Not all compressors have heaters. Scroll compressors do not absolutely require them, although some are equipped with them. I own one system that does not have a heater. Units with compressor heaters sometimes disconnect and reconnect power based on logic. One system I am aware of disconnects heater power after the compressor has run for a specified time (I forget how long). Once the compressor shuts down, a timer is started. If the timer reaches the one hour mark before the compressor restarts, the compressor heater power is reapplied. You should review the technical literature for your system to determine if it has a heater, and how it might be controlled if it exists. It is always a good idea to wait a short period to let the system equalize before restarting a compressor after a power failure, although this too is something that scroll compressors don't absolutely require. High end systems usually automatically enforce a restart delay. Better thermostats do too. Just watch out for stuff like the RiteTemp models that forget the delay if there is a power failure, just when it is needed most.

Wow, you gentlemen respond very quickly. Thanks for that. And apparently, I'm not at my sharpest in the middle of the night. That power rate was incorrect. I only provided the fuel charge. Adding all the pieces together comes to $0.11579 (.0782 summer rate, .00144 transmission rate, and .03615 fuel charge). As for the other questions/comments: * I did worry about the lineset diameter and confirmed for the length, turns, and elevation change online for the Lennox. It won't even have a 1% drop in efficiency. The Bryant salesman with 17 years experience told me the lineset works. All the contractors told me the lineset works for a 2 ton but not a 3 ton. Additionally, replacing the lineset adds roughly $1,000 to each bid. * Only one of the contractors specified a 3 ton unit and there expected the unit to always run in the low speed except during extreme circumstances. * The Bryant does come with the Evolution controller t-stat. * Demand defrost - I couldn't find any mention of this for the Lennox online, so I will pose the question to the contractor. I did find this text on the Bryan installation instructions -> "The control board accumulates compressor run time. As theaccumulated run time approaches the selected defrost interval time, the control board monitors the coil temperature sensor for a defrost demand. If a defrost demand exists, a defrost cycle will be initiated at the end of the selected time interval. A defrost demand exists when the coil temperature is at or below 32_F (0_C) for 4 minutes during the interval." * I will ask about the staged heat strips. Austin generally only has 24 hours or less below freezing and maybe two months where heating is used. * Tigerdunes - what do you mean when you say the prices are "very frisky"? * We certainly are having more and more hot summers. It struck me that at least a couple of the contractors were eager for the business as they were ready to do the work within a day or two. How over priced do you think these prices are for premium equipment? I am leaning toward the Lennox due to the 10 year warranty for labor and the Internet enabled thermostat that allows me to adjust it from my iPhone when I realize we are out of the house for a while. Additionally, the salesman was more pleasant to my wife and helpful to me without the constant adjustments in what he is selling me. Thanks again for all the advice. It is invaluable in making sure I get my money's worth. Regards, Trevor in Austin

mac I have an Econar GT heat pump in a second floor closet and had noise issues that were aweful. It turned out to be improper vibration dampening when the system was installed. The scroll compessors run between 50 and 60 cycles per second. The 3 stage fan in my 3 ton GT unit runs in the 1100 to 1800 RPM range (or 18 to 30 cycles per second). The guys who did the install laid the GT unit on the floor and put a rubber mat under the base. That mat became essentailly a vibration noise amplifier. I found that rubber can isolate very high frency vibs - not the lower frequnecies. The rubber is recommended at a minimum of 45 Hz - but it really doesn't work well until you get above 60. I know this is the case becuase my loop pumps in the basement run at 60 Hz and they are on rubber mats too - no vibration noise (there is acoustical noise from the impellar spinning - but that has to be dampened by other means). My solution was to jack up the unit - get if off the floor by 5 inches or so - and put vibration isolation mounts with springs on each of the 4 corners. These springs can dampen vibs down to a few Hz and up to 60Hz - they are much more effective then rubber in the frequnecy range of the unit. That fixed the problem. You can still hear the unit for the first 3 to 5 seconds after it first turns on - but once it is in steady state, it purrs. No louder than the hum of a refrigerator. My builder and HVAC contractor were stunned - appranetly they have this same issue in other houses they built with GT where people cannot sleep (but never told me that when they sold me the GT)! I think they owe me one. Your issue sounds similar to mine. Can you describe how the unit was installed - where it is, what is it resting on? What type of floor is it on - is it in a closet? Is the closet insulated? The site I used to but these products is www.acousticalsurfaces.com. Look under Vibration Mounts and then look under Housed Spring Mounts. The product is made by Mason Industries and needs to be chosen carefully based on your units corner weight. You need to determine if the noise you are hearing is acoustic noise or vibration noise. If it is acoustic noise - then you can use sound proofing insulation. If it is vibration noise - then you need dampeners. I used both - the walls of the room have insulation to dampen acoustic noise. The springs dampen vibration noise.

