http://www.xpedio.carrier.com/idc/groups/public/documents/techlit/fa4a-6pd.pdf
I'm afraid your question is not very clear. Your heat pump is basically an air conditioning unit with back up heat strips. If your thermostat is wired correctly and I'm certain it was from the factory, then the AC and heat strips will never come on at the same time. Is it not going into cooling mode? Ruud has wiring diagrams for most all their equipment on the internet. With a little research, you should be able to find yours. The Model # of your heat pump is the key to that.
If you have a heat pump A/C unit then you have auxillary heat and emergency heat. The EM stands for emergency heat, which is using only your electric heat strips or gas heat, depending on your system. The auxillary heat uses your compressor inside of your outside unit. Say the house is 60 degrees inside and you set your stat to 70, the temperature difference is so great that if the heat pump alone cannot satisfy, then the auxillary heat would come on to assist the heat pump. Say you were to get a leak in either your condenser or evaporator coils, your heat pump would not work on the regular heat setting on the tstat. In this circumstance you would want to use just the emergency heat until a service tech can evaluate the system.
You need to check the compressor sticker or plate. If faded or unreadable try the installation paperwork/instructions. Typically you can search by the model number online to find it.
On a thermostat, "EM heating" stands for emergency heating. It heats your house up very quickly, and is costly to run. This is suppose to be used if you've lost heat from your heat pump or if you've turned your thermostat way down and need to heat up your house quickly.
2 tons
2.5
It's actually a 2 1/2 ton heat pump
It's a 2 1/2 ton heat pump.
It is a Goodman 3.5 ton 13 seer Heat pump.
3 ton 12,000 btu per ton, the 36 is the btu's. 3 x 12 = 36
3.5 tons air conditioning. 10 Kw electric heat.
2
2.5
five ton
It is a 4 ton unit.
5 ton