closing off air intake for blower door test

[twd000]

I have a home energy audit scheduled in a couple weeks

One of the diagnostic tests is a blower door test, where they depressurize the house to measure air leakage. They sent the typical prep instructions including:
1. let the fire burn out cold for 24 hours prior to the audit
2. vacuum out all the ashes so they don't get sucked into the house
3. close the flue

I'm fine with #1 & 2, but how do I close the flue on my BK Princess insert? Even when I dial the thermostat down to the lowest setting, isn't the air intake damper still slightly open?

 

[MyAppleJacks]

Congrats on your energy audit. Smart step towards a more efficient home. I wouldn't be to concerned with this one. Your insert shouldn't be a problem with the audit. It's more than likely one of the more air tight items in your home. I believe your door and gasket would act as "closing the flue" for the audit. You could leave your damper wide open if you wanted to as long as your door is closed.

Goodluck and let us know how the audit goes.

 

[bholler]

I have a home energy audit scheduled in a couple weeks

One of the diagnostic tests is a blower door test, where they depressurize the house to measure air leakage. They sent the typical prep instructions including:
1. let the fire burn out cold for 24 hours prior to the audit
2. vacuum out all the ashes so they don't get sucked into the house
3. close the flue

I'm fine with #1 & 2, but how do I close the flue on my BK Princess insert? Even when I dial the thermostat down to the lowest setting, isn't the air intake damper still slightly open?

Yes it is you could always stuff a plug into the flue through the bypass. Because the intake flap will offer no resistance to the vacume at all.

 

[moresnow]

Go up on the roof and plastic bag it! Maybe? Or cover the entire stove/surround front with taped on plastic? These tests are sensitive. Interesting question! Good luck. Let us know the result.

 

[bholler]

Plastic over the top of the liner is probably the best solution

 

[MyAppleJacks]

In theory you could plastic cover the air intake outside or over the entire insert. It never crossed my mind to manipulate false results of an audit (Must be my profession.). If this were me, I would close the door and shut the dampers down to get the most accurate results from the audit. It may uncover an issue that could result in simple remediation.

 

[bholler]

In theory you could plastic cover the air intake outside or over the entire insert. It never crossed my mind to manipulate false results of an audit (Must be my profession.). If this were me, I would close the door and shut the dampers down to get the most accurate results from the audit. It may uncover an issue that could result in simple remediation.

This is not falsifying anything. I would only cover the liner that way you can find out if you have leaks around the insert. But on a blazeking where the air is controlled by a flap when the stove is operating it is under vacume pulling that flap closed. But with the house under vacume the flap will be pulled wide open allowing free flow of air where there normally wouldn't be.

 

[twd000]

Go up on the roof and plastic bag it! Maybe? Or cover the entire stove/surround front with taped on plastic? These tests are sensitive. Interesting question! Good luck. Let us know the result.

it's single-digit cold and I have a thin layer of ice on top of an inch of snow on my roof. I'm not getting out the extension ladder and climbing around up there to seal off the top of the liner

 

[bholler]

it's single-digit cold and I have a thin layer of ice on top of an inch of snow on my roof. I'm not getting out the extension ladder and climbing around up there to seal off the top of the liner

Ok so stuff something up into the flue through the bypass damper.

 

[twd000]

Congrats on your energy audit. Smart step towards a more efficient home. I wouldn't be to concerned with this one. Your insert shouldn't be a problem with the audit. It's more than likely one of the more air tight items in your home. I believe your door and gasket would act as "closing the flue" for the audit. You could leave your damper wide open if you wanted to as long as your door is closed.

Goodluck and let us know how the audit goes.

thanks I'm intrigued to see what they find, and to some remediation. Our mid-70's Colonial has been "good enough" if a bit drafty until this year, when my 18-month old daughter moved out of our room and into her room down the hall which is frigid with the door closed. It is the longest distance from the main HVAC branch and I suspect there is some serious leakage coming flowing out of the duct work and into the unconditioned attic.

 

[MyAppleJacks]

The best recommendation would be to contact the energy audit company and disclose to them that you have an air intake to a wood burning insert and if they could provide any insight if closing your damper, as is, would be low-impacting. The auditor may have equipment if it's a significant issue and could save you a trip outside in the cold.

 

[twd000]

Ok so stuff something up into the flue through the bypass damper.

