity) is a Distributed Fuel. As you know on your Electric Bill, the Kilowatt-Hour cost is burdened with service and distribution charges. Natural Gas is the same. Always solicit an ESTIMATED TOTAL GAS BILL from your provider!

    Read our blog USING A ‘HEATING COST CALCULATOR’ — CAREFULLY!….. For more detail.

    NOTE: We harp on using a “Heating Cost Calculator” for any project. “Gotta know where you are before you know where you’re goin’.”

    Another suggested “read” is our blog: HEATING FUEL SELECTION – FROM AN ENGINEER’S PERSPECTIVE

    Natural Gas (and Propane) Boilers (FHW) and Furnaces (FHA) are available in very different flavors, technically and efficiency-wise. The EPA assigned AFUE (Annual Fuel Utilization Efficiency) Rating can vary from the minimum required value of 85% to over 97% on Weil-McLain Products as an example. AFUE Rating must be obviously considered when making any system decision.

    Scenario 1: Older Oil Boiler (15 years or more), NatGas available on site, longer planned occupancy/ownership. Justify and replace with the highest efficiency unit available (Oil or NatGas) and enjoy the benefits. Note the substantial fuel cost premium of LP (Liquid Propane) vs. Oil if this is your only option ….. see also further below.

    Scenario 2: Newer Oil Boiler (under 10 years?), otherwise same as Scenario 1. Consider upgrading with a Gun Burner alone. Yes, there are several manufacturers of very high efficiency Gas Conversion Gun Burners. Among them:

    1. Carlin Combustion Technology.
    2. Wayne Combustion Systems Several Options.
    3. Midco International Residential Series.
    4. Additional Domestic and Foreign Suppliers.

    However, you must make an objective judgment as to the viability of this conversion. As an example the Weil-McLain Gold Series Oil Boiler has been around since 1995, still available and produced in quantity. It is an older “two-pass” design, 85% efficiency, with tight heat exchanger passages. A good candidate as are similar competitors’ models.

    A Gas Conversion Gun will be higher in combustion efficiency (up to 95%+?). Combined with the oil boiler that is efficiency-limited by oil’s chemical composition should provide you with very respectable boiler performance. We have no means of estimating this, but certainly the Gas Gun Manufacturer should have some history as a marketing tool. Ask!

    To expand our point, we regularly scour Craigslist for Cast-Iron Weil-McLain Gold Series Oil FHW and Steam Boilers as budget upgrades in our area (NH). We can save several thousand dollars by obtaining a well cared for unit for sometimes just above scrap value. Haven’t bought a lemon yet!

    Read our Blog: BUYING A USED BOILER? – CAVEAT EMPTOR (BUYER BEWARE)!

    Scenario 3: What about a LP (Propane) Conversion? The Fuel Cost Premium in our view has relegated propane to a “fuel of choice”. As of this writing, Propane is a 42 to 91% premium over #2 Fuel Oil regionally, using 95% and 87% Appliance Efficiencies (AFUE) respectively as a comparative. Otherwise the outlines in the prior Scenarios apply.

    Subsequently propane is primarily used for cooking, drying and seasonal or supplemental heating along with a wood, pellet or coal system in our rural area. Propane heated properties are therefore slower and lower sellers.

    There is however some relief that may be available to the propane user. Gas tanks are typically owned by the fuel dealer, locking the customer into his supplier. Conversely, oil tanks that are owned by the customer provide sourcing negotiation flexibility. Our customers advise substantial fuel purchase savings via direct negotiation. “Fuel Club” membership is another very desirable purchasing option that we personally employ.

    Commercial and particularly industrial propane clients typically own their storage tanks and contract with suppliers. There is no reason not to own your own tank, save two reservations:

    1. The initial cost of the tank and its installation.
    2. The manufacturing date stamping of the tank, the subsequent re-testing and re-qualification requirements. Tanks are date stamped (Mo.-Yr.) and must be re-qualified ten (10-12?) years after manufacture. (If you buy a used tank, check the date stamp! Don’t buy a dying or at worst a dead horse.)

    We have a local tank-owner client who advised us of a recent propane buy at an astounding price! He shopped aggressively and paid C.O.D. His purchase price was well below that of the fuel oil equivalent at the time.

    So, you off-the-pipeline propane gas users may have some hopes yet. Check them out.

    In closing, propane has historically been a premium-costed fuel. Having said this, it is conceivable that we may see a variant of natural gas emerge as a pressurized or liquefied fuel to challenge propane in the future. Stay tuned …

    Update: Read our Blog entitled “Oil Again The Cheap Heat in NH — For The Smart Buyer”. It documents the lower cost of oil vs. all other heating fuels @ a $32 a barrel this past winter. The approximate “break even point” with Natural Gas is currently around $45-48 a barrel. Fluctuations of both fuels (and others) should be qualified with a Current Heating Fuel Price Comparator, as we have noted in our Blog.

    Also reference our Delta-T ECM Hydronic (FHW) Heating Appliance™, bridging the Gas vs. Oil Heating Argument by applying the latest hydronic technology.

    Author’s Note: Updated 01/11/2019 P.D.M., Sr.