DavidAndKasie is correct. Heat pumps CAN be set back (turned down) effectively with a setback thermostat that has smart recovery. First, since you say that you don't understand much about how heat pumps work, let's cover that. A heat pump basically is the same as an ordinary airconditioner, with the addition of a reversing valve that changes its functioning to HEAT the indoors instead of cooling. Air conditioners don't so much MAKE cold as they MOVE heat from one place to another. In cooling mode, heat is moved from inside to outside. That's the hot air you feel blowing from the unit outside (the inside blows cool air). In heating mode, the unit picks up heat from outside and moves it IN (the outside unit blows COLD air, the inside WARM). There technically is heat in the air (or an object) down to scientific absolute zero (-459.67F) when molecular motion stops. It's cheaper from an electric energy expenditure point-of-view to MOVE heat than to CREATE heat. Thus heat pumps are cheaper to operate electrically than glowing-red heating elements. However, when the outdoor temperature drops, particularly to the point of ice/frosting, it's harder for the heat pump to pick up the heat and move it inside. So all heat pump system have an auxiliary heat source, typically standard electric heating elements, that activate as needed when it can't maintain the desired indoor temperature without help. This is called the "balance point" -- the point at which the heat pump can't move heat in fast enough from outside to counteract the heat loss that's occurring through doors, windows, walls, etc. Every system and house is different in that respect. The indoor temp drops below the setpoint (thermostat set on 70°F, room temp is 68°F for example), and a 2nd pair of contacts trigger in the thermostat which turns on the heating elements. Electronic thermostats may also do this based on time. If the system can't reach the setpoint (70°F) within a specific time period, or the thermostat senses that the indoor temperature isn't increasing or isn't increasing fast enough, the elements turn on. Of course, the heating elements pull a lot more electricity and aren't as efficient as the heat pump. So the trick after a setback (or having turned the system completely off) is to raise the temperature SLOWLY so the heating elements DON'T turn on. Electronic setback thermostats designed for heat pumps do this automatically. The computer figures out how soon to start the recovery process so it can raise the temp slowly and hit the target at the specified time without using the auxiliary elements (or minimizing use of them). It may take a few cycles for the computer to "learn" the characteristics of a particular system and get the timing right. You can also do it manually, but you have to PAY ATTENTION and not raise the temp too fast or too high at a time. This may take a couple hours at lower outdoor temps. Beware also that if the outdoor temp is well below the aforementioned "balance point" the system may NOT be able to recover the desired indoor temp at all without use of the auxiliary heating elements. Another aspect of heat pumps that you should know about is defrosting. As mentioned earlier, the outdoor unit in heating mode is basically cooling the outside. During some conditions, particularly wet/freezing weather, the coils can ice-up, like a food freezer that needs defrosting. Air can't blow through the coils when they're clogged with ice, so like a freezer they must be defrosted. The system does that by switching back to AIR CONDITIONING mode for a few mins so the outside coils get warm and melt the ice. Now remember that when running as an air conditioner, the system blows COLD air inside the house. During defrost, the auxiliary heating elements turn on, NOT for the purpose of melting the ice on the coils outside, but to warm up the cold air that would otherwise be blowing in the house. There's no way to prevent defrost from happening, the system does that automatically as needed. Some people say that if the outdoor temp is so low for an extended period that the system is running continuously, the outdoor unit is repeatedly icing over and defrosting, then it's best to set the thermostat to Emergency Heat, which shuts off the heat pump and runs ONLY the heating elements ... since they're being used a lot anyway during the frequent defrost cycles.