Air Conditioning - 5 Ton Trane Heat Pump blowing 5 amp fuse

I have a upstairs unit. Daughter came home from college
Upstairs is her bedroom and a sitting room
I cut the unit on yesterday to be warming up.
Last night about 2am
she comes down awakes me tells me its COLD and the unit is off..

In the morning( I'M OFF WORK as in laid off work).. The unit is in the attic,I go up crawl like a snake on my fat azz belly.
Get to the unit take off the side panel.
The 5amp fuse is blown
I put another fuse in it and unit comes on. I go out and do feel warm air coming out..

Daughter has told me sometimes the unit is running and I have done feel Cool air coming out.
This is long I know but wanting to give the facts..

Any Ideals I can do before I call the man..
Money so tight right now. Is there something I can check?
I did change both unit and return filters 2 months ago.

Thank you for reading
Dave
731-695-5658

Can you give me a better idea of the control wires? Do they come up through a wall at a sharp angle and are they tight? Do they run across and to the unit on any sharp edges?
The reason being, it sounds like you are getting a short in the T-Stat wire. With the wire insulation being torn to expose bear copper wire. Sometimes the wires do not short until the fan kicks on and the wire run (unprotected in the return air) will rub and short out the fuze. This is a overload protection for the step down transformer so do not bypass it. Check the wire and report back.

HAPPY, send me your home email and I will email you a pic of it.
Thank you for your reply
Dave
rave@usit.net

I noticed this..
I cut the system on it blows out warm air.
I sat in there a while with it running and blowing warm air out.

Afte 30 minutes or so I hear the system click/jolt then COLD AIR startscoming out.
I let it run a bit then go to the thermostate cut it down
the unit cuts off.. Later it will cut on and warm air comes out
then does the same deal.. it jolts and then cold air comes out
and it stays running.. This time I let it run cool air
about a hour I re-did the above and it started with warm air.

Could this be Thrmostat going bad and not shutting off when suppose to??
I'm going into town and would rather spend money buying one of those if its it instead of paying a service call..
Time I get back home tonight id like to have it. If that may be it..
Dave
Tennessee
731-695-5658

OK, THis is a heat pump so it "clicking and then blowing out cool air after 30 min. sounds like a defrost cycle to me. THis is normal, however there should be an aux heat to temper the air. Look at your heat pump, you should have a heat stip inside the front door. With the power off to all units check to see in you have resistance through the heat windings.

Dave I sent you an email, are you sending pics?

Does your thermostat have an Emergency heat mode setting? It should. Set it to emergency heat, zoom it to 90F. Let it run for 45 minutes...is it pumping heat? If yes, it will eliminate the heater section. Sounds like Mr Happy has seen this before as have I. The insulation on the stast wire is very thin and when the shell is stripped back, many times the installer knicks the insulation of the conductor or it has become brittle from the attic heat and is touching metal somewhere and grounding out and blowing the fuse on the control circuit. The other possibility might be the contactor coil in the condensing unit which is common. I had a customer hang a picture and drove the nail between the conductors and shorted the transformer.

Yes it has a Emergency heat button.

In talking to my daugher, she said when she awoke up COLD at 2am UNIT was running but real cold. It was blowing COLD AIR.. The outside temp was about 26 last night..
When my daughter tried to turn the thermostate up that is when the unit shut off..

Happy I have not got the pic yet.. I got to wrap up slide down the edge about 25' then I can get on my knees to the unit. I will

Could it just be low on freeon?? why it won't stay warm??

I doubt it is low on refrigerant due to it blowing warm air. Do you have a multimeter? If so disconnect the T-Stat and do a continuity check on all wire stating with red to yellow, then red to orange or what ever collor wire goes to the O terminal, that wire controls the reversing valve. This will save you from the long crawl.

Heat pumps work like air conditioners during the summer and reverse to become air heaters during the winter. During the summer, refrigerant is piped through the indoor coils, absorbs heat from the room air, and vaporizes. The cooled room air is then re-circulated in the house by a blower. The vaporized refrigerant flows into the compressor, which pumps the refrigerant to the outdoor coil, where it condenses back into a liquid by releasing its heat to the outdoor air. Air is circulated through the outside unit by a fan. The cooled refrigerant then flows back to the indoor coil, where the heat transfer cycle is repeated.

In the heating mode, the refrigerant flow is reversed, bringing heat inside from outdoors, essentially working like a conventional air conditioner in reverse. Cold refrigerant is piped through the outdoor coils, absorbing heat from the outside air. The refrigerant vaporizes and flows into the compressor, which pumps it to the indoor coil, where it condenses back into a liquid by releasing its heat to the indoor air. The refrigerant then flows back to the outdoor coils, where the heat transfer cycle starts again.

Like refrigerators, most heat pumps have defrost cycles that minimize frost buildup on the evaporator during the winter heating cycle. Defrost occurs automatically at pre-set time intervals. Defrosting works against the efficiency of the unit when it switches into defrost mode unnecessarily, wasting heating and cooling capacity. Microprocessor controls in some units prevent this from happening. Some controls even determine whether the heat pump or back-up heat is more economical at a particular outdoor air temperature and switch to that heating system.
Beer 4U2

Thanks for the information. right now it is running fine.
I will keep ya posted

I have a heat pump that is also blowing cold air. I checked the breaker from inside the house and it was off. I fliiped the breaker and it kicked it off again. 2 days ago i had heat, but last night the break kept kicking off. On a couple of occasions the breaker would stay on and the fan on the heat pump was running, but within a minute, it kicked the breaker again. Any thoughts?

Sounds like you have an electrical short to ground. More than likely run to common in the compressor.

don't keep resetting and popping the breaker. Switch it to emergency heat and get oit looked at. Its likely the compressor. If it pops in emergency, its NOT the compressor but needs attention.