  • HEATING FUEL SELECTION – FROM AN ENGINEER’S PERSPECTIVE

    Heating fuel selection has become more than a casual topic in this currently tenuous economic situation, and likely to be an extended one. Unfortunately the picture is both clouded and distorted by the contemporary economic, political and media rhetoric. From an engineering perspective however the overcast is dissipating and the stars are beginning to show.

    As Sgt. Detective “Joe Friday” (Jack Webb) of the old TV Series “Dragnet” would retort upon questioning a witness, “Just give me the facts, Ma’am. All I want is the facts.” So here they are.

    From our Physics 101 Textbook: All physical matter exists in three (3) states: Gases, Liquids and Solids. Hold this thought.

    Our Chemistry 101 Textbook was divided into two (2) Sections: Inorganic and Organic Chemistry. Organic chemistry is dedicated to the properties of carbon, and in particular the C-H (carbon – hydrogen) bond and its chemical interactions. It is so important as to warrant its own science. There’s Carbon ….. and there’s everything else!

    Carbon compounds all occur in nature (predominantly in the earth) in all of its states as gases, liquids and solids. Due the energy content of the C-H bond they are all potentially direct heating fuels, or for the creation of other forms of energy, in particular electricity.

    What primarily differentiates the states of fuels is their “Energy Density”. (How much energy is contained in a comparable volume of material?) Therefore, as naturally occurring heating fuels they are:

    1. Gases: Natural Gases are the lowest density fuels.
    2. Liquids: (All Petroleum) Heating Oils are mid-density fuels.
    3. Solids: Coal is a mid-density fuel, comparable to oil, but solidified.

    There could be another category of “Renewable Solids”, made up of surface harvested fibrous materials such as Wood, Peat, Corn Stover, Peanut Shells, etc. These have much lower energy densities, somewhere between gases and liquids. You might consider these as “fuels of opportunity”, based on locales.

    None of these fuels as harvested below or above the ground can be directly converted into a heating fuel without further processing. They must be economically converted and moved to their points-of-use. This takes energy in varied forms, depending upon their specific fuel attributes.

    The Gases:

    Natural Gas is the predominant subterranean gaseous fuel and can be directly combusted for its heating value. Distribution and safety are the primary considerations.

    Having no smell, a trace gas must be added to all fuel gases for detection. That “stink” is a life saver! Gaseous explosions are memorable ones indeed.

    Natural Gas must be piped to its point-of-use. This piping infrastructure is large, extensive and expensive, supporting the movement of huge volumes of a very low energy density fuel over long distances. As a “distributed” fuel (similarly with electricity) these costs are burdened onto your energy bill, typically along with additional service and maintenance charges.

    IMPORTANT NOTE: Whenever doing fuel cost comparisons, you must solicit an estimated billing for Natural Gas and Electricity Service. The “Per Therm” or the “Kilowatt-Hour” (KWH) fuel unit cost IS NOT YOUR FUEL BILL! Locally (NH) we factor (multiply) by 1.5 to 2.1 seasonally for an estimated billing.

    Liquid Propane (LP), Liquid Natural (LNG) and Compressed Natural (CNG) Gases are concentrated, higher energy density fuel products achieved by composition, chilling and/or compression of gases into a tanker or tank for distribution. As such these become “delivered” products that are billed by-the-gallon or by-the-tank only.

    There is a significant amount of energy required to transform gases into usable liquid products, thus a much higher unit cost. Delivery costs related to tanker-to-site-tank or individual “bottle” deliveries are also factored into the unit cost.

    An on-site stored energy gas source must also be weighed, where applicable.

    All gases can be combusted very efficiently utilizing the latest “condensing” technologies. These are routinely 95+%. It must be accentuated however that the equipment investment is costlier than alternatives and must be factored.

    The Liquids:

    Petroleum Fuels (Carbon-based) being liquids have an inherent advantage over their gaseous or solid cousins. They can be pumped, poured, piped, tanked or transported with less energy and at substantially less risk. Only bulk barging or training of coal can compare, and then only to bulk use sites.

    Petroleum as extracted is a varying mixture of liquid and gaseous carbon-based products, readily separated by heating in a “Distillation Column”. Gases rise to the top and Tar sinks to the bottom. All are “skimmed” at their various levels. This is a relatively simple “first pass” process, but yields a ratio of products.

    The C-H based chemistry yields more. By introducing selective products under heat and pressure you can “polymerize” (chain them together) to make denser, heavier products or “fractionalize” (break them apart) to make lighter and gaseous products. Very high yields of usable fuel and lubricant products result.

    Heating Oil fuels combust efficiently in a modern, atomizing power burner. Peak is about 87% efficiency, depending both upon the appliance and the composition of the oil itself. Natural contaminants such as nitrogen and sulfur preclude higher values. Recent “Bio-Heat” Oil development, blended from harvested, carbon-based stocks will improve combustion efficiency somewhat. This along with “Fluidized Bed” and similar technologies promise even higher future combustion values.

    The Solids:

    Coal: Our discussion of C-H based solids must necessarily be limited to Coal. There are two (2) major derivatives, namely anthracite and bituminous, but energy-wise they are arguably similar. Functionally they process and handle much the same. Anthracite is the preferred variant in volume combustion applications, however.

