Heat pumps

Considering the comments to my post...could be...

I guess it can be used down there, while it's not used here in the northeast because of the more moderate climate and lower BTUs required.

Your guy may be different, but I never meet a general contractor who, without real pressure from the client which doesn't happen on anything except a custom build or a spec-built contracted for sale, didn't use the cheapest system he could get. House in TN was that way when we bought it; the initial HP (air exchange) was minimally sized and very low efficiency and we were, consequently, much like your homeowner class above. Was our first experience with a heat pump; we were not impressed.

But, when it failed after some 15 year or so, we still didn't have NG in the subdivision and weren't any time _real_soon_now_ (tm) and didn't really much cotton to having to have the LP tank so we bit the bullet and installed a ground-source HP (Water Furnace brand). While the excavation cost was high because we had to do it around existing drain fields, etc., etc., instead of as part of new construction, when finished it outperformed the old HP even on its best, early-life efficiency by at least a third plus with the waste heat from A/C cycle for hotwater option, it supplied essentially "free" hot water during warm weather. And, exit air temp's from the floor vents, while not quite what one gets from gas/oil forced air, were warm enough there was none of that "chill factor" effect one got from the air-exchange unit that was just above room temperature. Plus, the backup resistance heating units were tied into an outside thermistor to keep them from kicking on at anything above 15F or so and even on the few days there down to 0F they never kicked on.

Newer air-exchange units are far better now that 35 year ago or so when this system was new, but if I were doing new construction anywhere that cheap NG isn't available I'd surely investigate thoroughly the option of ground source HP.

Time to wrap this topic up. Appreciate all the suggestions received along the way. In the end I discovered the problem centered around the thermosta t. A perfectly fine thermostat as it was.

The thermostat being oem grade supplied with the heating system did not hav e battery backup. Hence most likely when the home inspector was doing his job the controlling circuit breaker got cycled. Without benefit of battery backup to hold the settings the device defaulted to factory settings.

Default in heat mode calls for a signal from the furnace or boiler to turn on the circulating fan. This system operating more like electric heating d id not need to wait for that signal which would never come. A simple chang e in the installer setup routine for the thermostat fixed it.

In summary a challenge that took days to identify took about 30 seconds to apply the fix.