Outdoor fan/compressor not running
#1
05-21-17, 05:14 PM
Outdoor fan/compressor not running
Temps hits 90s last week in NJ! Tried to turn on the "Cool" on my thermostat - indoor furnace fan kicked on but outdoor 15 year old Trane 2ttb0036a1000aa did nothing. Took a shot and ordered a new run capacitor. Installed today and tried again. When thermostat engaged in cool - the indoor furnace fan runs and the Trane unit - zilch - however the Trane unit electromagnetic switch/relay did engage / disengage when the thermostat cool called for AC on/off. Nothing from the outdoor fan or compressor. The fan is not seized - spins freely. Any recommendations for next steps to try would be much appreciated. Thanks.
#2
05-21-17, 05:59 PM
Member
Have you verified that you have 240VAC at the outside unit? It's possible that you may have a blown fuse or circuit breaker. The 24VAC control voltage coming from inside the house controls the contactor (relay) in the outside unit. Since you're seeing/hearing the contactor close when the thermostat calls for cooling, your 24VAC control voltage is present. This indicates that you're probably missing the 240VAC. If you have a multimeter, very carefully check to see if you have 240VAC across the two heavy wires at each end of the contactor. One end is the source voltage (240VAC), the other end is the wiring going to the compressor and condenser fan.
#3
05-24-17, 04:39 PM
Thanks Bob. I got my hands on am multimeter today and tested the continuity of the fuses in the outdoor switch box (near the AC unit). It looks like one of the 25A fuses is blown. I ordered a replacement and will try that as a next step.
#4
05-30-17, 04:32 PM
Changed out the fuse today and voila, power to the unit and now both the compressor and fan are running.....the only problem now is that the unit is blowing warm air! I guess that is an issue for a new thread!
#5
05-30-17, 04:40 PM
Group Moderator
Post it here. Split system or heat pump?
Something caused the fuse to blow.
Compressor and condensor fan are both running ??
If they are both running and the larger copper line isn't cold.... you have a compressor issue.
Something caused the fuse to blow.
Compressor and condensor fan are both running ??
If they are both running and the larger copper line isn't cold.... you have a compressor issue.
#6
06-01-17, 06:35 AM
Split system or heat pump? Split System - Trane XB10 (Mfr 2012)
Something caused the fuse to blow. (Cause unknown - it was blown when I turned on AC for first time this year - system was working last Summer/Fall)
Compressor and condensor fan are both running ?? yes, both are running.
If they are both running and the larger copper line isn't cold.... you have a compressor issue. larger copper line is not cold but the compressor is definitely running, so I guess it is a compressor issue...could it be a refrdgerant low or leak situation?
Thanks for any additional feedback.
Something caused the fuse to blow. (Cause unknown - it was blown when I turned on AC for first time this year - system was working last Summer/Fall)
Compressor and condensor fan are both running ?? yes, both are running.
If they are both running and the larger copper line isn't cold.... you have a compressor issue. larger copper line is not cold but the compressor is definitely running, so I guess it is a compressor issue...could it be a refrdgerant low or leak situation?
Thanks for any additional feedback.
Last edited by bridger84; 06-01-17 at 08:21 AM.
#7
06-01-17, 10:29 AM
Group Moderator
A leak could cause a low pressure issue but that condensor has a low pressure cutout safety switch that shuts the condensor down. Either that has been bypassed allowing the compressor to run with no refrigerant or the compressor has internally failed.
#8
06-01-17, 10:54 PM
Your AC is 2012 and furnace is 2002? The post below says about 15y. did you replace or add that ac? And if you replaced it, was it an R22 AC? I'm just curious if they replaced your evaporator cool with the new AC,
But
first off I would replace the other two fuses generally when they're burning up they weaken the others, id also check out your contacts to see if they're pitted too, I'm assuming it's 1ph but still I'd check. and pj are you sure that unit has a LPS? I know in commercial we do but I'd never really seen it on a residential split but if your suction line is warm there's definitely a refer based issue, do you have any temp diff at all? Or is it just a fan basically at this point?
But
first off I would replace the other two fuses generally when they're burning up they weaken the others, id also check out your contacts to see if they're pitted too, I'm assuming it's 1ph but still I'd check. and pj are you sure that unit has a LPS? I know in commercial we do but I'd never really seen it on a residential split but if your suction line is warm there's definitely a refer based issue, do you have any temp diff at all? Or is it just a fan basically at this point?
#9
06-01-17, 11:20 PM
Group Moderator
The majority of residential condensors has a low pressure switch while only a few have a high pressure switch.
#10
06-02-17, 04:45 AM
Sorry, my typo on the Mfr date of the Trane unit - I meant to type 2002! Entire system is 2002.
The system is essentially blowing room temp air.
Compressor running, Indoor and Outdoor fan motors running.
Copper lines (large and small) - to the touch, feel like they are at ambient temperature.
Thanks.
The system is essentially blowing room temp air.
Compressor running, Indoor and Outdoor fan motors running.
Copper lines (large and small) - to the touch, feel like they are at ambient temperature.
Thanks.