    Coal requires considerable extraction and granulating energy, offset by the low material cost in situ. It bulk handles and transits readily and inexpensively, but its combustion characteristics relegate it to continuous-fire applications. Thus it predominates in electric generation. It handles very safely as well. When have you ever heard of a coal train catching fire?

    The Renewable Solids:

    Referring to our prior mention of these predominantly fibrous, harvested fuels, suffice to say that only wood is regionally viable and a great “sweat equity” fuel. It is also a natural by-product of our wood-harvesting industry. To quote that old New England adage: “Wood warms you twice”. We don’t foresee any significant deforestation resulting.

    Further, the quoted lower efficiencies for wood are aggravated by the need for moisture content control (air or kiln drying) and necessarily long and moderately controllable firing cycles. It is truly only a “fuel of opportunity”.

    The Current Heating Fuel Situation:

    By “situation” we mean what economical fuels are viably available and where are they located? The “what” and the “where” are inevitably linked.

    By any measure the United States is most bountifully blessed with all resources, with the least being not only our current heating fuels, but our future ones!

    The near-term picture is punctuated by our excesses of both natural gas and petroleum (oil) that have depressed heating fuel pricing dramatically. Despite a depressed economy a fervent effort is on to convert particularly oil-fired installations at all levels to natural gas, where available. We have within the past two heating seasons seen incremental fuel cost crossovers of oil and natural gas within the $45-48/bbl crude oil range.

    Natural Gas and Petroleum have become so plentiful in fact that we are net exporters of both fuels. The “World Price” of 4 to 5 times our domestic of Natural Gas in particular is just too good to ignore. It won’t hurt our trade imbalance either.

    It is no understatement that “fracking” (hydraulic fracturing) as touted in the technical journals is likely the most significant American Invention since the Computer. The world energy picture has changing dramatically, and for the good. This technology is applicable to both gas and oil exploration and production.

    We currently have about 50,000 miles of fuel pipelines operating in the U.S. The Canadian Athabasca (Oil Sands) extension known as the Keystone Pipeline is happening along with the Bakken Basin and others. Several U.S. and one (1) Canadian pipeline(s) are being reverse-flowed to support both this and the new Greater Mid & South West Fields. We are currently exporting some highly refined oil products to Europe from the East Coast. Delta Airlines recently purchased a New Jersey refinery for its dedicated jet fuel production. (Smart move!)

    We are now at oil parity and less subject to the fickle “World Oil Market” (OPEC). As we expand the ball game will change significantly. To accentuate this point: The current price of natural gas (energy-wise) is equal to an oil barrel-price of $15, or a gasoline price of less than $1.50 per gallon. Will we get there? Unlikely, but we are heading in that direction. The current barrel-price of $45 is expected to stabilize, barring world influence.

    Thus, the current and near-term heating fuel situation is substantially “business as usual” with a notable sag in heating oil pricing with natural gas applications expanding disproportionately. Heating oil cost is crossing over with natural gas, even as a delivered vs. a distributed product. Sharpen your pencils when you shop!

    Coal remains in plentiful supply! Without addressing the EPA Regulations, etc. it remains our significant electric power generation fuel as well as a selective heating fuel. It is a bargain where natural gas is not available, if you can utilize it. Note: We are now exporting coal to Asia and Eastern Europe.

    The “Crossover Fuel” Period: (the term is ours – and at our risk?)

    The disparity in natural gas supplies and pricing vs. the oil supply limitations and volatile pricing is breeding an era of “crossover fuels”. These will virtually all be based on Natural Gas in both gaseous and liquid states as a seed fuel. It will be combined with other gaseous, liquid and solid fuels to create oil product supplements for the transportation and in lesser degree the heating markets.

    This fuel availability phenomenon will precipitate a series of these products within a relatively compressed time period. None of these are “rocket science”, merely scaling existing technologies as market opportunities are presented. The following are just a few of these, but the likely leaders:

    1. Compressed Natural Gas (CNG): As a potentially more broadly applied transportation fuel, it is a real winner. Currently being used in Utilities Service Vehicles, its logical and economic extension to all mid-range (up to 200 mi radius?) fleet and service terminals (private and government) will have a major impact. The offset loosens up general oil supplies, including heating fuels. (This is also BillionaireT. Boone Pickens’ new pet project. He took an admitted $150M “hit” on now abandoned Windmill Projects. Looking to make his money back in a hurry we presume.)
    2. Oil from Natural Gas: There are several processes that can make oil from plentiful coal as well as lesser feed stocks. We are not familiar with the specifics excepting that plentiful gas next to plentiful coal seems to be a bench-marking enterprise.
    3. Alcohol from Natural Gas: Alcohol as a fuel has not been mentioned thus far. Its current notable application is as a beneficial gasoline additive. A C-H-O (Carbon-Hydrogen-Oxygen) Compound, its energy-density is less than oils, but burns cleanly and very efficiently. It is a superb racing and automotive (E85) fuel IN A SPECIFICALLY DESIGNED ENGINE! Ethyl Alcohol (Ethanol) is readily manufactured by process combination of natural gas and carbon dioxide (CO2) from the atmosphere. CO2 is that nasty (?) stuff that creates global warming (?). Estimated Cost: $1.50/gal.
    4. Alcohol from Coal: Referring to Items 2 & 3 preceding there is a proven, scalable process for producing alcohol from coal using natural gas. Estimated Cost: $1.50/gal. Note: Alcohol is not currently used as a heating fuel. The cost and energy-density vs. heating oil has not been advantageous. Secondly, the current heating oil process equipment would have to be modified for its use. A diaphragm-style fuel pump or similar device would need to be employed for atomization. (Alcohols are not intrinsically self-lubricating.) Otherwise there is no process reasoning to negate its use as a heating fuel.
    5. “Fuels of Opportunity”: This is the Etcetera Bucket that contains all of those development projects that ultimately produce oils or alcohols. There is a seeming plethora of these with few in scalar production. Notable are the alcohol producers:
      • Corn Ethanol Fuel Supplements– Gasoline additives (E10, E15 & E85) production by farm co-ops and independents.
      • Cellulosic Alcohols– Produced from fibers and by-products of surface agriculture.
      • Oil from Coal– High Temperature/Pressure Steam Injection into Coal Process. No cost-to-benefit analysis available. South Africa produces.
      • Etcetera – The list goes on.

