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Titan 77 · 11-29-2013, 11:14 AM

I have a carrier air v low profile air conditioner I bought used. I have it setup on some saw horses in the shop so I could clean it up and test run it to make sure it works okay before installing it on the motorhome. This is an air conditioner only & has a non-ducted ceiling cover.

Everything seems to work except for the large black fan on top which I believe is supposed to keep the compressor & condenser cool. My question is whether this fan should run all the time or if it is themostaticlly controlled to run when the unit gets warm. The fan spins freely, but hasn't run when I have done the test run. The temperature is cold here now so I'm not able to test my theory. I have also not heard the compressor kick on and off... But again, that could be due to the cool temperatures.

Thanks in advance to anyone who has any ideas or advice on this!

powerboatr · 11-29-2013, 12:24 PM

Quote:

Originally Posted by Titan 77

I have a carrier air v low profile air conditioner I bought used. I have it setup on some saw horses in the shop so I could clean it up and test run it to make sure it works okay before installing it on the motorhome. This is an air conditioner only & has a non-ducted ceiling cover.

Everything seems to work except for the large black fan on top which I believe is supposed to keep the compressor & condenser cool. My question is whether this fan should run all the time or if it is themostaticlly controlled to run when the unit gets warm. The fan spins freely, but hasn't run when I have done the test run. The temperature is cold here now so I'm not able to test my theory. I have also not heard the compressor kick on and off... But again, that could be due to the cool temperatures.

Thanks in advance to anyone who has any ideas or advice on this!

Service Documents and Manuals
go to the above link and download the repair book, your answers should be in there, i would suspect outside temps does effect the fans coming on or off, but

Miljet · 12-01-2013, 07:17 PM

Have you hooked up any kind of thermostat to the unit? It needs a 12V DC control circuit.

94-Newmar · 12-02-2013, 03:48 AM

Quote:

Originally Posted by Titan 77

.....This is an air conditioner only & has a non-ducted ceiling cover.

Everything seems to work except for the large black fan on top which I believe is supposed to keep the compressor & condenser cool....

I have also not heard the compressor kick on and off... But again, that could be due to the cool temperatures.

So the evaporator motor/fan is working but the upper fan for the condenser and compressor are not?

As mentioned, did you obtain the thermostat for this unit too? I am wondering if you are indeed getting a good call for cooling or just fan only mode as there is no thermal "test" for the compressor to the upper fan - both are engaged in the same circuit. If the compressor is obtaining power, then the upper fan is being energized as well.

Using the wiring diagram posted here: http://www.transportaircon.carrier.c...US-en/T298.pdf take a close look at the PTC shown on page 4-1. Make sure the thermostat you're using is wired correctly, the diagrams are all within that link above.

Titan 77 · 12-03-2013, 11:26 AM

Thanks for all of the replies! I hope everyone had a great Thanksgiving!
And yes, 94-Numar, you are correct, the evaporator fan is running but the condenser fan does not.
I downloaded & printed the service manual and have had my head stuck in that for a couple days. I really haven't found any mention as to whether that condenser fan should run all the time or just when the compressor & condenser coils need cooling... It seems as though it should.
There was no thermostat included when I got this, & I assumed it was contained in the ceiling controls, as this is a non-ducted, non heating unit. I will explore this further. I will also run some voltage checks to verify if there is juice to the condenser fan motor to determine if it could be faulty or if I have a problem elsewhere.
Again, thanks for all your input... I shall return!

The Titan

94-Newmar · 12-03-2013, 05:00 PM

Yes, if you have the inside controls with knobs then you do not need a seperate thermostat. Good luck with it and post your resolution(s).

hnybare · 12-04-2013, 02:20 PM

I guess I didn't read where the compressor was coming on when the indoor fan was running. It is possible the fan in question only runs when the compressor is in operation.

Titan 77 · 12-05-2013, 11:09 AM

I don't believe the compressor has kicked on due to the fact that that there really hasn't been any demand for cooling where I have been testing it. It ran for approximately a half hour or so, & in that time I never heard the compressor kick in. The ambient temperature in that area was probably around 65 maybe 70. So it is very possible that I haven't loaded it down enough yet as for it to start.
I haven't had the chance to run any voltage checks yet & I may try to get it to a warmer place to try and place a little more demand on it.
I hope you are right hnybare!
Thank you!