HVAC Plumbing

Can anyone tell me why these lines have this section installed in it.

These are the Fresh air and exhaust lines to the furnace.

To muffle the sound of most lennox pulse furnaces.


So no problem with the installation then??

Thanks guys.


If thats the venting for a Lennox G14 or GSR14 series pulse furnace, there have been a history of problems with cracked heat exchangers. Those need evaluation by a specialist.



I was unable to verify the date aside from a sharpie marking dating for March of 1983.
Due to a low output of heat from the registers. A temp diff of 6 degrees on both heat and cool cycles, and an unknown last service date.

I recommended a full system evaluation by a licensed HVAC tech before further pursuit of purchase.

You can get a 6° temperature difference just because the duct passes through the attic or crawlspace.

I don’t think anything was working.

Please inform your client as these can be a very real safety hazard.

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