4th floor loft

[Jetty]

Does anyone know how to effectively and efficiently use the thermostat on the 4th floor? Anderson Homes told me, but I forget. Thanks!!

[sajensen]

I turn mine on auto and keep it between 55 degrees and 63 degrees. It seems the HVAC system doesnt run so hard when I have both of my t-stats going.

[abwjms]

if all the units are alike then the HVAC is controlled by a gnarly zone controller attached to the plenum above the furnace which takes the inputs from the two thermostats and decides whether to turn on heat (if the tstats are set to 'heat') or AC (if they're set to 'cool'). At first we had been keeping the loft tstat lower (low 60sF) than the main floor one for heating (which we set to our desired temp) and looking for convection to carry heat to the loft. This basically worked, and often the loft would be warmer than the lower 2 floors, but we recently noticed that the furnace seems to work better (longer run cycles to raise temps when we enter, and then less frequent operation) if we keep the loft tstat setting close to the main floor one.

What the zone controller appears to do is that when a tstat for a zone is activated ("call for heat") it opens a gate in the appropriate plenum. So zone 1 is the main floor and the bedroom floor, and zone 2 is the loft (apparently, observing where the plenum ductwork goes). So if you want all the power of the AC or heat to go to a particular zone, then by turning "off" (high for cooling or low for heat) the tstat for the other zone, you direct all the airflow to the zone you care about, because the plenum to the other is closed. (Maybe the deal with the furnace seeming to run more smoothly when both tstats are activated (both "calling for heat") has something to do with both plenums being open and the warm air moving through the air system more efficiently. No, I don't do HVAC for a living so that may be nonsense.)

Note that given the issue with sprinkler pipes in the loft ceiling freezing, it is vital that you keep the loft warm. The easiest way to do that is to keep the loft tstat up around the same temp as the main floor tstat. The regs say 55F as a minimum for liability; low 60s gives you (and your valuable unit) a better safety margin IMO.

[Jetty]

Thanks so much for your help.

[edrutecki]

I had a full system checkup done by United Propane the other week in hopes of finding the reason of some really hidious propane bills ( one month was just shy of 400.00 @ 55 degrees and no one was there). The U.P. tech was very knowledgable and informative, his assessment was to close the loft vents entirely ( hot air still leaks thru) because of the long run the hot air has to take to get to the lower floors. The main thermostat is the only one that can call for heat, the one in the loft only opens and closes vents allowing air into the loft itself. The bottom line according to U.P. is to set the loft slightly less than the main, close the vents in the loft, cut the vents in the bedroom floor to half and everything should run at its most efficient. One last thing of caution is that there is a filter in the lower end of the heating unit that no one seems to have been informed about. To access this filter you must remove the lower cover and disconnect the condensation hose, it is reusable and only needs to be cleaned. I tried to upload a picture but it would not go, so if anyone can tell me how I will post one. This is the only filter in the homes without a loft and the U.P. tech said most of the ones he has pulled out have been quite clogged. Hope this helps.

[GregZerphy]

edrutecki thanks for that valuable information. We were told by an HVAC technician that our units should have been placed on the 1st floor.(more energy efficient) Ours was not installed properly and had several issues that took numerous attempts to correct. We still had succesive $300 monthly bills this winter. Dec/Jan - 0 days at condo and Jan/Feb - 48 hrs at condo. I keep the thermostats at ~52 when it's empty. This is ridiculous.

What the heck do the propane bills look like for the full time residents? They have to be $600+!

We got our Feb/Mar bill this week and it was $90, but it was warmer and I made some "improvements" when I was down in Feb.

[edrutecki]

Zerphy, I spoke with First Class Heating & AC, it will cost about 3,500.00 to convert over to a heatpump with propane for a backup. This should be a much more economical system. I'm kind of wondering if there is enough interest maybe a group deal could be arranged, both of my neighbors are thinking about it too.