2020 Navion 24J A/C Issue Query…

[Danjuan]

Hi Fello Winnie’ People,

I have a low mile 2020 Navion with a Coleman Mach 45000 that has rarely been used.
AC…..
It blows air, both speeds, but no cold at all. When AC is trying to start it kills Onan generator, on grid it eventually blows breaker. Three capacitors all test fine. The unit tries to cycle and turn on but compressor won’t start although voltage is getting to it.
Maybe capacitors aren’t getting their charge ?
Any thoughts ?
Controller thingy ?
Question is ; if I need to trash old one and buy new, which one replaces the existing one ?
Present unit :
Model # 45053-8792
Serial # 200109385

Thanx,

Danjuan
Anacortes, WA.

[creativepart]

Likely a failed compressor. There is a two year warranty on Coleman-Mach A/C units. So, any chance you got in under that wire?

It is a common issue and can easily be verified by a RV tech. They take certain amp readings and can tell you right away.

Generally they are not repairable and are just replaced. Though there are urban legends that some folks remove them and take them to an independent A/C shop and get them fixed. But the vast majority just buy a replacement.

[Danjuan]

Got that, what I was afraid of.
Sad they can’t be repaired and charged ( legally ) any more.
Toss & replace society, it is now..
Bought it ( little ) used in 21’ and just never had reason to try till 23’, figure warranty is long gone.
Thanks for the reply.

[Ray,IN]

OH, they can be legally repaired,(R134A refrigerant is legal) it's just not financially reasonable to put the same amount of money in repairing any used RV air conditioner/heat pump that the same money will buy a new unit.

[Danjuan]

Thanx Ray, afraid of that part too, ye gadz..!

[Sparky19053]

Look on the bright side, maybe you can find a quite version for your replacement.

[Danjuan]

Originally Posted by Sparky19053

Look on the bright side, maybe you can find a quite version for your replacement.

Ya, thanKs, nice consolation prize perhaps.

I’ll just be greatful for cold air at times !

[creativepart]

Originally Posted by Sparky19053

Look on the bright side, maybe you can find a quite version for your replacement.

Oh, if it were that easy. Not only is it difficult to get good numbers and reviews for how quite RV A/C units are, but also there’s a catch. You have to find one that works with the thermostat and it’s wiring as installed in the RV.

[eyecando]

Don't give up on that unit yet! I would double check the capacitors. It's also possible the PTCR device has failed. It doesn't take much to bog down the generator. Do your testing while on utility power. Repeat the test on utility power!

Sometimes a capacitor will fail open or short under load, but the capacitor tester shows it good. It's possible the compressor may have failed, but using the generator to help diagnose the issue may lead you the wrong way down the road. It could be that the AC unit is just drawing a little to much current.

I have been down the same road before with my 2020 Navion when the generator bogged down starting the compressor only to find out later, there was no issue after I ran it for a while on utility power.

Replacing the capacitors could be an inexpensive fix. Verify the PTCR resistor is not open. If I remember correctly, the PTCR resistor has a fairly low resistance when cold but it increases in resistance when it heats up with current flowing through it.

[Danjuan]

Thanks for that word of hope yet….

Ya, I had the feeling there was zero charge in all three capacitors when I grounded them out to discharge before testing them with ohm meter. I don’t know what you mean by;
PTCR unit, is that the control unit ?

[eyecando]

Originally Posted by Danjuan

Thanks for that word of hope yet….

Ya, I had the feeling there was zero charge in all three capacitors when I grounded them out to discharge before testing them with ohm meter. I don’t know what you mean by;
PTCR unit, is that the control unit ?

It’s a temperature controlled resistor connected to the capacitors. Also, you can’t verify capacitance with an ohmmeter.

Replace the capacitors and verify the PTCR device is not open.

There should be a diagram showing the component hookup on the back of the door to the capacitors. You can also go to the Coleman site for some information.

Mike

[Morich]

Sounds like you may be doing okay with the testing you have done> I assume you are using the right type ohmmeter? Analog meter?

But I might add a note of caution before jumping to replacement as most of us who don't do Ac very much can totally miss some really simple problems that might make us spend big bucks and lots of time!

Testing the caps may get a start but it may miss something as simple as the connections or wires to those!
Careful and it may pay to spend some small amount to let a pro look before spending the big bucks!

[Danjuan]

Originally Posted by Morich

Sounds like you may be doing okay with the testing you have done> I assume you are using the right type ohmmeter? Analog meter?

But I might add a note of caution before jumping to replacement as most of us who don't do Ac very much can totally miss some really simple problems that might make us spend big bucks and lots of time!

Testing the caps may get a start but it may miss something as simple as the connections or wires to those!
Careful and it may pay to spend some small amount to let a pro look before spending the big bucks!

Gooday Morich,

Ok, thanks for that encouragement, I will go back up with a new mind set and a better tester. And, yes, I used a cheep digital ohmmeter and wondered if it was giving me correct readings. It’s a relatively new machine so, I’d rather not be one to replace the whole thing because of a cheep or free malfunctioning item.

Oh, and… if you happen to see a cute blond chick and her guy, Austin, running around Austin TX in the next few days in a converted short bus “Schoolie”, blue-green, why, give them a wave and thumbs up. They too, are headed for the big event on Monday!

[Danjuan]

Originally Posted by eyecando

It’s a temperature controlled resistor connected to the capacitors. Also, you can’t verify capacitance with an ohmmeter.

Replace the capacitors and verify the PTCR device is not open.

There should be a diagram showing the component hookup on the back of the door to the capacitors. You can also go to the Coleman site for some information.

Mike

Thank You Mike,
I will order all three capacitors, instal them, ( must admit, I’m a-feared of getting a big jolt ⚡️) and look for, and test the PCTR.
Appreciate your advice.
I might not be an electrical engineer but I am stubborn and would rather not throw good $$ at a whole new unit because of simple malfunction.
It might be a few weeks but I’ll let ya’ll kno if it worked.
Dan

[Sparky19053]

Originally Posted by Danjuan

Thank You Mike,
I will order all three capacitors, instal them, ( must admit, I’m a-feared of getting a big jolt ⚡️) and look for, and test the PCTR.
Dan

Dan with the power off, use a screwdriver to short the capacitor leads. Otherwise there is some risk of getting a jolt as you say. Some caps will have a shorting resistor across the cap leads to draw em down preventing that jolt. Either way getting knocked on your can when on the roof can be dangerous.

[Danjuan]

Originally Posted by Sparky19053

Dan with the power off, use a screwdriver to short the capacitor leads. Otherwise there is some risk of getting a jolt as you say. Some caps will have a shorting resistor across the cap leads to draw em down preventing that jolt. Either way getting knocked on your can when on the roof can be dangerous.

Thanks, Sparks’
Truly, I do respect being hard shocked, especially on a roof! I’m the guy with the rubber gloves, roof harness, and an aid car on standby in the driveway… !
My first discovery of capacitors was 55 years ago in Mr.Cook’s 8th grade physics class. Next, we soldered them to thumb tacks, charged, and stuck up from the bottom of our classmates plastic chairs… the only reason we arrived early for class, when they sat down and got ‘bit’, it was difficult not to give ourselves away with suppressed laughter !
I appreciate your response again, I’ll treat those capacitors with utmost respect !