advice about AC problems

[SeaSon]

Assuming compressor doesnt try to run: As you don't have external relays on this system, you can first check for power to the compressor with your voltmeter on the terminal strip, then confirm by moving it's hot lead to the fan power on the terminal strip. If it runs, then logic board or pressure switches. If not than compressor or connections. I'd vote for connections as a faulty compressor usually runs noisy.

Forget about dirt on the coils for now. That's just wishful thinking.

[Jolly Roger]

Well I’ve finally managed to pull the AC unit out of it’s cubby hole, and dismantle it as far as I dare.
I first tested all the grounds and they are good, not corroded at all.
I then removed the high pressure switch on the circuit board (there is no low switch and the blue wire goes nowhere). I also tested the wires through to the actual switch. I then did an Ohms test on the two terminals on the switch and at first it read 40 Ohms! I understand it should read zero. Since it is screwed into the gas lines I can’t remove it. So I tapped it with a hammer and then it read 1 Ohm, but it will not go to zero.
Am I right in thinking if this switch is closed, the compressor will not come on?
Can I start the unit with the switch disconnected to see if the compressor comes on?
The connections to the compressor are all good, tight and clean. The compressor earth is good. I have not done any tests on the compressor capacitor, which I assume is the big round thing on the circuit board? I’m not sure how to test it—don’t want to electrocute myself.
The AC unit has not been switched on now for four days.
You can see from the label it is charged with R438 Is this still available?
Further advice (please keep it simple—I’m British), will be highly appreciated.
JR

[transmitterdan]

Have you tried sending them an email?

pompanette@pompanette.com

[Jolly Roger]

Yes I've talked to them and they are not helpful. Say I have to get an AC tech, but they can't recommend one in my area. Pretty useless really.
And under no circumstances must I take the top of the control box.
They didn't say anything about taking the unit to pieces though.
The only person I have found who will come out to the boat can't come for two weeks.
I have to do it myself, as usual.

[pesarsten]

R438 is also called ISCEON M099 , it is an r22 drop in replacement. Current cost is about $20 per lb.

It sounds like the HP switch is failed. The 1 ohm is fine but 40 ohms and dropped to 1 when you whacked it indicates a failure. When the switch is open it prevents the compressor from running. It opens when the refrigerant pressure gets too high and resets itself when the pressure drops. They usually fail after they have been cycling for a while, possibly due to low water flow.

Most are installed by screwing on to a Schrader valve which allows removal and replacement without pulling the refrigerant. If yours is brazed in to the line, you can get adapter fittings which allow installation on the HP pressure tap fitting. The switch will have a pressure printed on it usually in the form of open pressure / reset pressure , like 350 / 105. It's a less than $10 part. You may want to bring the unit to an HVAC guy to switch them though, there is a technique and screwing it up results in an expensive PSSSSSSSSSSSSSSS sound when you crack the refrigerant line.

[Jolly Roger]

Thanks Pesarsten,
It's screwed into the line, but I'm not sure with a schrader valve. I'll phone the makers and ask. I'm used to those valves.
Here's what it says on the switch.
YK - 01H
000-2.72R2.03X
Open 2.72 Mp3
Close 2.03 Mp3

If the switch is open to run the compressor, can I disconnect it to see if the compressor fires up?
JR.

[pesarsten]

The switch has to be closed to run the compressor. As in shorted.

It starts out closed at normal pressure and opens at extreme pressure to protect the system. Then closes when the pressure normalizes. You can test by shorting the wires together.

[pesarsten]

That switch opens at 395 psi and closes at 295 psi
Locally available cheap!

[Jolly Roger]

It was a struggle to remove the unit, but we managed to get it out and I made some of the tests recommended by everyone.
I Ohms tested the compressor: Start to common 2 Ohms. Run to common 4 Ohms and all connections are good.
When I reassembled everything the compressor started up, but it was not blowing cold air.
I did a test with a gage I have to measure the PSI on the low pressure side. 70psi static and dropping to 10psi when the compressor kicked in. I understand that means pretty much a loss of freon?
Perhaps that has been the problem all along?