    General Note: There may be a few winners, but a lot of losers in this alternative energy crap shoot. The Natural Gas glut will skew the results.

    Summary Notes on Current Heating Energies:

    1. Natural Gas will generally predominate, where available.
    2. The Oil vs. Natural Gas pricing gap has closed, returning to par for the next few years.
    3. LP (Propane) Gas will remain a “fuel-of-choice”.

    Near-Future Heating Fuels:

    Looking forward near-term in heating fuels is a simple matter. More of the same. There is nothing save the Natural Gas to Oil cost gap closure to talk about. You must also accept that common Heating #2 Fuel is close to Diesel Fuel and necessarily follows its pricing trends. (#2 Heating Oil is dyed Red to deter Diesel Tax Skippers from using it in their cars and trucks. Fine resulting when caught!)

    The giant strides in efficiency made in the past ten years or so in heating appliances will be tempering. There’s just is not much more to be had in particular with gas efficiency to play with. Oil efficiency continues to address its composition problem.

    Recommendation: If you’ve been procrastinating, waiting for that world-beater boiler or furnace to appear, don’t hold your breath any longer. Invest in that 95% Condensing Gas or 87% “Triple-Pass” Oil Boiler. Stop “throwing good money after bad.”

    The Future Heating Fuel: Nuclear-Generated Electricity

    Surprised? You shouldn’t be. Electricity is the simplest and most efficient means of generating, distributing and utilizing energy. Problem is that we don’t generate it efficiently enough. We do a fair job with hydroelectricity and maybe geothermal, then we get loose. But even these are not really good enough.

    Back to Energy Density. The C-H Bond energy potential is the basis for all of our fuels. The energy-density of a Nuclear Fuel is 1 to 2 times 10 to the 6th power or 1-2 million times that of the C-H Bond! So why don’t we have cheap enough electricity? The wrong nuclear technology. We developed and then abandoned the correct one in the 1970’s in favor of uranium and plutonium based processes – to build bombs with their by-products.

    Thorium LFTR Reactors are being aggressively developed by Russia, China and India, with our technology! We must have them to project our Medical Isotope, NASA Deep Space Programs and as a DOD Modular Power Source at minimum. We’re looking at electricity costs of less than $0.01 (cents) per KWH! Check your current electric bill.

    For your Homework, read up on Thorium. It’s our future.

    Last Edit: 09/07/2017 pdm


  • DOMESTIC HOT WATER (DHW) GENERATION – YOUR OPTIONS

    We just returned from a hardship “no heat” service call. These folks are obviously up against it economically, as are many these days. However they recently substituted an electric water heater for their boiler immersion coil to generate domestic hot water and hopefully reduce their summer fuel bill. Now they are concerned about the increase in their electric bill as a consequence.

    This brings up the timely subject of options available in DHW generation. Please refer to content in our other blogs, specifically related to energy source selection, tempering tanks and using a Heating Cost Calculator. For the latter we use the NH OEP Heating Cost Calculator at http://www.nhclimateaudit.org/calculators.php. There should be equivalent calculation tools available for your region.

    Heating Cost Calculators don’t lie. They provide a unit energy cost per Million BTU’s for each fuel. You should apply an appropriate AFUE (Energy Efficiency Rating) for your or the best competing appliance by fuel type to get an accurate comparison.

    By calculation DHW heating fuels from lowest to highest costs are: (NH Region)

    1. Natural Gas – Rate factored by 1.5 to 2 for actual billing. (Divide total fuel billing by actual fuel charge for factoring.)
    2. Fuel Oil
    3. Propane
    4. Electricity – Must be also factored for actual billing. Ours is 1.85. (Varies significantly by Provider & Region)

    Note: 1&4 are “distributed fuels”, necessarily incurring varied pipeline and distribution service costs.

    Natural Gas has been historically the most efficient fuel for both heating and DHW generation vs. fuel oil until recently. A very rough crossover is a $45/bbl Crude Oil Price. Local fuel market variations and appliance installation costs must be considered. Propane, a manufactured fuel, is by comparison a significantly higher cost product. This is unfortunate in that they utilize the same appliances (with minor modification) with similar efficiencies. Propane fuel cost is a killer!

