1. I had 2 Trane heat pumps (installed May 2002), model TWY036B100A1 (3 ton) and they are coupled with the Trane variable speed air handler and matching coil, model TWE037E13FB. I believe that the heat pump has a scroll compressor. Is it best to protect this type of scroll compressor during brownout periods (when the power goes off for a second or two during a storm) while the unit is operating? I always thought that it is best to wait 5 minutes prior to restarting compressor in order to provide time for pressure equalization; otherwise, the compressor will experience harmful and undue strain. I do not know if my units have "anti short cycle" circuitry built-in. I have read about installing this type of 5 minute time delay relay in the condenser unit between the 24v thermostat wire and contactor. I believe that what I may need is called a "delay on make timer". I also have read that some thermostats have this type of circuitry built-in to the thermostat thus making it unnecessary to wire inside the outside condenser unit. I have only a basic Trane Weathertron thermostat (BAYSTAT 240A) manual 2 stage heat, 1 stage with cool mercury bulbs.

2. Also, is a "hard start kit" recommended for my unit? Will a hard start kit do anything to prolong the life cycle of my equipment?

3. Also, during installation, no filter/dryers were installed. One of the old units had a grounded compressor (burnout?) and the lineset was not changed due to thru-the-wall/ceiling considerations. I do not know if the installer blew out the lines with nitrogen followed by vacuum. Is it true that in my units, Trane already put filter/dryers on both the suction line and the liquid line thus making additional "aftermarket" filters unnecessary?

4. During cold weather, when the temperature goes below 20F, I manually switch over the thermostat to emergency heat. After all, at that low outside temperature, the heat pumps are not putting out that much heat, and I may as well "save" the pumps from excessive run time. What is the device called that I can install outside that can be set to shut off the heat pump when the outside temperature reaches a certain temperature? That way, I won't have to bother to manually switch it off at the thermostat.

All comments and suggestions welcome. Thank you very much for your time and consideration.