• Tag Archives Weil-McLain Ultra
  • SIMPLE, DURABLE, EFFICIENT FHW HEATING ….. PERIOD!

    Our Motto is“Simple, Durable, Efficient FHW Heating ….. Period!”. Boilers On Demand LLChas achieved this seemingly noble objective by fully integrating Advanced Taco Delta-T ECM Hydronic Distribution Technology into Forced Hot Water (FHW) Heating . The unstated result of our“Convection Enhanced Delta-T ECM Hydronic Heating Appliance” (Patents Pending – USA & Canada)development is it being highly cost-effective as well. Can we “have it all”, so to speak? Let’s look at our effort in further detail …..

    Hydronic (FHW) Heating to the layman and consumer has always had a certain mystique, evidenced by witnessing a tradesman or plumber configuring a system, piece-by-piece into a seeming maze of piping and components. The results vary from the mundane to aesthetically impressive, but we must realistically note in fact that the hydronic performance of any system is less than ideal. The residential and light commercial heating markets in particular have not had the tools nor the general expertise to optimize a hydronic heating installation. Consequently the end user has suffered with an over-installed, under-performing, energy-consumptive system over its lifetime ….. knowingly or not!

    Note: We can’t excuse our like personal participation for now sixty (60) years in hydronic heating. Our guilt is shared ….. but no longer!

    Now a true “hydronic revolution” is upon us, not yet generally known and even less appreciated, nor applied. Hydronics have thankfully been somewhat forgiving to all of us applying it, but now there’s a new day, and a new benchmark.

    By explanation, there are three (3) basic elements to hydronic heating: Energy Creation, Distribution and Radiation. Put more simply:

    1. A Hydronic Boiler to create energy by burning a fuel, as efficiently as possible.
    2. Moving (distributing) heated water to points of use with “pipes and pumps” (circulators).
    3. Warming an environment by passing air over hot piping, as simply and effectively as possible.

    We have progressed quite well in creating and utilizing energy via boilers and radiation, but that is where it has stagnated far too long. Given the limitations of fixed or selectable speed circulators and valving we have managed without addressing the true potential of improving hydronic distribution efficiency to complete the heating equation. The intelligent, variable speedDelta-T (ΔT) ECM VT2218 00e Series Circulatorby Taco Comfort Solutions® has changed it all ….. and none too soon!

    We have been experimenting with Taco® Variable Speed Delta-T VDT’s, “BumbleBees”, Viridians and now 00eSiries ECM Circulators for years, utilizing them as direct substitutes for their fixed-speed predecessors. They have worked particularly well as radiant zone circulators as our fellow tradesmen have also discovered. The Taco BumbleBee® in particular has gained trade notoriety both by its appearance and performance. However, our personal technical efforts have gone well beyond the obvious in pursuing a dedicated boiler system circulator application. It has neither been promoted nor seeming anticipated, yet its implications are very significant when achieved.

    Utilizing a Delta-T, and in particular an ECM (Electronically Commutated Motor) based circulator as a single, dedicated system hydronic “distributor” offers near-ideal efficiency potential. We slogan it as“putting an ‘Automatic Transmission’ on a boiler”. It greatly simplifies both near-boiler piping and control complexity, but must necessarily possess several operational attributes:

    1. First and foremost is reliability! A dedicated (single) system circulator failure is a potential “show-stopper” after all.
    2. Performance Flexibility. It must adapt to and accommodate all system energy demand patterns with minimal, if any effect.
    3. Accommodate an Indirect Water Heater as a prioritized and an incrementally higher energy demand accessory.
    4. Significantly improve system efficiency and performance while reducing energy requirements, both fuel and electric.

    Zone Valves are a necessary compliment to manage individual zone demands when using a single circulator. New generation valving and in particular the Taco Zone Sentry® Valve provide outstanding performance and value with self-diagnostics. The “Zone Sentry” in fact delivers three times the heating capacity of its popular “Heat Motor” predecessor, and uses dramatically less power. Combine these with its physical packaging attributes the “Zone Sentry” provides a unique configuration opportunity further addressed in this writing.

    The hydronic distribution function is composed of two elements:

    1. “Near-boiler piping” as generally referred includes circulators, valves, air elimination and expansion devices that prepare and present heated water or “hydronic energy” to points-of-use.
    2. Distribution piping that extends and presents this heated water energy to radiation components.

