Coleman Presidential Compressor Not Running

[justplumducky]

Presidential Model Number: 6281B801
Serial Number: 2724150

• Compressor not running and hot after a couple minutes or so.
  Condenser fan running normally.
  New contactor relay.
  All wires and connections good (shiny new copper wire in wire nuts - redone recently - all wires have continuity).
  One 35MFD capacitor tests at 35MFD
  One 5 MFD capacitor tests 5 MFD.
  220v (actually 240v) across compressor terminals (red and black cables attached) R, S, C markings not visible (I couldn't see them anyway). Old unit and rusty.
  120v measured from each terminal to ground (all three terminals)

No continuity beeper from each comp. terminal to comp. case. Meter probe attached to shiny bare metal spot on comp. case.

All cables disconnected from compressor, then terminal readings for Ohms test:
Terminals configuration (in case they're all this way) is in the shape of a triangle with the apex of the triangle at the top (blk cable), bottom right (red cable), bottom left (smaller brown cable, connected to 35 MFD capacitor).

Would the terminal that's connected to the 35MFD capacitor be the common "C" terminal?

• blk - red: .8 ohms
  brn - red: 4.3 ohms reading fluctuated to a bit higher and back, like 4.6 or so).
  blk - brn: 3.7 ohms

Might this compressor start up with a super-boost capacitor? If it does, is it likely to lock up again in the future?

[Robert]

Have you thoroughly cleaned the condenser coils this way:


http://www.mobilehomerepair.com/hvac/ar ... ioner.html



Thanks,
Robert

[justplumducky]

No I haven't Robert. I was assuming since the compressor doesn't run at all (it won't start up), that a dirty condenser wouldn't come into play. If that's what you want me do, that's what I'll do.

Let me guess: Something on the order of it possibly being pressure-locked due to dirty condenser and recent hot weather?

Thank you.

[Robert]

With the info given, felt it may be out on internal overload due to dirty condenser/high head pressure.

IF it had never run or been down a long time, it would at least start up. Your saying it was Hot led me to believe it had recently been running maybe.


IF so, needs to be cleaned good.


IF still no go, check the amp draw on it and see if it is pulling locked rotor amps maybe.


The super boost start assists can sometimes get it going IF not dead yet. As for how long it will last, can be a day to a few years.

If and when you install a booster, start saving for replacement because it is in the future.


Always get a 3 wire, not the 2 wire and the 5-2-1 series work good.


Thanks,
Robert

[justplumducky]

My apologies for the oversight and lack of info.

I also had done the amps draw and it wasn't pulling hardly anything at all (literally), but I didn't get the clamp meter on it until after it had started, and if I understand LRA (I Googled for it), that's only momentary and then it goes off on overload? So I'd need to get the meter on it before startup?

Anyway, I cleaned up the condenser and it didn't help, so I got a booster, but only a two wire. I should have waited to talk to you again. It started hard (shook side to side momentarily), then smoothed out, then the next time started easy (I waited a few minutes before restarting). It sounded fine while running, but upon shut down, made a whistling noise which turned, very gradually, into a deeper howl with fading intensity and volume, then silence.

Thank you.

[Robert]

Hi,

Get a 3 wire or the 5-2-1 series for your unit. It won't start if locked rotor. Sounds like it is time to have an hvac tech test system and compressor thoroughly to know if it is finished or if something in system is causing the problem.


Thanks,
Robert

[justplumducky]

Ok then, thx so much for your help Robert.

Justplumducky

[Robert]

You're very welcome, happy to help.



Thanks,
Robert