It's hard to say if the attic workers caused the problem with the information at hand. Emergency heat is not selected automatically. It is selected by the home owner. It's purpose is to provide auxiliary only heat in an emergency (the failure of the heat pump mechanism). It also prevents the compressor from running if it is still able to do so. It should still shut off when the set temperature is reached. What is the make and model of the heat pump and the thermostat? Are you sure the system was in the emergency heat mode? What was the set temperature before you reset it? How did you rest the thermostat? Was the compressor running when the temp went so high? This information would help with a diagnosis. In the meantime, I would disconnect all power to the entire system at the AC breakers for at least five minutes to reset any electronics in the heat pump itself. If the thermostat has a battery in it, it would also be a good idea to remove the battery at the same time. This will help insure that the thermostat really is fully reset. Sorry about the hamster.

alot of thermostats require the installer to put a jumper wire between the "E" (emergency heat) terminals and the "W2" (2nd stage heat) terminals on the thermostat's subbase. its a common mistake that i see on alot of systems and it sounds to me like its your problem.... heat pump and second stage heat works but no stand-alone Emergency heat? yep,if i were running this call that would be the first place id look. using emergency heat wont give you more heat but it will be your best friend if your heat pump dies . hope this helps

Solution to this problem. When you update your system from single stage to 2 stage, you must have C wire from outside unit. My old single stage system came with 3 wires from outside unit to indoor (blower) and Indoor unit to thermostat had 5 wires. I solve this problem with new wiring the whole house. I install 4 wires from outside unit to indoor (blower) (red(Rh), blue(C), yellow(Y1), purple (Y2) (mine had a purple)); Indoor unit to thermostat install 7 wires, which following below. red (Rh) blue (C) yellow Y1 Cooling stage-1 Gray Y2 (Purple Y2) Cooling stage-2 Green (Fan) white (W1) Heating stage-1 brown (w2) Heating stage-2 If you don't want to rewire, I recommend to get CTK04 thermostat, which will be fine with your old wiring.

I'm leaning towards just heat pump with heat strips. That should be fine for your area. If you plan on keeping it that warm in the house as you say in your OP, I would get the Bosch Inverter heat pump as it produces heat clear down to about 5-6 degrees ambient and very efficient at what it does. Then use the strip heat as you need it. I don't know that you'll find a contractor though for this for a new construction job as Bosch just recently came to the Houston market a few months ago. The distributor network for Bosch is in it's infancy... so there are pros and cons for choosing this brand. For what it does / how it does it --- it's a game changer for my market. (Katy, Texas area) As a comparison --- an average run of the mill single speed heat pump will probably struggle once temps drop into the 20's for any significant amount of time. They are efficient when compared to strip heat (utility bill cost wise) but there are higher limitations with those. I've gotten email notifications from my electric provider that they are estimating my next electric bill at less than $50 for November. This may wind up being my lowest electric bill ever for my power rate of 12 cents per KWH. With that said, I keep it quite chilly during the winter and my house is all electric (no gas at all). I shut it off at night and really just use it to take the chill out of the house in the morning. If it gets really cold here, I will probably just heat the main part of the house over night --- as I have it attached to a 4 zone duct system. (This is to explain the how and why my electric bill is so low -- design of the HVAC system is a big part of it.)