QUESTION FROM Garry

I recently purchased a heat pump. I am considering building my own cover for my new heat pump. I was thinking of using 4 -4x4 PT posts and installing to the posts a plywood PT for a top cover, in the winter when it gets too cold for operation , snow, temp below 30 degrees, etc., I would close in the 4 open sides w/PT plywood for the winter. But when in operation would a permanent cover placed approx. 2 feet above the unit hinder its operation. Please advise me. I live upstate/central New York State.

ANSWER FROM POLICY-Wizard™

Dear Garry:

Regarding building a permanent cover for your new heat pump, here’s a couple of thoughts that you should consider.

First, since you live in a relatively cold climate (upstate/central New York), you are correct that there will be periods during the winter when the outside temperature will be below freezing, and as such, it will not be efficient to operate your heat pump. And yes, its wise to want to protect your heat pump from falling branches, ice, snow, leaves, etc. The other advantage to having a cover around your heat pump is that if your unit is in direct sunlight, then having a cover above it will provide shade which will help keep it cooler in the summer, and this will help it’s operation.

However, the problem with installing a permanent cover around your heat pump is that it could impede the flow of air around the unit, and therefore reduce the efficiency of your unit. Having adequate air flow around your unit is critical to it operating properly. It is this air flow that enables the unit to exchange the heat from inside your house and bring it outside during the summer months, and to extract the heat from the air outside your house and bring it inside when you need it during the winter months (that is, the winter months before the weather drops below freezing). So if your permanent cover reduces this air flow, then your heat pump can’t do its job properly.

So if you do install a permanent cover, then you will want to leave plenty of room around your heat pump to let it “breathe”. I suspect that just allowing 2 feet above the unit is probably not going to be enough space, depending on the size of your unit and how much natural air flow there is around where the unit is located.

Secondly, you mentioned that you were planning on using what sounded like a sheet of pressure-treated plywood as the top cover. If this is the case, then you should consider pitching this cover like a tent or roof. Because if it is left flat, then the weight of the snow and ice could become heavy enough to cause it all to come crashing down on your new heat pump.

Lastly, rather than installing a permanent structure around your heat pump, you might want to consider covering it with a tarp in the coldest months of the winter, and removing the tarp when the weather warms up. This is described in the Home-Wizard Maintenance Library for air conditioners (see Task #4): http://www.home-wizard.com/maintenance/airconditioning.asp You can even add a piece of plywood to go underneath the tarp, for extra protection.

Hope this is helpful.
Home-Wizard.com