Cold Air When Off

[brogsie]

My sister has a gas fireplace that is very cold when off. Is there a flapper to prevent back draft?
It's installed in a wood bump out and vents horizontally and two feet above the unit. My other thought was maybe they didn't insulate behind the fireplace unit?

 

[DAKSY]

You can try to seal all the holes in the bottom of the unit, where the gas valve is, with aluminum tape. That should help a bit. The problem is that bump out or doghouse. There's NO HEAT in it. Even if the builder installed it correctly & insulated the walls behind, the floor below & the fire deck above it, the only heat in there is when the gas is burning. When the fire is out, the box gets COLD. Warm air will enter the top of the unit, get chilled by the COLD metal, drop down thru the back & exit the bottom. It feels like a draft from the outside but it's really reversed air convection. If she has an option to keep the pilot burning, that can also help a bit. Try taping EVERY wall penetration in the valve cavity, no matter how small...

 

[brogsie]

Thanks, DASKY

 

[DAKSY]

Uhh..DAKSY. You're welcome, tho...

 

[brogsie]

Took the glass off the fireplace. Cold air was pouring down the flue vent. Is there any way to put a damper on the exit pipe?
I know because it's gas there are regulations for safety reasons but the cold is unbelievable. There is a full basement under so no cold underneath.

 

[DAKSY]

No Damper. Either keep the pilot burning (if you can) to mitigate the chill or keep the burner on.
If she doesn't want to use it at all, turn the gas to the unit off & duct tape some plastic to the front & seal it.

 

[brogsie]

Thanks again DAKSY. It has electronic ignition so the cold is just pouring in. I can't believe they would manufacture something that needed to be duct taped to keep cold out when off. She has one in another room that seems fine. That one exits twelve or so feet above the unit. The cold one only goes up only two feet then out the wall.

 

[DAKSY]

Some electronic ignition (IPI) units will allow you to have a constant pilot during cold weather, just for this problem that you are referring to. What brand & model are we talking about, anyway?

 

[brogsie]

It's a Heatilator. Not sure what model. I will have to see if the former owner left a manual.

 

[DAKSY]

Take a look in the valve cavity - under the firebox. On the right side floor there should be a sticker with the model & serial number.

 

[brogsie]

Will check next time I'm at her house. Thanks DAKSY

 

[bbone]

brogsie, mine does the same thing, (also built in a doghouse) seems to just be what it is (nothing wrong with it)
if I run it for a hour or 2 the cold stays away for many hours
I have just resorted to putting a blanket in front when not in use, stops draft