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Heat pump compressor in unconditioned /isolated / vented basement?

Could this work in cold climate 5? Bsmt floor Sealed and thermally broken from upstairs units. Would a Vented basement make that possible?

Asked by matt berges
Posted Jan 30, 2013 12:38 AM ET


5 Answers

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The short answer is no.

The long answer depends on several factors. The most important question: what is the purpose of the heat pump? Will it be used to provide space heat for the home above? (If so, your plan won't work).

If the heat pump compressor is used to provide domestic hot water, the plan might work.

Here's what happens when you put a heat-pump compressor in a basement: the heat pump makes the space colder and colder. You'll find that it's hard to get much outdoor air to flow through the basement. Eventually the basement will freeze. If you have any plumbing pipes in the basement, the plumbing pipes will freeze.

Answered by Martin Holladay
Posted Jan 30, 2013 6:44 AM ET


Assuming we're talking about the outdoor unit of a split heating/cooling system, then I second Martin's short answer. These things move 1500-2000 cfm of air for 2-3 ton units. That's quite a lot of venting for a basement.

Answered by Cramer Silkworth
Posted Jan 30, 2013 6:03 PM ET
Edited Jan 30, 2013 6:04 PM ET.


Thank you both. Yes, it is the outside unit that I am talking about, and I was trying to figure out how much air flow would be needed in this isolated, unconditioned space. What I was trying to describe was an unfinished, unconditioned, isolated basement that is cut off from the rest of the building, except by outside access. I figured I would have to cross vent the basement well, but had no idea of how much would be needed. The project is in a area where I was worried about the outside units walking away. There would be no exposed plumbing in the basement (for fear that it would freeze anyway, even without the heat pump compressor). Anyway, I dont think I have any new info that would change your answers...so thanks!

Answered by matt berges
Posted Jan 30, 2013 9:13 PM ET


Air source heat pumps need access to their source- the great outdoors. Cooping them up in a basement would just kill them on efficiency, cooling the basement to below the outdoor air temp in winter.

Answered by Dana Dorsett
Posted Jan 31, 2013 7:19 PM ET


Yep, nice try but no cigar. Stealing heat from the house to heat the house: robbing Peter to pay Paul

Answered by James Morgan
Posted Feb 2, 2013 1:37 PM ET

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