    We offer that considering these two distribution tasks without differentiation or distinction is fundamentally flawed, and yet is standard trade practice. As initially stated, Delta-T Distribution Technology changes this assumption, and dramatically! Consolidating hydronic flow within a single, intelligent system level circulator packaged with complimentary, intelligent zone valves packages into a true, efficient FHW Heating Appliance. Further, “hydronic convection” (gravity heating), the natural attribute of heated water to rise and convect within distribution piping is idealized as well. Witness the need to install “flow-check” valves in conventional systems piping, into circulators or using properly sited zone valves to control convection (gravity) heating. By incorporating natural convection total circulation energy is measurably reduced beyond that of Delta-T. A simple analogy would be “like paddling your canoe with the current, rather than against it”.

    Hydronic convection performance is at the core of our Proprietary Near Boiler Piping System. Included as a standard, recommended option for idealized system and DHW (domestic hot water) creation efficiency is an Indirect Water Heater(the HTP SuperStor Ultra Series). Close-coupled within our near-boiler piping, its integrated supply architecture becomes a physical, gravity flowing extension of boiler capacity, particularly in circulator fail-mode operation. Yes, we had a “fluke” 1st Generation Taco Viridian® VT2218 failure on our “Beta #3” site that was not discovered for an estimated 2-3 days of heating operation. DHW generation was never affected!

    Ideally complimenting our hydronic system is the highest-mass boiler for its rated output (the Weil-McLain UO Series), extending system energy storage capacity and potential fail-mode convection performance. Its supply and return rear porting compliment near-boiler piping by compactly and efficiently packaging all hydronics within its footprint plus an approximate 1 ft. rear piping and exhausting space. Adding the Indirect Water Heater uses under 12 sq. ft. of combined space, up to 2/3 less than a typical currently installed system while reducing system valving and near-boiler piping by up to 1/2. Integrating with domestic all-steel piping, malleable fittings and brass/bronze valving compose a free-standing system architecture of innately superb strength, chemical resistance and field proven longevity.

    Now applying our paralleled “High-Tech” Manufacturing Process expertise to Hydronic Heating, we have modularized, value engineered, methodized and tooled our Delta-T ECM Hydronic Heating Appliance to include several additional components in our Intellectual Property Protection (Patent Pending) Submission. Our cooperating customers on multiple “Beta Sites” are also providing us valuable data to optimize our system design and performance with the goal of providing an unbeatable cost-performance product.

    Taco Comfort Solutions® publishes that its Delta-T ECM VT2218 00e Series Circulator provides up to 15% fuel and 85% electrical power reductions in applications. We certainly concur! Our dedicated VT2218 system circulators are using 8-13 Watts in heating maintenance mode. Cold system warmups begin at 25-35 Watts (half the rated power) then reducing toward acclimation temperatures.

    At the extreme of our experience is our “Beta #1″ Site upgrade, badly mis-piped with three hidden, seriously undersized 1/2” radiation zone supplies & returns that exhibit high head pressures (obviously). A pre-existing integral IWH is also under-sized piped, adding to delivery issues. Yet, this system cold starts @ 65 Watts, decreases rapidly to 35 Watts, then slowly acclimates to 22-25 Watts running. (A single Taco® 007 draws up to 80 Watts by comparison. It had four operating three heating and the IWH zones.)

    Additionally by using the High-Mass Weil-McLain UO Series (Oil) Boiler(s) we see system operating temperatures lowering to 132-140º F, regulated by its integralHydrolevel “Fuel Smart” HydroStat® 3250-Plus Aquastat. System demands are readily “cushioned” by the thermal mass provided in the total system architecture. It responded very positively to the prior noted prototype system circulator failure, ramping up system temperature toward maximum with zone duty cycle duration detection & response, maintaining radiation heating in degree. Boiler burner cycles are infrequent and brief, further reducing equipment maintenance levels while extending system operating life.

    We have more recently offered the appliance-specific Carlin EZ-PRO Gas (NG&LP) vs. the Beckett NX Oil Burner in the Weil-McLain UO Boiler. Now it’s a Universal Hydronic (FHW) Heating Appliance! Change fuels ….. swap the burner only!

    Total Hydronic  (FHW) Heating System Efficiency is  the AGGREGATE  of Boiler AFUE, Delta-T ECM Hydronic Distribution & Radiation Efficiency Gains! We further claim that the reduced operating system temperatures and hence stand-by losses of the very high mass Weil-McLain UO Boiler further increase overall efficiency. Thus we can confidently claim the highest efficiency heating system available!