    Fuel Oil and Gas Heating Appliances provide the same function, however differing significantly in configuration to accommodate their particular combustion characteristics.

    Electricity despite its extremely high energy efficiency is offset dramatically by unit cost. Electric Water Heaters are enticingly priced, too. Too bad.

    We are considering only the intermittent combustion fuels (oil and gases) in our analysis. The continuous combustion fuels such as wood, coal, etc. suffer by nature to being very inefficient DHW generators. This is not to allow that these fuels fired in boilers can provide seasonal DHW to Indirect Storage Heaters or coupled to a central boiler with an immersion coil. Although increasing in rural popularity, they don’t represent a significant market segment to date, nor likely will they ever.

    Gas and Oil Combustion Appliances are limited to Boilers and Water Heaters. Their configuration options are similar with the exception of the Gas “Demand” Water Heater and are as follows:

    1. A “stand-alone” (dedicated) Oil or Gas Water Heater. These are a virtual necessity when the central heating appliance is Forced Hot Air (FHA). The stand-alone Oil-fired Hot Water Heater has suffered from poorer fuel efficiency by design and has been limited to high demand users such as restaurants, etc.
    2. The Gas “Demand” Water Heater – A unique, hang-on-the-wall device, it stores no heated water but fires only when DHW flow demand is detected. It is very sensitive to water conditions, including acidity, contamination and lower delivery temperatures.
    3. A Central Heating Boiler with an Immersion Coil therein to create DHW.
    4. A Central Heating-only Boiler coupled to an Indirect Water Heater (Super-insulated DHW Storage Tank). Provides higher efficiency in both heating and DHW generation. Significantly increasing in popularity.

    The Gas-fired “On-Demand” Water Heater has a distinct DHW market application, subject to several limitations:

    1. They are “pricey” relative to other options.
    2. Initial DHW delivery is mildly delayed during warm up.
    3. Long cycle demand capacity reduces with supply water temperature decrease (colder water from source).
    4. Annual chemical treatment to control sedimentation is required to maintain performance.

    Note: Both the Gas “On-Demand” Water Heater and Boiler Immersion Coil Systems mentioned can benefit from a “Tempering Tank” placed in line with their water supplies. (Reference our prior blog on these.) It’s a non-insulated accumulation tank that allows water to acclimate to ambient (room) temperature before entering the DHW heating device. Increases heater performance significantly by temperature and delivery maintenance over total cycle demands.

    Otherwise, Indirect Storage Heaters are the path to efficient DHW generation and storage – regardless! They compliment lifestyle variations and usage patterns when coupled to an efficient heating-water-only generating device, commonly referred to as a “Cold Start” Boiler. It fires ONLY when area heating or DHW recovery is demanded. Otherwise they revert toward ambient temperature, saving significant “standby losses” when not in use. There are several options to “getting there from here”, depending upon your situation.

    1. Purchase a High-efficiency “Heat-only” Boiler and Indirect Water Heater as a package and be done with it.
    2. You can convert your existing Immersion Coil System Boiler to a “Cold Start” Type by:
      • Changing your Master Aquastat Control to a “Cold Start” Unit
      • Adding an Indirect Water Heater with its own circulator or valved zone.
    3. Couple an Insulated DHW Storage Tank to your current Boiler Immersion Coil with a POTABLE WATER CIRCULATOR ONLY (Stainless or Bronze) and Temp Aquastat Zone in the loop. Substitute a “Cold Start” Master Aquastat to convert your boiler to a “Heat-only” as in Option 2.
    4. Do Item 3, but convert a good 80 Gal. Electric Hot Water Heater into a Storage Tank. Strip its wiring and utilize the upper, internal Thermostat Switch as a DHW temp control. Note: This last option is the “Cheap Trick”. It costs significantly less to install, despite the pricey circulator requirement. DHW piping is typically run in parallel with the immersion coil with a flow check function.

    Whenever employing ANY Storage Tank for DHW, place a Thermal Expansion Tank in-line on the cold water supply line! Heating cold water expands it, creating pressures well above the supply pressure and potentially bursting the system. This is particularly evident in municipal or well supplies where there’s a check valve in the cold water service. Cheap insurance!

    So, using the appropriate fuel costs from a Heating Cost Calculator and reviewing your current or planned appliances, plan your Heating and DHW Systems together for best efficiency.

    Last Edit: 06/24/2017 pdm


  • MAXIMIZE HEATING EFFICIENCY WITH A SINGLE ENERGY SOURCE

    Optimization of heating efficiency first requires determining your specific requirements. In general terms there are two or more distinct heating energy uses:

    1. Area Heating – Warming occupied areas fully, or selectively as living habits occupation or use may demand.
    2. Domestic Hot Water  (DHW)– Heated, potable (drinkable) for baths, showers, laundry and personal consumption.
    3. Special Uses – High temperature power washing, sanitizing, etc. (Refer to prior blog.)

    All of these requirements can ideally be met by using a hot water boiler system as a single, central source but the question arises of how to accomplish this efficiently. Specifically, varied heating demands that may range from continuous (?) DHW to very occasional (seasonal?) and selectable area warmth can become a challenge, particularly economically. However occasional demands can “lighten your wallet” to execute and maintain. Let’s address this problem systematically.

