Superior Heatform Model D Help

[anh140]

We just moved into a new (to us- built in 1978) house. Had chimney inspected and sweep recommended re-lining chimney. Had that done and had our first two fires this week. It’s a double sided Superior Heatform model D (I just discovered today while researching my issue). There are tempered glass doors on both sides of the fireplace, and we have discovered that when they open, smoke billows out of the fireplace and into the room, almost like it’s being drawn into the warm air return (but I don’t think it actually is). I believe we should be able to have a fire going without the doors based on the old manual/sales materials I found - but curious if anyone has any idea what may be causing this? Or any way to fix it? Could the re-lining of the chimney have affected the draft? Could they have installed it wrong and put the doors on to mitigate the issue? Apparently the forms are still in place and concreted in - could that be part of the issue? Our chimney sweep was going to remove them but was unable to.

I’m going to try to find a chimney sweep who knows more about these but in the mean time , any ideas appreciated!! (This fireplace is a big reason of why I wanted this house and if it’s not usable (and we just spent a ton of money repairing some thing the wrong way) I’m going to be sad sad sad! Ha))

 

[begreen]

When the chimney was relined, what was the process? Did they put in a stainless liner, or a cast in place liner?

 

[anh140]

When the chimney was relined, what was the process? Did they put in a stainless liner, or a cast in place liner?

The quote from him says: “apply fire guard prue ceramic sealant to seal and repair all mortar joints in lining system” (so I maybe misunderstood the process, but I believe this is what we had done)

 

[begreen]

It's possible that the flue is undersized for the fireplace, or it could be in a poor location relative to the house's roofline, or it could be too short.

EDIT: Rereading the original post I see that the fireplace was described as "double-sided". If it has two opening (one per room) then that may be important. Double-sided fireplaces need a bigger flue due to the extra air introduced. Are there doors on either side?

 

[anh140]

Yes. There are doors on both sides. The chimney opening and damper are definitely larger than the fireplace in our former home. I was wondering about the location based on some things I found in the old brochure because we do live down a hill… but I hope/assume they wouldn’t have placed it incorrectly when they built the house? But I guess anything’s possible? Or is it possible that the growth of trees along the property line/yard up hill could be affecting the draft?

 

[anh140]

Also i guess im wondering if the issue is because of the heat form or id potentially have the same issue with any chimney?

 

[begreen]

Yes. There are doors on both sides. The chimney opening and damper are definitely larger than the fireplace in our former home. I was wondering about the location based on some things I found in the old brochure because we do live down a hill… but I hope/assume they wouldn’t have placed it incorrectly when they built the house? But I guess anything’s possible? Or is it possible that the growth of trees along the property line/yard up hill could be affecting the draft?

Fireplaces and chimneys are often mislocated at the behest of the owner or poorly informed architect placing visual form before function.

Closing the door on one side should help, but if it a sluggish flue due to other issues then it may take warming up the chimney before the smoke rollout stops. If the chimney is really poorly located then there are fewer solutions.
This site has several good articles on chimneys

A non-commercial service in support of responsible home heating with wood - How Wind Affects Chimney Performance

The Wood Heat Organization was formed to support the public in the responsible use of wood energy in the home. We fulfill our mandate by providing reliable information, by conducting research into wood heating-related issues and by representing the public interest in discussions of policies that...

woodheat.org

 

[anh140]

Thanks for the article. We did try opening one set of doors and not the other to no difference. We’re going to have our chimney sweep come out and look again. Do you think the fact that it’s a Heatform could have any impact on the issues we’re experiencing or that shouldn’t make a difference?

 

[begreen]

The heatform probably is not the problem unless it has started to rot out at the top. It's good to have a set of trained eyes to investigate for any issues like this. Is there a damper in this unit? Can you look up the flue and see daylight above?