    System Comparison

    “Conventional” FHW Heating System         vs.         The Delta-T ECM Hydronic System

     

    Identically Specified 100KBTUH, 2-Heating Zone + IWH, Oil-Fired Systems

     

    Attribute"Conventional" System"Delta-T" SystemComments
    Boiler TypeWelded Steel Plate (Example Unit)Cast Iron "Triple-Pass"15 years +/- vs. 30 Years +
    Boiler Weight270 Lbs.625 Lbs.Very High Mass - Durability
    Oil Burner TypeVarious OfferedBeckett NX (Pressure-Fired)Flexible, stable operation
    Gas Burner TypeFixed, Appliance-SpecificCarlin EZ-PRO (NG/LP) (Pressure-Fired)Appliance-Specific Interchange
    CirculationMultiple Fixed Speed Circulators onlyA Delta-T Variable Circulator w/ Intelligent Zone Valves>/ 15% Fuel Savings
    >/ 85% Electrical Savings
    Piping/FittingsCopper (Typically)All Iron & Cast ConstructionSuperior Strength/Durability
    Indirect Water HeaterVarious Mfrs. & TypesAll Stainless Steel OnlyA Lifetime of Service
    Floor Space UtilizationInstaller-dependentOptimized Package DesignMinimum Space Requirement
    Energy PerformanceInstaller-dependentOptimized Energy DesignPeaked Hydronic Efficiency
    Component SourcesU.S./Foreign Mix (Typical)"All-American" (US/Canada)Quality and Serviceability
    Installed Cost (Oil example shown)"Over $10,000" (Oil, as shown)$7,000 (Oil, as shown)Price, Performance, Value

    To Summarize:

    Taco® Delta-T ECM Hydronic Distribution changes everything! The “Plumber’s Playground” of conventional, inefficient hydronic distribution piping “free expression” is gone as well! We must now look at Hydronic (FHW) Heating in totality, no longer as a an aggregation and assemblage of parts by personal preference. Technology has provided we heating guys with some new working tools. Let’s learn how to use and apply them well!

     Author’s Note: Updated 10/01/2018


  • “PROGRAM” YOUR INDIRECT WATER HEATER (IWH) FOR SYSTEM EFFICIENCY

    An Indirect Water Heater (IWH) driven by an efficient hydronic boiler is the acknowledged cost-effective method for domestic hot water (DHW) generation. However, installing an IWH as a stand-alone (dumb) heating accessory can limit its potential and in fact reduce your overall annual heating system efficiency (AFUE) in practice. Let’s examine the elements comprising a complete hydronic system and their effects.

    The Indirect Water Heater (IWH) has experienced a renaissance with the availability and effectiveness of modern materials and manufacturing. Specifically Stainless Steel, Super-Insulation and Automated Manufacture provide a superb product-performance package, eclipsing its predecessors and current competition. Even so they are not “cheap” in a monetary sense, yet provide an outstanding service life while maintaining efficiency!

    Referring to our website www.BoilersOnDemand.com you will note that we integrate an IWH into our “Packaged Delta-T Hydronic FHW Heating Appliance” as standard equipment for overall performance. The HTP Superstor Ultra has been our exclusive IWH offering for over twenty years with stellar performance! There are many IWH Products available, even within HTP, but the SSU Series still exceeds.

    Referring to our “Packaged Delta-T Hydronic FHW Heating Appliance” image provided you will note four (4) basic system components:

    1. A “High-Mass” Weil-McLain Ultra Series UO Boiler.
    2. A “Green” Taco Delta-T ECM Circulator immediately above the boiler.
    3. Several Taco “Zone Sentry” Valves near circulator (for IWH) and @ top, center for heating zones.
    4. A HTP “Superstor” IWH, close-coupled to the right.

    As a standard feature on all systems utilizing an IWH as pictured, we provide a SPST (ON/OFF) Switch mounted on and in series with the IHW Aquastat. This allows selective engagement during system set-up, quick start-up, operation and diagnostics. It is visibly evident between the boiler and the IWH, placed for convenience.

    Our “System User’s Guide” refers to the IWH Selector Switch as a means of customer-inhibited operation with a two-fold purpose:

    1. Cycling only preparatory to demand DHW usage such as a dishwasher or shower(s), then “tailing” hot water via additional tasks to efficiently utilize remaining storage.
    2. Turn off DHW during protracted absences such as vacations, etc. while preserving primary area heating without risk or penalty.

