How do I fix heat on unit Frigidare Model LRA12HZT2?

Either give more information such as type of unit model # or call a tech .

Those window units usually have a strip heat kit that supplies the heat. You might want to have a technician open up and check heating circuit.

Probably a bad limit switch on the strips or the heat sequencer/relay is falling out after continued amp draw. I would lean toward the heat relay/sequencer. Havent heard of any problems with coleman limit switches. These units were prone to get water inthe electrical compartments due to the evap coil being right above it. Check to see where the power break is starting at the strips and working backwards throught the circuit. That will tell you for sure. Make sure you have 24v going to the heat sequencer too.

Behind the evaporator there will be heat strip. Unscrew top cover and top sheet on the evaporator coil. Now you can see.

Basically, set unit to call for the heat strips to be energized. There should be a control that sends power to the heat strips. Usually a contactor or relay. Verify that power passes thru this device to the heat strips. Make sure that the correct voltage is being delivered to the heat strips. If correct voltage is present at the terminals of the heat strip, check the amps. If no amps, heat strip is probably broken. Don't forget that some of these units have sequencers that "Stage" the energizing of the strips. And all of them should have some safety device such as a fuse or thermal overload or some other device that stops voltage should there be a malfunction.
Hope this helps.

I believe the unit you are describing is a heat pump. Heat pump are great when the temperature isn't below 30 With low ambient temps. outside it is much more efficient and comfortable to run aux. electric heat from the heat pump.

heat strip is possibly burnt out and will need to be replaced. The strip sits inside the unit right behind the evaporator coil, To access the heat strip you will need to remove the unit from its casing and place it on a level surface.. The heat strip is possibly in a metal casing and the heat strips look like the heat strips in a toaster. The assembly comes out by removal of a few phillips head screws and has an electrical disconnect plug that powers the coil. Take the coil assembly along with the model and serial number to the nearest appliance parts house for replacement part. Good Luck hope this helped you somewhat

Dave

If it is a heat pump, the compressor will be running both in cool mode and in normal heat mode.

Confirm the current indoor temperature. Turn the thermostat up one degree at a time until it comes on. This will typically be 1 to 4 degrees increase. As soon as it comes on stop increasing the temp.

If the compressor is running, it is a heat pump.

Check the temperature coming our of the vents at that time. You should have 30 to 60 degrees increase from the air temp going into the unit and the conditioned air temp coming out.

Then turn the T-stat up another 10 degrees. If the temp coming out of the vents increases by 20 degrees or more. the strips are on.

The strips operate in three situations.
1) the system is set to emergency heat
2) The heat pump cannot keep up with the demand for heat. (because its too cold outside, the desired temp setting is greater than 4 to 8 degrees above the room temp, or the HP is malfunctioning.)
3) The HP is in defrost mode

You could also take the panels off the unit and look for a reversing valve, but unless you know what you are looking for you will not recognise it.

Need to order the resistant heater, use the mothel of the unit to make the orther

If you are looking for a "window" type of unit yes there are some 220 volt units on the market. Most are large like 18,000 btu or larger. Check Lowes, Home Depot or larger appliance retailers for availability. Also know when buying if you need a heat strip, or heat pump if indeed you want heat.