    Arguably the most important decision has to be your heating fuel selection. We cannot overemphasize this and the use of a Heating Cost Comparator to define your choice. (See our other blogs.) The standard unit of measure is the “Cost per Million BTU” expressed as a dollar figure. We use the NH-OEP Calculator for our area usage, but similar ones are available online. Use your current or projected new heating appliance efficiencies (AFUE) to get an accurate calculation. New Gas (Natural or LP) AFUE’s are typically 95% for top end (condensing) boilers and 87% for Oil Triple-pass boilers.

    The current and foreseeable heating fuel choices have become quite obvious in the northern climates:

    1. Natural Gas (where available) is the accepted baseline. But BE CAREFUL! Natural Gas is a “distributed fuel” (through a pipeline). Your actual bill will be considerably higher due to service and distribution costs added to your actual therm usage. Get a billing estimate from your gas provider first! (Our local multiplier is up to 2.0 or 100% added for your actual natural gas billing costs.)
    2. Heating Oil is the predominant fuel where natural gas is not available.
    3. Liquid Propane (LP) Gas is another option along with oil where natural gas is not available. LP has been used predominantly for domestic cooking and somewhat for DHW generation. As an area heating and DHW fuel it has traditionally been up to a 100% premium over oil. It is a heating option of choice in our experience.

    Note that solid fuels (wool, coal, peat, waste, etc.) have been purposefully omitted from this discussion. Insurers typically disallow continuous firing fuels using interior combustion equipment. External or “outdoor boilers” are “zero pressure” and require a “plate exchanger” interface with an internal power fired system to assure continuous heating maintenance. Verify these statements and weigh potential penalties for your particular situation.

    Consumers predominantly identify their area heating options as Forced Hot Air (FHA) Furnace or Forced Hot Water (FHW) Boiler Systems. Similarly DHW options as Electric, Gas or Oil stand-alone Water Heaters or from an immersion coil within a boiler. So therefore we usually find the typical FHA System with a stand-alone DHW Heater as a combination. FHW Systems usually provide DHW from an internal Immersion Coil, as previously noted. Currently we are seeing the emergence of the Indirect Hot Water Heater, supplied by a boiler as the efficiency choice.

    But in fact our heating options are more extensive. They include:

    1. Air Handler– A FHA Furnace without a fuel-powered heating source. Instead it has an internal large radiator (heat exchanger) that is externally supplied with energy from a FHW source (boiler).
    2. Unit Heater– A radiator with fan, typically found as an overhead heater in a garage, warehouse, etc. There are also variations of these with provisions for attaching ducting – otherwise similar to an Air Handler.
    3. Plate Heat Exchanger– Basically two (or more) mutually integrated radiators allowing the interchange of heat from varied sources. Source variation attributes may be pressure, temperature, flow rate(s) and composition. Their composition may be aqueous (or not) and adjusted for properties such as freezing and/or boiling resistance.

    Utilizing these latter devices allows us to employ higher efficiency or lower cost hot water generation sources (or both) for all our area and DHW heating requirements. We respectfully suggest that where a single, efficient energy source is desirable or necessary for continuous demand a FHW boiler should be employed. Further, that this source then be applied to all your structure’s heating demands with all the resources detailed within.

    The unmentioned physical fact is that utilizing water as an energy conductor is inherently and significantly more efficient than air. Thus an HVAC System (air heating/cooling) is less efficient than a hot water boiler (heating) coupled with an air handler (cooling) combination. This can be witnessed in their assigned AFUE values.

    So, let us wrap it up by considering some common scenarios for our FHW boiler system source:

    1. A Central HVAC (Heating,Ventilation & Air Conditioning) System Upgrade.

      • Upgrade the existing FHA Furnace with an Air Handler, if desirable, or
      • Install a FHW Heat Exchanger (radiator) into an existing FHA Plenum, plumb and rewire as necessary.
      • Install a “Chiller” in the Hydronic System to provide an A/C source.
    2. Existing or planned FHA System Upgrade – Same as 1. without A/C.
    3. FHA installation into a seasonal, incremental, unheated area or as an expansion.
      • Install an Air Handler or Unit Heater variation to suit.
      • Where freezing protection is desirable, employ a Plate Heat Exchanger with anti-freeze as necessary.
    4. Use a Plate Heat Exchanger to couple “incompatible” secondary heated water sources such as exterior wood & coal boilers, solar & geothermal loops, etc.
    5. In all cases, move to an Indirect Water Heater for efficient DHW generation.

    By the way, these new high efficiency boilers do not necessarily need a chimney. Condensing Gas Boilers typically use PVC pipe for venting and Triple-Pass Oil Boilers with Pressure-fired Burners can use a direct exhausting vent kit.

    Have we run you out of options yet?

    Last Edit: 10/18/2018 pdm


  • CONVERTING A STEAM HEATING SYSTEM TO HOT WATER – THE WHYS AND HOWS

    Steam Heating Systems were the Cadillac of heating options for residential applications for about a century. Pricey, tending to be a bit fuel-thirsty (regardless of the fuel used), they were extremely simple, durable and provided a superbly comfortable heated environment. Economics have gradually forced steam heating into the commercial and industrial process realms alone. So where do you go with that residential steam system? It depends upon your goals.

