Keeping a jet-pump from freezing?
lumbermonkey
| Posted in Energy, Heating & Insulation on
Hey Guys, I have a jet-pump and pressure tank in the crawl space under our cabin. With the winter moving in I’m wondering how to keep it from freezing. The one I took out was busted by the ice. It’s half in the ground and boxed in with plywood. I was thinking about wrapping it in heat tape, lining the box with foam and maybe packing the rest of the space with insulation.
Too much? Not enough?
Replies
Where do you live? How cold does it get? How deep is the local frost line?
Keep in mind that the earth is generally warm, and generally stays above freezing in the southern half of the US. So the main thing you want to do is to capture the heat from the earth somehow.
Oh, and BTW, how tall is the crawl space?
I think the insulated box is a good idea.
I'd make it plenty big, so that air can circulate inside, and line it with 2" SM. Throw some heat tape inside and make sure the thermostat is INSIDE the box.
Scott.
Do you use the cabin in the heating season? I assume so. Is the crawl enclosed or completely open? If open, create a 'room' at that location connected to the floor and ground. Insulate that 'room'. Do a really good job. Your profile doesn't say where you are located. You might want to make the room somewhat larger than the frost depth. For example if the frost depth is say 30", you'd make the 'room' 60" on a side (30" in each direction). Remember heat flows in all directions, so a connection to the heated space (the floor) will help minimize freezing conditions. Oh, make sure the floor is NOT insulated at the 'room'.
While you may have a tendency to not use much craftsmanship in such a situation, it will be some good craftsmanship (although maybe not pretty) that will make or break your success. The room needs to be 'tight' ... and you may need to make it accessible to service the equipment.
If it is an enclosed crawl, seriously consider operable crawl vents to be closed in the heating season.
Thanks for the advice. It's a contained crawl space and the previous owner left foam panels to block the vents. I will heat the space to around 50 all season long. It's in SW Wisconsin and the living space is well insulated and small, 600 sqft.
I'm guessing I leave the floor of the pump space uninsulated so the geothermal can rise?
In SW Wisconsin you're going to need some real live heat in there to prevent freezing. Or completely drain the setup in the winter (and maybe flush it with RV antifreeze to be sure).
As I stood before the gates I realized that I never want to be as certain about anything as were the people who built this place. --Rabbi Sheila Peltz, on her visit to Auschwitz
If you can close off the crawl in the winter, that's going to be the easiest (theoretically;) ). Make sure you pay attention to details to ensure the crawl walls will minimize air leakage. Yes, never insulate under something like that. The earth is your friend ... go ahead hug it. ;) An insulated crawl perimeter is ideal for the house in general if you have the means and use the house a lot in the winter.