I guess that's what I'll do. Any wagers on how long it will take me to realize I left the plug in place after the first re-fire?

Now I'm thinking more about the goals of the test, and what I really want to measure. I'm sure there is some airflow between the block-off plate and the chimney, and between the plate and liner, because it's not a perfect seal. But I'm not sure what I would do about it.

Also when I'm not using the stove, there is probably a constant (small) draft through the air intake and up the liner, that would be another source of energy loss. Should I plug up the liner in the spring too?

 

[bholler]

I guess that's what I'll do. Any wagers on how long it will take me to realize I left the plug in place after the first re-fire?

Now I'm thinking more about the goals of the test, and what I really want to measure. I'm sure there is some airflow between the block-off plate and the chimney, and between the plate and liner, because it's not a perfect seal. But I'm not sure what I would do about it.

Also when I'm not using the stove, there is probably a constant (small) draft through the air intake and up the liner, that would be another source of energy loss. Should I plug up the liner in the spring too?

Put a peice of tape on the door and write remove plug on it when you do it.

 

[maple1]

IMO I would only close down the insert fully as I could using whatever insert & flue controls you have. They might just mean 'close the flue damper'.

If the chimney needs 'closed' or plugged - that should be on them to do.

My thoughts - never been through one of these.

 

[MyAppleJacks]

I've found this thread to assist in making your decision:

https://www.hearth.com/talk/threads/home-energy-audit-blower-door-test.121666/

Let us know how it goes.

 

[yooper08]

Now I'm thinking more about the goals of the test, and what I really want to measure. I'm sure there is some airflow between the block-off plate and the chimney, and between the plate and liner, because it's not a perfect seal. But I'm not sure what I would do about it.

Also when I'm not using the stove, there is probably a constant (small) draft through the air intake and up the liner, that would be another source of energy loss. Should I plug up the liner in the spring too?

As bholler said, just plug the flue. That should get you close to sealing it off. The auditor should also verify that the stove's air controls are shut.

The point of the blower door test, besides measuring air leakage, is to make it easier to find drafty areas with a thermal camera. The auditor will probably skip the area around the stove at this point, or to your point, may suggest plugging the flue in the spring in the name of efficiency.

As for air leakage into the attic via HVAC ducts, I cover mine up each winter due to that. If I don't, cold air comes rushing down. That may be what's happening to you. So, if you don't use the ducts for heating in winter, that's a potential solution. From an energy auditor's perspective (and mine), ducts in the attic like that is a stupid idea. That said, when I had my audit done a few years ago, they wanted to spray foam the duct work in my attic to insulate and seal them.

 

[MyAppleJacks]

I would agree at this point if it's for personal use to know other potential leaks in the house plug it. You did not disclose if this is a contingency of sale. I would recommend leaving it as is to avoid manipulating any false reports unless you are disclosing it is plugged.

Advice from an auditor.

 

[planner steve]

I have a home energy audit scheduled in a couple weeks

One of the diagnostic tests is a blower door test, where they depressurize the house to measure air leakage. They sent the typical prep instructions including:
1. let the fire burn out cold for 24 hours prior to the audit
2. vacuum out all the ashes so they don't get sucked into the house
3. close the flue

I'm fine with #1 & 2, but how do I close the flue on my BK Princess insert? Even when I dial the thermostat down to the lowest setting, isn't the air intake damper still slightly open?

When I had my blower door test done, I put a plug in the outside air intake line. My PE Super 27 installation has no flue damper. My energy auditor said this was acceptable way to do it. During the test I felt around the stove and could not feel cold air being pulled in anywhere.

 

[twd000]

I would agree at this point if it's for personal use to know other potential leaks in the house plug it. You did not disclose if this is a contingency of sale. I would recommend leaving it as is to avoid manipulating any false reports unless you are disclosing it is plugged.

Advice from an auditor.

Not a sales contingency- just something for our own comfort and fuel savings

 

[ShawnLiNY]

I would agree at this point if it's for personal use to know other potential leaks in the house plug it. You did not disclose if this is a contingency of sale. I would recommend leaving it as is to avoid manipulating any false reports unless you are disclosing it is plugged.

Advice from an auditor.

That’s preposterous Dude ! It’s not an engineering report ,or asbestos abatement certificate.potoble water tests , Radon etc . Read his post it’s for an energy audit .