    When do you stay with steam rather than change over to hot water or some other heating form?

    1. If you have a nice, period home that suits your needs excepting to lighten up on your wallet a bit, just upgrade the boiler to a modern, high efficiency unit. Older boilers typically are large, with open heating passages to suit both wood or coal fires that when upgraded to gas or oil result in very poor fuel efficiencies. Presuming the system piping and radiators are serviceable there is little incentive to change over the entire system. (Steam heating distribution is arguably more efficient than hot water!)
    2. Similarly, if you like those decorative radiators that warm your hands, food, dry clothes on, etc. and take up less footprint and wall space than hot water baseboard, think again.
    3. If you plan an addition or heated area extension and envision running steam piping everywhere to heat it, there is the little known and utilized steam boiler “bottom water” forced hot water heating option. Circulating the lower water below the steaming chamber (top of the boiler) provides extended heating system flexibility. Furthermore, forced hot water extends capability to attics, garages and additions with baseboard, Unit Heaters (fan forced radiators) and Air Handlers (a ducted FHA Furnace with an internal radiator that heats your hot air vs. using a gas or oil fuel source). You must however convert zero-pressure steam water into approx. 15PSI heating water for circulation to new radiation. A correct plate-to-plate heat exchanger is required and circulation both from the boiler and to radiation added. A separate water supply source and an expansion capability must be provided for the pressurized heating water circuit as well. Note: Remember to size your now “two-state energy” Steam/Hot Water Boiler accordingly.

    There is an interesting “middle ground” where you can convert your existing, newer steam boiler to hot water operation while keeping those aesthetic steam radiators. You must however replace all the old steam system piping in doing so. Steam radiators work well with hot water, but at moderately reduced heating (temperature) capacity. More importantly is the higher water volume content of steam radiators and how to supply them properly for even distribution.

    Referring to our separate blog on FHW Heating Loops, you can’t pipe cast iron steam radiators in series and get even heating! Even a split loop will not work but for a couple of radiators at best.  The only effective option is the mono-flow loop system, branched for each radiator. All will require increased piping and circulator capacity.

    Despite the challenges, converting steam radiation provides some attractive opportunities, heating-wise.

    1. You maintain your prior heated area aesthetics and functionality with few perceptible changes.
    2. You can now re-pipe and “zone” the prior area with multiple thermostats, even down to individual room level if you desire.
    3. Obviously you can add additional heated areas (zones) as well.

    Fully converting a steam boiler to hot water operation and then replacing or adding all heating distribution components is the last and most complete option. Scenarios:

    1. You have an excellent steam boiler with an economic incentive in mind. If you just wish to swap this unit out for your existing, inefficient or failed FHW Boiler as a one-for-one, be careful. Make certain that the conversion components and labor (as applicable) justify the changeover.
    2. Changing your existing, older steam boiler to FHW in our view is questionable. You are trading off operational efficiency against upgrade costs.
    3. Steam Boilers typically and Weil-McLain Steamers (our expertise) in particular have several advantages over their sister Hot Water Boilers. The front and rear sections are notably heavier and bulkier, containing more cast iron and water that can contribute to durability and theoretically capacity. Can’t speak for other manufacturers, but the Weils are heavier and tougher. Check their Specifications. Also if you are using a DHW Coil (immersion coil in the boiler to generate your domestic hot water), steam boiler coil(s) have nominally higher capacities and larger (Weil-McLain) boilers sometimes have two coils, or provisions for them for greater DHW capacity delivery. Check.

    A recent phenomenon is the Outside Wood Boiler. You know, that thing that sits beside a house that looks like a Metal Garden Shed with a Smoke Pipe sticking up out of it and a woodpile alongside. They are typically owned by rural folks that have a great wood supply and don’t mind tripping through the snow to keep themselves warm. These boilers are also “zero pressure” systems. They must be adapted to a pressurized FHW System through a Plate-to-Plate Heat Exchanger, utilizing circulators and controls. (You must maintain constant electric service to these systems or it can get exciting and cold, or both.)

    Coupling an Outside Wood Boiler to a Steam System is dubious at best. The only deliverables in this scenario are preheated boiler water that must be then fired and converted into steam by the central boiler, but which can also provide DHW through its internal coil (if equipped) or by an Indirect Water Heater (Insulated DHW Storage Tank) as an option. It just doesn’t make sense except to generate a lot of Domestic Hot Water. Therefore, in order to utilize the Outside Wood Boiler effectively you must do a complete steam boiler conversion (or a hot water boiler substitution) with the appropriate scenarios as previously detailed. There is no “easy road to glory” on this one.

