PDA

View Full Version : 5 mamp fuse keeps blowing, no issues with outside wiring


TaraDibble
Oct 16, 2009, 12:31 PM
Hi,
Had a storm today and came home to no power. Once power restored everything working except A/C. No power to thermostat; used this site to troubleshoot and found a 5 mamp fuse on airhandler had blown. Replaced fuse, air handler kicked on, blew fuse x2. Saw lots of recommendations on checking lines to outside heat pump, no broken/damaged wires. DH put in a 10 mamp fuse and unit comes on; not comfortable with this temp solution. Any other advice (short of calling HVAC repair)? DH has electrical experience, just not with HVAC. We have Trane thermostat with TWG airhandler (model 037-060? ) and heat pump - probably 5 years old.
Thx,Tara

hvac1000
Oct 16, 2009, 12:44 PM
It is possible that high transit voltage condition expressed itself during the storm in which case the circuit board or other electronic devices might have been damaged causing the fuse to blow. Caution: A 10 amp fuse is not the cure.

I would look for an electrical item that is drawing much more current than normal within the HVAC system. If you find it that will be the culprit.