Marine Air Condenser wont start.

[lelievre12]

I have a Marine Aire 12000BTU R22 condenser which pulls about 30 amps trying to start and then trips out. I have changed the starter and capacitor with a known good unit but still no joy. Refrigerant pressure is about 80PSI. I can see on the ships ammeter that this unit is pulling a lot of power trying to get going but it cant.

Are the compressors in these condensers known to lock up?

I'll change the whole condenser if I have to but wanted to check the forum first. They are $$$!

 

[Donna]

Will it kick on connected to shore power? I have a Marine Aire 16,000BTU aft that has a delay on it of about 2 minutes before it will start up.

 

[Bruce B]

Out of curiosity, what size breaker are you using?
I have seen breakers fail in this way. I have also run into shore power that is marginal leading to this condition. Can the unit run on generator power?
Curious...
Bruce

 

[Capt.Bill11]

I have a Marine Aire 12000BTU R22 condenser which pulls about 30 amps trying to start and then trips out. I have changed the starter and capacitor with a known good unit but still no joy. Refrigerant pressure is about 80PSI. I can see on the ships ammeter that this unit is pulling a lot of power trying to get going but it cant.

Are the compressors in these condensers known to lock up?

I'll change the whole condenser if I have to but wanted to check the forum first. They are $$$!

Yes they can lock up.

 

[lelievre12]

Out of curiosity, what size breaker are you using?
I have seen breakers fail in this way. I have also run into shore power that is marginal leading to this condition. Can the unit run on generator power?
Curious...
Bruce

I havent yet checked it on Generator power however we have 5 Marine Air condensers on the boat which are all working fine. Only 1 is refusing to start. We do only have 208V on the dock (not 220V) but for many years that has not been an issue with the condenser.

 

[Ski in NC]

If you have 208v on dock power, try it on your gennie. If no joy, the compressor could be pooped. Are you sure about the capacitor? Got the right Mfd rating, known good capacitor?

 

[DavidM]

If you still have the old capacitor, parallel it with the new one on the unit. If that won't start it, then the compressor is likely bad. If it will start, then remove the spare and try again. It may have just gotten stuck. Also whack the case with a rubber mallet to try to shake it loose as it tries to start.

David

 

[ranger58sb]

Last season, we had a problem with the Marine Air compressor not starting. Turned out, just fiddling with the wiring to the compressor fixed it.

There were 5 connections on the top of the compressor. IIRC, I just disconnected, cleaned, reconnected, all good.

The local Marine Air/Cruisair guys talked me through to that stage. Their next level of diagnostics would have been about the control board... but we didn't have to go there.

-Chris

 

[DavidM]

Chris has a good point- loose connections may be causing a voltage drop which is preventing starting. Easy to check: Put a voltmeter on the compressor terminals (probably accessible on a terminal strip where the wires from the compressor connect). Try starting and watch the voltage. It may drop to near 100V normally with the high starting current, but any lower and the connections are probably bad.

David

 

[ClChnge]

If the compressor is locked up you can try a "soft start kit"

https://www.amazon.com/SPP6-Capacitor-Increase-Starting-Torque/dp/B0002YTLFE

It connects across the existing capacitor and gives it a momentary boost of power at start up.

 

[ranger58sb]

I have a Marine Aire 12000BTU R22 condenser which pulls about 30 amps trying to start and then trips out.

Last season, we had a problem with the Marine Air compressor not starting. Turned out, just fiddling with the wiring to the compressor fixed it.

I should have specifically mentioned, our symptoms were much like what you're describing.

-Chris

 

[Martin J]

Marinaire delays while the cooling pump starts, are you pumping water? Clamp a ammeter on the pump and see what that's pulling. I had a similar problem and it was the March pump dying.
Are we talking Marinaire or marineair two different companies. I have Marinaire and they are exceptionally helpful. They will run you right thru the diagnostics.

 

[ranger58sb]

Are we talking Marinaire or marineair two different companies.

Ours that I mentioned is Marine Air (Airrrrrrrrr), Vector Compact model. I think now a Dometic company. I suspect current models are marketed as both Marine Air and Cruisair... possibly identical products except for labeling.

-Chris

 

[bayview]

does the breaker feel solid or soft. Depending on how long that 30A is pulling the breaker may be the problem especially at 208V. As above does it work on the genny????.

 

[High Wire]

Sounds like a bad cap but since you changed it, was it the same uF rating?
The reason it hums is it don't know the words, brrrrr-ump-bum-bump.

 

[Alaskan Sea-Duction]

Could just be a bad compressor........

 

[lelievre12]

Could just be a bad compressor........

Yep its a bad compressor. I looked up the Dometic diagnostic and its drawing 33 'locked rotor amps'. Thats what I am seeing on the ships ammeter before the unit trips out with its internal safety.

The good news is that replacement Tecumseh R22 compressors are cheap.

I got NEW Tecumseh Hermetic Reciprocating AC Compressor Replacement AK111JT-004 | eBay for $110.

I guess nobody wants R22 anymore..........

I'll report back once I have soldered it in.

 

[Alaskan Sea-Duction]

Yep its a bad compressor. I looked up the Dometic diagnostic and its drawing 33 'locked rotor amps'. Thats what I am seeing on the ships ammeter before the unit trips out with its internal safety.

The good news is that replacement Tecumseh R22 compressors are cheap.

I got NEW Tecumseh Hermetic Reciprocating AC Compressor Replacement AK111JT-004 | eBay for $110.

I guess nobody wants R22 anymore..........

I'll report back once I have soldered it in.

You may already know this, but you will need to put a vacuum on the system prior to adding refrigerant.

 

[kev_rm]

If the compressor is locked up you can try a "soft start kit"

https://www.amazon.com/SPP6-Capacitor-Increase-Starting-Torque/dp/B0002YTLFE

It connects across the existing capacitor and gives it a momentary boost of power at start up.

+1 on this, fixed three a/c units with same exact OP symptom with these... Caps go bad a lot more often than breakers or compressors.

EDIT: Also would mention looking at locked rotor specs vs. an instantaneous reading... not sure. The compressors in this size range I've troubleshot pull more like 50A instantaneous, but it should not blow the breaker.

 

[High Wire]

I'm adding this video for easy future reference on how to test the capacitor. Very simple test.

 

[lelievre12]

Could just be a bad compressor........

So I ordered another compressor can on eBay for $105.98.

Its a Tecumseh Hermetic Reciprocating AC Compressor AK111JT-004

These units are fitted to pretty much every refrigeration device in the USA and so they are reliable and cheap.

It's quite a job to pull out the Marineair condenser unit and cut out the compressor but is not that hard. There are 3 braze joints to make and the compressor is already filled with oil. Just use wet cloths around the braze area so as not to damage the paint in the area.

Once the new unit was brazed up I did a vacuum check (perfect) and the installed back in the boat. Recharge with gas and "hey presto", perfectly working unit. And very quiet as it is new.

So for half a days work and around $130 its nice to avoid having to spend $2,000 for a new condenser unit when only the compressor is dead.

So thanks to everyone for their help, but this compressor was toast and was never going to be revived. Now it is new again, I am very happy.