    So procedural, to convert a steam boiler to forced hot water operation you must:

    1. De-plumb all iron and other piping right to the boiler. It must be “bare” as we say.
    2. Remove all of the electric components and associated wiring.
    3. Remove the Boiler Jacket (usually sheet metal) and place aside for reassembly.
    4. First, locate and substitute a 30 PSI (FHW) Pressure Relief Valve for the 15PSI (Steam) Valve. VERY IMPORTANT! Forget, and you’ll get wet — and surprised!
    5. Remove the Water Sight Glass, LWCO (Low Water Cut Off), Pressure Switch, etc. (Clean off the front of the boiler, in other words.) Dope and plug all affected boiler taps.
    6. Check Immersion Coil (DHW) Gasket(s) and Blanker Plates for leaks. Fix them.
    7. The smart guy plugs, fills the boiler and pressurizes it to 30 PSI (until the Relief Valve opens) and then checks for ANY LEAKS! Remember, steam boilers operate at about 0.5 to 5 PSI in use. You may have sectional leaking issues and not see them at that pressure. Sectional leaks between boiler castings are usually catastrophic. Stop and rethink your options. But, assuming it passes …..
    8. Find the manufacturer’s boiler piping diagram and locate the preferred aquastat front tapping and insert the appropriate “Spud Well” to receive the aquastat.
    9. Reassemble the boiler jacket and provide the opening for the Aquastat “Spud Well”.
    10. From the Manufacturer’s Hot Water Boiler Manual, identify the control components and hardware necessary to refit. Present this info to your Qualified Heating Engineer or Technician.

    Pay particular attention that your Master Aquastat selection compliments your application. There are several operational options available and should be qualified prior to final selection. Our preferred is the Hydrolevel “Fuel Smart” 3250-Plus Aquastatwith “Electro-Well” for all conversions.

    You now have a tight boiler ready to reconfigure for your application. Your further risk is minimal, save a hot operation leak(s) that may or may not be seal-able. Now consult and utilize a knowledgeable source.

    Be mindful that in converting any steam system to forced hot water you reduce the capacity of that system by 10% or more, if that is a consideration. Steam operates at a significantly higher system temperature in its vapor state than can be safely achieved with heating water safely below its boiling point.

    It may be implied from the above that we discourage steam to hot water boiler conversions. We have done it very successfully, once with an almost new Weil-McLain Gold Steamer and we’ve never been back. Do your homework!

    The option of acquiring a near-new FHW boiler instead of converting your steamer, particularly with the preponderance of on-going fuel conversions can also make very good sense.

    Hope this has helped you assess your particular situation.

    Updated: 11/28/2018 pdm


  • THE “POWER VENTER” – “Throwing Good Money After Bad”

    “Throwing Good Money After Bad” is a popular expression that is deservedly applicable to the “Power Venter”, a heating accessory device that enhances a poor chimney’s performance or substitutes for a chimney, depending upon its configuration. Proposed and presented as a “problem solver” it is in our view a “Band Aid Solution”, and deserving of ridicule.

    As a policy we do not install or service Power Vented Systems. One of our collaborators has in fact “cleansed” his entire 1000+ service customer database of all of these devices. “Don’t need the aggravation” is his comment. Recently however we’ve had two incidents that prompted this discourse. One was “doing a favor” for a dear friend with a hardship to discover a Power Vented Weil-McLain Gold Oil Boiler badly in need of maintenance. The second was an invitation to view a customer’s newly pre-built, purchased home only to discover a local plumber’s handiwork, i.e. a non-Energy Star (new?) boiler with the wrong gun affixed — and a Power Venter.

    Situation #1: This is a typical older period local plumber (and not a very good one) budget installation that has survived 15 years of erratic operation. The boiler piping was so improperly installed in fact as to possibly warrant a future addendum to our blog entitled “Plumbing Guys Plumb, Heating Guys Heat”. The Power Vent required mechanical repair and was by current Building Code non-compliant. Primary Power Vents are typically shoved through the box joist of a building near the heating unit as an expedient, in this case without regard for current Code Requirement that the intake and exhaust of a heating appliance MUST be 12 to 18 inches above the anticipated maximum winter snow level. This one certainly wasn’t.

    Situation #2: This is obviously another corner-cutting special, but new and supposedly to Code. Two counts on this one, i.e. a non-Energy Star Compliant Heating System (built from old stock, separate components?) and the same snow level height venting violation as above. Shame on the Local Code Compliance Officer!

    The Power Venter is by definition an energy consuming device, not only in using electricity to drive a blower, but by also forcing ambient heated air out of the structure to induce draft and cool down the exhaust for expulsion. The resultant negative pressure on the building pulls external (cold) air into while driving already heated air out – a “double whammy”. The argument could be made that in a modern, “tight”, energy efficient home the Power Venter air supply should be external for functional operation.

    By specifying modern pressure-fired or “condensing” heating systems the need for the Power Venter is gradually going away, thankfully! There is no longer a need for a chimney, technically speaking, unless it is convenient and likely pre-existing. Replacing it is either low temp plastic piping on “condensing” gas or concentric metal venting on oil appliances for both combustion air intake and exhausting.

    Note: In some existing cases there may be the opportunity to upgrade with a pressure-firing gun to do away with the powered venting device. Consult with your heating engineer or a well qualified technician.

    In summary, comments to the heating system customer.

    1. Older and existing homes with Power Venters:
      • If you’re buying – beware! Your system operating cost will be higher in utilities and maintenance.
      • If you’re upgrading – factor the Power Venter going away and substituting a high efficiency pressure-fired or condensing system. A “win-win,” in both fuel and operational efficiencies.
    2. New homes:
      • If buying, a Power Venter should not be there. If it is, asks the hard questions. Check your Codes.
      • If specifying a new home, use your Power Venter Eraser. You’ll never regret it.