    In either sequence boiler temperature is significantly reduced, ultimately approaching area ambient, reducing fuel consumption in the process.

    Using our SPST (ON/OFF) Switch as a junction box we also offer to our clients extension via another switch in series to a more convenient operating location. This is particularly helpful when considering site physicals and customer physical impairments or limitations.

    Carrying this to the next logical level is using at minimum a 1-Day or preferably a 7-Day Programmer, as may be applicable to your lifestyle. Keep in mind though that an IWH Zone uses a “dry” switch, i.e. no power applied, or you will “fry” something (your system aquastat!). Program your IWH Service to compliment your usage pattern for energy savings.

    Then you can proceed into the “wireless”, intelligent world via Wi-Fi Thermostats, Home Automation and the like. Like our “techie” customer on a work assignment in Hawaii who called us to advise he had a heating problem in his seasonal home up here in New Hampshire, the world is changing and beneficial technology is available to us all.

    By becoming “smart”, we can save ourselves a bit of trouble and a little money in the process.

    Author’s Note: Updated 01/10/2018


  • DELTA-T ECM HYDRONIC DISTRIBUTION – Really “Raising The Bar”!

    Heating and moving water (hydronics) is recognized as the most efficient method of creating and distributing warming energy. From the Roman Baths to Gravity Piped Hot Water Systems of a century ago natural convection of heated water provided a simple, if seemingly temperamental solution.

    Adding pumps (circulators) to heating water distribution has forever improved comfort an flexibility. However, their application has been less than ideal, utilizing only fixed-speed/capacity circulators, typically poorly applied to residential heating in particular. Using a “one size fits all” approach and swapping sizes to effect results has been a thorn to the trade suppliers.

    Applying switchable, multi-speed circulators has provided an interim solution to poor matching options. Further, measuring actual circulator zone supply and return temperature differentials with an infrared thermometer while selecting speed(s) has provided a more efficient solution. It’s still a less-than-ideal result, with a cost premium.

    The Delta-T (Differential Temperature Sensing) Variable Speed Circulator has been around for some years now, providing the idealized solution to heating distribution flow management. It has arguably fallen far short of its potential, burdened by high initial cost, audible operational “whine” and low speed “growling”. Occasional high load torque stalls further contributed to its unknown nature.

    Enter the ECM (Electronically Commutated Motor), the latest iteration of the “intelligent” Delta-T Variable Speed Circulator. The “heir apparent” is whisper quiet yet powerful, dramatically reduces power consumption with no “torque stalls”, displays great functional data and at a palatable cost. Taco® Comfort Solutions of Cranston, RI also claims up to 15% fuel savings along with an 85% energy drop with their 00e Series VT2218 ECM Circulator, pictured.

    Author’s Note: We former High-Tech Process Engineers were applying “Stepper Motors”, the ECM predecessors to Machine & Process Control over 40 years ago. Finally, the Heating World is getting some real tools to work with!

    The Delta-T Circulator is and has always been marketed as an enhanced replacement for a fixed or multi-speed circulator. Have a zone performance issue? Substitute a Delta-T and “tweak” it in. Problem fixed, within the constraints of the zone design and a 3X cost premium of course. This latest (and supplier exclusive) Taco® VT2218 is being very well received, breaking the “Cost-Performance Stigma” of its predecessors and counterparts. We love it!

    VT2218+ZV ultra-oil-1 HTPSuperstor

    As “High-Tech” Process and Manufacturing Engineers with a Heating Discipline we (Mercier Engineering) have further projected the Taco® Delta-T ECM VT2218 as a Dedicated System Circulator, the acknowledged INDUSTRY FIRST to do so! Reviewing its Technical Specifications the VT2218 is ideally suited to residential/light-commercial heating system applications, given that operational attributes can be accommodated. These are namely:

    1. Providing uniform heating performance under normal multi-zone demands.
    2. Simultaneously servicing an Indirect Water Heater (IWH) to optimize both domestic hot water (DWH) and heating water generation.
    3. Prioritizing DHW generation within varying area heating demands.
    4. Accommodating differential temperature branching such as radiant zone(s).
    5. Satisfying both current and future (planned expansion) demands without an efficiency penalty.
    6. Providing beneficial System Service & Reliability projections.

