“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.
- 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.
- 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.