Had heat pump replaced roughly a month agoworked fine until yesterday.the wife says it was 85 degrees on the thermostst when it was set at 78. Told her to check breakerfreon line at air handler and compressor;breaker was good line was not cold or condensating said fan was on but not compressornothing was frozen.told her to turn thermo to off till it cools down.this am said it was cool then it wasn'tnow it is.this is a 3 ton 13 seer r-12 unit...thx rob

The fan relay is stuck in the on position. When the temperature drops the heater does not ignite because the fan is already running and ignition is locked out after the heat cycle starts an the fan turns on

go to system set up then go to calibrate and change temp

The thermostat is following a program. You have to reprogrammed it

go to Honeywell web sit with correct and full m# look for instruction man

Your thermostat should have a hold feature indicated by "hold" on or near the hold button. Once this button is pressed "hold" should be indicated somewhere on the screen. When the hold feature is activated your thermostat should stay at the given set-point indefinitely.
If you would like to use the program feature of your thermostat I need to know the make and model before I can help you.

It sounds like you are low on charge. I think you have a thermostatic expansion valve and you need to check the subcooling, you should have 12 to 15 degrees at 95. At 95 degrees your head should be about 280# for a 12 or 13 SEER unit or higher depending on the effeciency. At 78 to 80 degrees indoor depending on the humidity, that is normal. The valve will open to try to fully feed your indoor coil and it sounds like your head pressure is to low to force enough refrigerant thru the coil.

by dark do you mean off? if so check your breakers

As a general rule set your t.sat 20 degrees below outside temp. Leave at this setting 30-45 minutes. Move down until comfortable no lower than 10 degrees below outside for 30-45 minutes. Unit should cycle normally. If it runs continuously then raise the t.stat 3 or 4 degrees up. The national average is 75-78. I usually keep mine set at 80 during the day here in Georgia and 74-78 at night...