0
Usually a minimum of 5: R (24 volt "hot")
G (fan signal)
W (heating signal)
Y (cooling signal)
O (reversing valve: usually energized for cooling)
Many also require a 6th:
W2 (2nd stage of heat--backup heat)
Some thermostats also require
C (24v "common")
More sophisticated systems may also require
Y2 (2nd stage cooling)
The HVAC Veteran
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What is em heat?
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.
What does the EM heat mean on your thermostat for your central AC heating unit?
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.
Ruud heat pump to straight cool with heat strips I have a Ruud heat pump going to what was a straight cool with electric heat strips in a mobile home which has no wiring diagram and has 5 connection?
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.
How does an electric heat pump work?
An electric heat pump can heat up your home during winter and cool it during summer.
Why ac unit is blowing hot air inside the house but outside unit blows cold air?
Sounds like your system is a heat pump. When a heat pump cools in the summer, the inside coil gets cold and the outside coil gets hot. When the heat pump heats in the winter, the inside coil gets hot, and the outside coil gets cold. It sounds like your heat pump is stuck in heating mode. Check your thermostat to be sure it didn't accidentally get switched to heat. It could be the reversing valve inside the unit is stuck, or an electrical control is broken, forcing the reversing valve to stay in the heating position. Perhaps a call to the serviceman is in order!
What kind of thermostat do you buy if you have a heat pump?
A heat pump thermostat.
Why won't heat pump cool?
i set my thermostat to cool, my heat pump start it go to heat but not cool, i think the thermostat. can u help.
Is a programmable thermostat good to use with a heat pump system?
A programmable thermostat works fine with a heat pump. Just remember that a heat pump does not heat as fast as a furnace because of the lower BTU ratings so do not set the thermostat as far back as you normally would. Also make sure to buy a thermostat that has heat pump terminals.
What is the purpose of a thermostat on a heat pump?
The purpose of a thermostat on a running heat pump is to be able to determine the temperature the pump is operating at. This is used for regulating the heats needed.
Why will my heat pump not start when i turn on thermostat?
First, is the thermostat in he correct position for cooling? Is there a red light glowing on the thermostat? There could have been a power surge or outage and the heat pump needs to reset. Turn the power off to the heat pump at the control panel for a couple or minutes then back on again to reset the heat pump.
What type of thermostat does a heat pump with auxilary heat use?
Any brand or make will work if it is 2 heat 1 cool thermostat
What would cause a home air conditioner and heater to run at the same time when turning on the heater?
IF THIS IS NOT A HEAT PUMP SYSTEM... COULD BE; thermostat connecting(calling for) heat and cool together. connnection problem in wires- or bad thermostat. find wiring diagram for t-stat, read up on checking voltage in thermostat in the heat-or cool mode. they are separate. does t-stat have separate 'heat-cool' mode. in other words- do you have to switch to heat mode-or cool mode. if it is a heat pump--ask again with that stated in question.
Can a heat pump thermostat be used on non heat pump air conditioning system?
yes it can but everytime you want heat you have to put it on Emergency Heat..
What could be wrong if central heating and air conditioning when put on cool it blows hot air?
If you have a Heat pump, you must set the thermostat up for "heat pump". Then you must connect all the wires up according to the manual. If you do not have a heat pump, the wiring may be crossed or touching somewhere. Call a local heating and air conditioning company to trace out the problem.
Why is the heat and air system only working on emergency heat?
when running the heat-pump the air blowing from the heat ducts is not hot ( it's to cold for the heat-pump). you have a main furnace and it won't turn on ( is thermostat selected for this source), ( is the power switch for main furnace on ), ( is fuse for this furnace good). If these are good (check thermostat wiring at thermostat, and transformer).
Should the thermostat be set to EM heat if the heat pump has Auxiliary heat?
Emergency Heat [EM] should only be used as a backup if the heat pump fails. EM heat uses 1.5 to 3 times as much or electricity as the heat pump.
Why does a cavalier over heat?
why does my 2002 chevy cavalier over heat after i change the thermostat and the water pump