    Over the past fifty (50) years we have installed and monitored “conventional” hydronic (FHW) heating systems, focusing on component selections, their performance and service levels. This continual qualification process has yielded a set of Premium American Components with “zero-fail” histories, at the expense of other NAFTA, Euro & Chinese products.

    Recognizing the potential of Delta-T Hydronics Distribution as previously noted, about five (5) years ago began a concerted effort to select and qualify the dedicated system circulator application. Our independent work using three (3) successive iterations of Taco® VDT, HEC and VT/00e Products has yielded not only a viable, but a superlative Packaged Delta-T ECM Hydronic Heating Appliance™. Its performance is principally based on our Proprietary Near-Boiler Piping System that constitutes the basis of our Non-Provisional Intellectual Property Protection Submission (Patents Pending – USA & Canada).

    So what began as an “evolutionary” effort to apply a newly available “tool” in the resultant has approached a “revolutionary” one. Our Packaged Delta-T ECM Hydronic Heating System™ is actually a FHW Heating Appliance, an industry first! Placing the Delta-T ECM Circulator into a full hydronic (FHW) heating system we slogan as“Putting an ‘Automatic Transmission’ on a Boiler”. Coupling “intelligent” Taco Zone Sentry®valving (pictured), a “high-mass” boiler (Weil-McLain UOpictured)and an integrated IWH (HTP SSU45– pictured)dramatically reduce complexity and idealize hydronic system performance.

    In our introduction we referenced the “natural convection” (gravity heating) used by the Romans, et al that prefaced our “modern” hydronics. Our optimized Delta-T ECM System exhibits exceptional gravity convection qualities, continuing heating upon circulator disablement or with zone valve manual operation. Short of a full electrical outage significant gravity convection heating continues, providing a useful fail-safe protection feature.

    Now let us really “Raise The Bar”. Here is performance data taken from two (2) similar “beta test sites” in our grouping.

    100,000 BTUH System, Oil-Fired, 3-Heating Zones + IWH

    Attribute “Conventional” System Delta-T Hydronic System Comments
    System Efficiency (Est.) 87% (Boiler Only) 90++% (Aggregate) Combined Hydronic Efficiencies
    Mean Operating Temperature > 145°F (Est.) 132-140°F (Observed) Normal Heating Operation
    Distribution Power 165 Watts (Est.) 11-12 Watts (Observed) Equates to Taco® Claims
    Distribution Fuel Efficiency  N/A – 15% Consumption Per Taco® Claims
    Natural Convection  Minimal to Moderate Very Significant (Observed) Very Installation Dependent
    System Footprint < 35 Sq. Ft. 12 Sq. Ft. (Actual) Very Installation Dependent
    Construction/Life Low-Mass C.I. or Stl. + Copper High-Mass C.I. & Stl. Only  10 to 20 vs. 30+ Yrs. (Est.)
    Complexity/Maintenance/Skill Higher/Annual/Specialized Low/Bi-Annual/Standard Standard Controls Only
    System Installed Cost (Est.) $10,000+ (Est.) $7,500 (Quoted) Southern NH Region

    This is the new “Bar Height”.

    We challenge ANY Tradesman or System Installer to raise it.

    To Summarize:

    1. Delta-T ECM Hydronic Distribution is singly the most significant and cost-effective contemporary heating advancement.
    2. This technology is applicable to any fueled hydronic heating system with substantial packaging and cost benefits.
    3. System configuration using a Dedicated Delta-T ECM Circulator further reduces physical and technical complexity while idealizing hydronic performance.
    4. Our Packaged Delta-T ECM Hydronic Heating System™ is the first, true Hydronic Heating Appliance, considering its intrinsic architecture, performance and as-installed economics.
    5. This is the new Standard of Measure in Hydronic Heating.

    Author’s Note: Updated 06/12/2017


  • THE “DELTA-T” FHW HEATING ADVANTAGE

    Whether you’re replacing an existing boiler or installing a new Forced Hot Water (FHW) Heating System, the procedure is the same. A plumbing/heating guy moves in with a service truck full of parts and tools, a supply house truck arrives and drops the boiler and sundry parts. Then the game begins …..

