Could a heat pump unit be used to heat a crawl space that is closed in?
Bombo| Posted inGeneral Questionson
I’m thinking about having a heat pump system added to my mobile home. The home is about 1500 sq. ft., with a crawl space about 3 1/2 ft from slab to bottom of the mobile home.
This would help heat the floor above and allow me from leaving my home unoccupied for a time during the winter and only have the heaters keep temps around 56.
Well above 35 degrees.
Could this be done?
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Replies
Leonard,
Usually, mobile homes with crawl spaces have sloppily made skirts (crawl space walls) that leak air and have a low R-value. If you have that type of skirt, your first order of business is to perform air sealing work on the skirt, and to add another layer of rigid foam to the skirt (protected from abuse or sunlight, of course, with a layer of OSB or pressure-treated plywood).
If your pipes are freezing, the usual remedy is to install electrical heat tape and pipe insulation on the vulnerable pipes. This will be cheaper to operate than trying to keep the crawl space warm.
All that said, there is no reason you couldn't install a ductless minsiplit in your crawl space. It's an expensive installation, however, and I don't recommend it.
Spending the mini-split money on insulated air tight skirting to "earth couple" the mobile home to the thermal mass of the subsoil is enough to prevent plumbing from freezing in more temperate locations. Where is the house located?
There have been some big disasters involving "unoccupied", "winter" and frozen pipes. So consider setting up an air compressor and valves such that it is very easy to empty the pipes. Safer and less energy.