Questions on an HB36A, popping noise from flue?

  • Active since 1995, Hearth.com is THE place on the internet for free information and advice about wood stoves, pellet stoves and other energy saving equipment.

    We strive to provide opinions, articles, discussions and history related to Hearth Products and in a more general sense, energy issues.

    We promote the EFFICIENT, RESPONSIBLE, CLEAN and SAFE use of all fuels, whether renewable or fossil.

castironfanatic

New Member
Oct 10, 2022
2
Omaha, Nebraska
Hi all,

I recently purchased a new home in the Omaha area and in the process acquired a fireplace. We've used it a handful of times and really enjoy it. I have a couple questions/concerns with it. I had a chimney sweep come out to do an inspection and cleaning before we started it up. They said it looks great good to use and asked me if I had any questions, but I didn't have any at the time. I'm thinking about calling them back up but figured I would drop my questions here first to see what all of you thought. The fireplace we have is, I believe a Heatilator HB36A, manufacture date of '88.

I noticed when I turned on my central heat that I hear a popping noise initially when the heat turns on for a good 5 minutes or so. The popping noise starts out fast and slows down until it stops entirely. At first I thought it was an issue with the ducting in my home, but after further inspection I now believe it is actually the flue of my fireplace. I think I am losing air out of my fireplace and the flue is expanding as hot air escapes. I made sure the damper was fully closed and doors shut. The bi fold doors of course don't have a tight seal at all and the damper doesn't seem air tight by any means. From what I read it isn't realistic to replace the doors with something that seals better, replacements will all be equally as leaky. Is this true? Am I better off to replace the damper with something that has a better seal, is this the way to go? Is there another way to resolve this that I should be looking into?

My other question is regarding the outside combustion air kit. I read the manual and see an outside air kit referenced (CAK4) but don't see any explanation of how to control it. There is a little lever in the lower right side of my fireplace. I believe this is to control the air flow. I can't find in the manual how to tell if it is open or closed! Push in or out? I think it might be stuck open no matter what I do.

I'm thinking about replacing it with a more efficient epa certified unit in the future, but want to get some life out of this one as I save up. Your help is appreciated!

Thank you,

Justin
 
Hey Justin,

Yeah sorry man, it looks like you've found everything you can on it. I took a peek as well, and I found install instructions for the CAK4, but that's about it. Have you tried getting in touch with Heatilator at all? It looks like they're still up and running, so I wonder if a quick message off to them would yield any helpful results?
 
Thanks for the message RomanW. I tried to reach out to Heatilator but they direct the request to the closest Heatilator dealer in the area. They just recommended using an inflatable fireplace plug, which I could do during the longer periods that I am not using it. They said there would not be a tighter sealing replacement damper. However the chimney sweep did say there was a type that can be installed toward the top of the flue and then a pull chain is installed inside the fireplace. I might have them handle that the next time they are out. I also got some of those magnetic vent covers to try, they stay up alright. I think if I get them trimmed just right I can get it to work better and maybe tape a handle onto it or something so I can reach in and pull it off easier.
I've gotten absolutely no answers on the combustion air kit. I ran it the last couple of times with the lever pulled all the way out. I am going to try it with the lever pushed all the way in next time and see if it acts any differently. Other than that all I can think to do is pull the vent off the outside of the chimney and see what I can see as far as the mechanism that controls the air kit.
 
  • Like
Reactions: RomanW
That sucks man, I'm sorry to hear that. Sounds like you've got some headway on some other stuff though! Will be interesting to see how it turns out!