Is this oil heat? If you're having to hit the reset button repeatedly, you have a more serious problem - likely nothing to do with the thermostat. If it's a zoned forced air system, an improperly wired thermostat will cause it to behave improperly. As was mentioned - there's nothing that needs to "cool down" or rest, your furnace can run non-stop w/out issue, BUT, it needs to be running right or you could find yourself w/ out any heat at all in a bit. If you're pushing the reset button, there's clearly something not right.

Yes if you have a higher pressure it is easer to push the air out. its the same way to circulate, if you pressure is to low it will not want to flow to the upper story, especial if the pump is too small. If you go to the hi velocity pump,and thats what i always use in a three story house, you will have one little thing you may not like. On a zone system , when only one zone is open you might hear a little water movement noise depending on you piping system. Engineering will vary from one engineer to another a little. But i am going to give you some facts. normal hot water system no more than 30' to 40' of radiation on one 3/4 in. loop or zone and standard zone values 3 to 3 1/2 gal.s per min. . Now if you have too long of loop you will slow flow down and lose too much heat, same if you have too much radiation on a loop. You said three story two zones. this sounds like long loops which means hi head pressure, and maybe too much radiation per zone. some times when i run into this i advice the owner that we will have to switch the zone values to a full flow zone value, they go up to about 7 gal.s per min. flow, this along with the hi head pump will take care of too much heat loss,and too much head pressure. I hope all this is not confusing you too much, But hot water in a older home can be a little complicated. and a lot of guys do not understand this. You can check a zone out one way by checking the temp leaving the boiler and then check the temp. coming back from the zone. no more than 15 degrees drop.. Later Paulbm

The tech just left and this is what I was told. Our furnace a Trane XE 90 model:TDC080C942B1 is a 80,000 BTU furnace and the problem is the amount of duct work going out of the furnace. It is a down flow furnace and I looked below and saw we have 1 ten inch, 1 eight inch, and 5 five inch duct work going out of the furnace and the eight inch actual had a metal piece over it turning it into a five. So I was told the furnace needed 1200 CFM outflow based on the furnace sized and before we removed the metal from the eight we were at 725 CFM available ductwork. So that is why we are overheating? The fan was turned up to high and that did not help. Because our house is a slab and the ductwork is in concrete our options are to get a new furnace, bust out the floors to add duct work (not an option). The heat exchanger is not cracked, the blower wheel is clean, the secondary heat exchanger was clean and the coil was also clean and gas pressure was checked. I was shown all of this. What should we do? The furnace was installed in 1995. We are getting heat and donÂt have complaints about the heat. But we do live in North Dakota and I hate to wait for it to fail and it be 30 degrees below zero and a Saturday. Should I get a second opinion, given it will be about 100 bucks to get someone to come. Any thoughts would be great.

The compressor will run continuously when a balance point is reached at which the heat loss of the house is equal to (or more than) the output of the heat pump. If the heat loss rate exactly equals the output rate then it will run continuously and exactly hold the setpoint but the auxiliary shouldn't need to engage. If the heat loss is more than the output rate then the auxiliary will cycle on when the room temp falls far enough below the setpoint and cycle off when the room temp rises enough to shut it off ... although the heat pump will continue to run for duration until the room temp rises enough above the setpoint to cycle the entire system off. The thermostat, as you may know, has two separate sets of contacts ... one set for the heat pump compressor & blower and another for the auxiliary. Typically the differential is approx 2°F. Thus if the setpoint is 70°F, the auxiliary will trigger if the room temp drops to 68°F-ish because the compressor alone can't handle the load. The auxiliary cycles off when the temp rises by approx 2°F, although the compressor may not cycle off because the room temp typically must rise a little above the setpoint (70°F) to cycle the entire system off. Some electronic thermostats may trigger the auxiliary based on run-time ... that is, if the compressor has been running for X period of time and room temp setpoint hasn't been reached to cycle the system off. Running continuously and holding the setpoint or within a degree or so of it isn't to be considered a problem. Technically, it's more efficient to run continuously.