I have a Carrier 38YRA060300 SN 1995E00033 (is that a 1995 unit?) The quick: Does it need a 40 Amp Contactor or can it get by with a
30 Amp Contactor?The long and involved: I just had some service done on the unit. The compressor (and compressor fan) was running even though the thermostat was in the off position and had been in the off posistion for several hours.
This is the second time it has happened. The first was last Christmas and the tech installed a new controll board. (I don't think he wanted to be there (it was christmas eve and raining...)) (My appologies to the HVAC techs of the world, if it was not the heat I needed, I would have waited until the next business day)
The unit seemed to work when he was done, but we noticed the same problem this last weekend. Called the home warranty company back, they sent out a different technition from a different company (I think) and this tech replaced the contactor. Based on posts in alt.hvac, this seems to be the correct diagnois this time and from looking at the old contactor the right part was probably replaced. (It was pitted and had some scorch marks).
While the tech was installing the replacement contactor, I looked at the old and new contactor. The new contactor was significiantly smaller than the old one, so I looked closer and could see that the old unit was rated for 40 FLA/50 RLA and the new unit was rated for 30 FLA/40 RLA. I did not look closely at the LRA rating, but I assume that these parts are pretty standard. When I asked the tech about it he said that he was putting in a 40 amp part even though it clearly stated it was a 30 amp part.
If you are interested the part numbers of the contactors were: New: WRNO 6590-244 (acording to the Tech) Old: CR353ADY35H or HN52KD025A (the only two numers that looked like part numbers on the contactor)
The plate on the Compressor says: Compressor 34.9 RLA 169.0 LRA Fan: 1.5 HP: 1.4 FLA
And a measured running/startup amps for the unit last year was:
20Amps Running, 172Amps Startup.So the question is, is the new 30Amp contactor sufficient (from the plate it looks close (34.9 RLA + the fan vs 40 RLA)) or do I need a 40 Amp contactor to avoid future breakdowns?
Option 1: Call the tech back out with a new 40 Amp contactor. (a potential waste of my time when they can only come out between 2 and 4 in the afternoon).
Option 2: Go buy my own 40 Amp contactor and do it myself. (a waste of my money, but can be done on my schedule). (If this is the option I should take, I guess I should have read the news groops first and done this the first time around...)
Option 3: Leave it alone, the 30 Amp contactor will last for years and won't cause a fire.
Thanks for any help....
RBV