    The old boiler (where applicable) is removed by whatever means required, the ensuing mess is cleaned up, and the new boiler is moved into the area. Locating and positioning the boiler is the first task and directly determines the effectiveness of the entire installation. The preferences, methods, materials and the heuristic judgement of the installer prevails. Thenceforth the building of the “Erector Set” continues, pipe by pipe, wire by wire, device by device until the task is finally completed. It’s a slow, costly and inefficient process …..

    All tradesmen develop their own methodologies, reflecting their pride and workmanship in the resultant. Unfortunately the customer pays a premium for this both initially and throughout the lifetime of his system ….. knowingly or not! We cynically refer to boiler installations as “The Plumber’s Playground”, that last vestige of “free expression” removing us from the daily tedium of “fixing leaks and squeaks”.

    Installing or replacing a boiler should be no different than a dishwasher or a water softener, with a few more pipes and wires attached ….. and it can be! Problem is we plumbing/heating guys (ourselves included) continually lag technology. We “Old Dogs have to learn New Tricks”, and brother we have!

    Recent technology now allows us to configure a FHW (Hydronic) Heating System as a true appliance! All heating system functions excepting radiation can now be integrated into a “packaged unit”, engineering it for peak performance and value in the process. “Delta-T” (Differential Temperature) Circulation Technology is truly an evolutionary and revolutionary improvement. Developed in the “high-tech” process world, it has now become both practical and economical as applied to Residential Hydronics (FHW Heating).

    Mercier Engineering via its website www.BoilersOnDemand.com is the introductory leader of Residential Delta-T Hydronic Heating. The question is not if Delta-T Circulation will out-distance conventional Fixed-Speed Circulation, but when. Evidence the following Pictorials and Details for comparison.

    Identically Configured Oil-Fired FHW Installations          

    Conventional Oil-Fired FHW System   “Delta-T” Oil-Fired FHW System
    Typical Plumber Boiler Install - 18 hrs DTO-100T2(Exp)H4-4X6

    Features Comparison Table

    Attribute"Conventional" System"Delta-T" SystemComments
    Boiler TypeWelded Steel Plate (Example Unit)Cast Iron "Triple-Pass"15 years +/- vs. 30 Years +
    Boiler Weight270 Lbs.625 Lbs.Very High Mass - Durability
    Oil Burner TypeVarious OfferedBeckett NX (Pressure-Fired)Flexible, stable operation
    Gas Burner TypeFixed, Appliance-SpecificCarlin EZ-PRO (NG/LP) (Pressure-Fired)Appliance-Specific Interchange
    CirculationMultiple Fixed Speed Circulators onlyA Delta-T Variable Circulator w/ Intelligent Zone Valves>/ 15% Fuel Savings
    >/ 85% Electrical Savings
    Piping/FittingsCopper (Typically)All Iron & Cast ConstructionSuperior Strength/Durability
    Indirect Water HeaterVarious Mfrs. & TypesAll Stainless Steel OnlyA Lifetime of Service
    Floor Space UtilizationInstaller-dependentOptimized Package DesignMinimum Space Requirement
    Energy PerformanceInstaller-dependentOptimized Energy DesignPeaked Hydronic Efficiency
    Component SourcesU.S./Foreign Mix (Typical)"All-American" (US/Canada)Quality and Serviceability
    Installed Cost (Oil example shown)"Over $10,000" (Oil, as shown)$7,000 (Oil, as shown)Price, Performance, Value

    Notes:

    1. Estimated service lives are from our and our collaborating serviceman’s actual field experience.
    2. Fuel & Electrical Energy Performance per Taco, Inc. published testing data.

    Reviewing our Comparative System Photos will will confirm many of the suppositions in our “Features Comparison Table” above. The immediate impression is one of excessive plumbing and space consumption of the Conventional System. In fact the “Delta-T” System occupies 1/3 of the space, uses 1/2 of the near-boiler piping (with no copper), with only one (1) Circulator, fewer valves and fittings ….. and with optimized hydronic flow and distribution performance! Flow is so idealized in fact that under certain component fail modes “gravity induced circulation” will continue to provide heating at a reduced level! (Patent Pending)

    Arguably a high-mass (heavy) “Delta-T” System will outlast two (2) Conventional FHW Systems with a higher Hydronic Total System Efficiency at 1/3 the “life-cycle” cost.

    So when your potential FHW Heating System Installer comes calling, ask him first about “Delta-T” Circulation. If it draws a blank stare, send him home to call Taco, Inc. — and that another “Old Dog” told you to do so. After all, you the customers are deserving of all the “New Tricks”!