Dave,

I have a well pump and tank in our sap house that is housed in a 3'x 6' enclosure. Walls are 6" insulation and the hinged plywood top has a piece of 2" rigid insulation attached to it. We have a 14" frost-free sillcock installed for water. To prevent freeze-ups, we use two 100W heavy service light bulbs which are thermostatically controlled. I live on the property so it is checked on a regular basis during winter. No freeze-ups so far.

Russ