Hi, I had a gas Calcana radiant tube garage heater installed by a professional gasfitter.
The model is Calcanas CAL-40A M and is natural gas.
It is draws air from the outside and vents to the other side of the garage. It has a blower in it so air is forced through the system.
I had a City of Calgary inspector over to have the permit signed off, and he has said the exhaust venting is unacceptable. The vent was piped to have 2 elbows to allow it to ‘Z’ down to clear part of the ceiling before it goes outside beneath the soffit.
The inspector doesn’t like the 20" of straight pipe between the 2 elbows. He has referenced the installation manual which only shows 2 elbows butted up to each other and says you can’t have the extension between the elbows. I’ve talked to the manufacturer over the phone and the guy I talked to said yes there’s no issue with the straight section between the elbows, but that they’ve had issues in the past where the inspector won’t approve the install because the manual does not show it with the straight section.
Now, I’m a mechanical engineer, and I’m not saying I know what should be acceptable because I don’t deal with HVAC or gas systems, but from my technical perspective I can’t see a physical issue or concern with the straight section, especially because it goes down and out, and not up and out. The added straight section would have similar effect as adding an extra 20" of lateral pipe to the vent, which would be fine. The vent system would have less head pressure at the output that if you had 2 elbows butted up and going straight out, so I agree with the manufacturer that it should be approved.
So, I’m not sure what to do now. I guess I can re-route the vent, or drop the heater down, but it would be an eyesore and there’s a man door going into the house that would almost be blocked by the vent line, so it’s not ideal…
Has anyone had similar issues or can someone suggest what I should do? My thoughts were to try to have the manufacturer, Calcana, talk directly with the City. Or is there something in CSA B149 that would explain why this installation is okay?
I will try to upload some pictures and the manual, it looks like I can’t directly attach files here.