Make-up air

JackFre

I replaced all the windows in my home and it was a completely different structure from heating, infiltration, standpoint.

Check out Tjernlund's Enforcer. It interlocks with the burner and runs only when you have a call for heat. Designed to provide both combustion and ventilation air.

David Hohengasser

Make-up air

How do I know if I need to supply make-up air? It is an older home circa 1920. The cellar contains 187,000 input gas steam boiler, two 40 gallon gas water heaters and two clothes dryers. There are four small windows that have storms, but are not perfectly air tight. I have never had a problem in the past, but am installing replacement windows throughout the main house. I'm sure some make up air from the old windows had been seeping through door cracks into the cellar. What kind of test can a homeowner do?

Glen

Local gas code -

will dictate sizing and placement of combustion air. In some cases - it may also require relief air. Call a licenced gas pro in your area for correct advice. Do not consider air infiltration sufficient for your fuel burning appliances.

t. tekushan

In-Forcer

> I replaced all the windows in my home and it was

> a completely different structure from heating,

> infiltration, standpoint.

>

> Check out

> Tjernlund's Enforcer. It interlocks with the

> burner and runs only when you have a call for

> heat. Designed to provide both combustion and

> ventilation air.



The In-Forcer literature is really good because it gives very specific numbers with regard to required air flow.

Whats interesting is that the primary complaint about original (and sometimes architecturally significant) windows and doors is air infiltration. Yet the concern about make-up air crops up only AFTER these things have been replaced. In actuality, the air infiltration is caused by the need for make-up air in the first place.

If a structure isn't so tight, and is difficult to make tight which may include important architectural elements such as windows and doors, I've decided to turn the problem on its head. I deal with the make up air FIRST. I've found that in the absence of high winds air infiltration is dramatically reduced.

I understand the importance of a blower door test, etc, but I prefer to put in the make up air and focus on radiant heat loss by installing or augmenting insulation, and installing storm windows and window films.

Of course, I learned all this backwards. I have pre-wwII steel casement windows that look great and such but they were leaky and cold, to say the least. So I made weather seals for them so they would seal tight as a drum. Mission accomplished. Or so I thought. Now the doors were leaking more. More weather sealing and new thresholds. Now the fireplace backdrafted. AAAAAAGH!

Then I attended some local seminars put on by the Interfaith Coalition on Energy, whose goal is the use of sensible strategies for energy conservation in sacred (and often historic) buildings like churches and synogogues. A lesson learned early is to pay less attention to where air is coming in than where its going out and why.

It all made sense. Especially in very old, loose structures. I installed make up air as if I was in a new, hermetically sealed home. All those extraneous drafts disappeared. The whole house is more comfortable. Anyone I know who has tried this approach reported similar results. Without touching anything else, comfort levels increased, heat loss decreased. The focus of energy saving strategies then moved to insulation and boiler/furnace maintenance, which are some of those things that actually has a realistic monetary pay-back period.

I hope this is helpful.

t. tekushan

In-Forcer

The In-Forcer literature is really good because it gives very specific numbers with regard to required air flow.

Whats interesting is that the primary complaint about original (and sometimes architecturally significant) windows and doors is air infiltration. Yet the concern about make-up air crops up only AFTER these things have been replaced. In actuality, the air infiltration is caused by the need for make-up air in the first place.

If a structure isn't so tight, and is difficult to make tight which may include important architectural elements such as windows and doors, I've decided to turn the problem on its head. I deal with the make up air FIRST. I've found that in the absence of high winds air infiltration is dramatically reduced.

I understand the importance of a blower door test, etc, but I prefer to put in the make up air and focus on radiant heat loss by installing or augmenting insulation, and installing storm windows and window films.

Of course, I learned all this backwards. I have pre-wwII steel casement windows that look great and such but they were leaky and cold, to say the least. So I made weather seals for them so they would seal tight as a drum. Mission accomplished. Or so I thought. Now the doors were leaking more. More weather sealing and new thresholds. Now the fireplace backdrafted. AAAAAAGH!

Then I attended some local seminars put on by the Interfaith Coalition on Energy, whose goal is the use of sensible strategies for energy conservation in sacred (and often historic) buildings like churches and synogogues. A lesson learned early is to pay less attention to where air is coming in than where its going out and why.

It all made sense. Especially in very old, loose structures. I installed make up air as if I was in a new, hermetically sealed home. All those extraneous drafts disappeared. The whole house is more comfortable. Anyone I know who has tried this approach reported similar results. Without touching anything else, comfort levels increased, heat loss decreased. The focus of energy saving strategies then moved to insulation and boiler/furnace maintenance, which are some of those things that actually has a realistic monetary pay-back period.

I hope this is helpful.

-Terry

P.S. I built interior storm windows for those steel casements. The frame is slim and holds 3/16" acrylic glazing, with a heavy felt spline around the perimeter to seal it against the interior return wall. It merely pushes firmly in place. The acrylic is not exposed to weather so it holds up great. It also has a very high insulating value due to its low density. You would need triple glass to match its performance. It also has great low emissivity properties (reflecting long-wave i.e. radiant energy back into the room) and UV blocking. All this without changing the visible light intensity or color temperature. It looks like nothing's there! I'll share the easy weather seal trick if anyone's intersted.

william graziano

I'm interested

Terry,

I have been thinking about interior storm windows. What size wood did you use for the frame. How did you do the felt sealing.

Bill

Dirk Wright

HVAC Code Check book

The HVAC Code Check book has a section on this. You determine what you need based on the total btu's burned and the sq. ft. of open space in the basement, as I recall. They have charts for determining the duct size required. Hope this helps.