[SeaSon]

Jumping compressor hot to the fan hot will by pass all logic and safety circuits, as a test. You can do that at your logic board easily.

The low pressure switch would be strapped to the side of the foam covered piping, in an area where the foam is cut. My LP switch bypassed by cutting it's lead, so it was normally OPEN, and was in series with my HP switch, leading me to believe mine would be normally open also.

BTW, if you replace the unit, Ocean Breeze has trouble shot both my old systems on the phone, and helped solve my problems. Looks very similar to what you have with a different control system.

[Maker42]

Originally Posted by Jolly Roger

I have not done any tests on the compressor capacitor, which I assume is the big round thing on the circuit board? I’m not sure how to test it—don’t want to electrocute myself.

The capacitor is the big silver cylinder mounted next to the circuit board. If your compressor turns on, it's probably good. When they go bad, you can usually see that the top of it pops up like a soda can left in the freezer. Yours doesn't look that way.
So with 2 indications that your capacitor is OK, I recommend focusing on other causes.
If you think the refrigerant is low, be cautious trying to run it, because it also acts as a lubricant to the compressor. Running low on refrigerant is like running an engine low on oil.

[Jolly Roger]

I won't do anything more until I find someone who has R438a (MO99) who can fill it up—at a reasonable rate.
I found a local guy, who said he lived ten minutes away, but still wanted $90 call out fee, $90 per hour, and $75 for 1lb of gas. The system takes 16 oz.
A 25lb bottle of gas can be bought for $250. That’s $10 a lb, so when I asked him how he justified $90 for coming ten minutes and $75 for 1lb of gas, his reply was, “That’s a going rate.” It ain’t the going rate for me, I said!
It’s not that I can’t afford it, I just don’t like being ripped off whenever I mention I have a 50 foot schooner.
I’ll get there, and be a lot more knowledgeable for it.
I’ll keep you all posted.
JR

[dtrue]

Jolly, Sry for the delay in responding back . I have been down at coast as well for a few days. I got your schematic you sent me but can't seem to locate it now.

All I can say is wow.... I wrote you a book this morning, submitted it and went to login and lost the writing.
So, By now you have gone for visual on youtube and /or google.
Capacitor discharge and charge.
Ohming out compressor.
Troubleshooting compressor, etc.

Pics show well and cleaning is in order. Jolly, Chase the power to part easily identified. check and use common sense if power line charge breaks here what is happening.

"Adler Borbour" and "Pompanette" brands popular on boats may not be online for exact but all Pot compressors check out the same.
Matter of fact most pots are the same this size only vary by mounting order and tubing placement, voltage and capacities. Its all in the plate on compressor. No need to order from out of country or from manufacturer of unit. Compressor could be only couple hundred dollrs by itself.

Vac down and charge.... isnt so easy since you don't know how much is in unit as is. Vac lines down before hooking up to quick connects if possible.

Here again is a when a professional serv needed to top off refrigerant but after some savings on compressor and install maybe it wont be to expensive. But it needs to be right and it will have to pump for a while to get that reading on gauges.

What I did what to let you kinda be privvy too. You can go to refrigeration like restaurant service commercial mostly and get help.

Or freezer -refridge repair man used appliance shop guy in town, these guys are super and cheap on bench repair when it counts.

I use Johnstone supply for a lot of my parts and some compressors, quick delivery. Phone order service top shelf. also Custom supply these are both in Texas

#SPP6 "Super Boost" hard start kit

Good luck troubleshooting.. dtrue

[Jolly Roger]

Like I said before: I have a gage I can screw into the input port which measures psi. With the unit off it reads 70 psi and the moment I switch the thing on the compressor kicks in and the pressure drops to 10 psi.
An AC technician just said, “You need freon.”
The manufacturers don’t do any factory or outside service, (something I would draw to the attention of anybody about to consider a Pompanette Air unit). They can’t recommend anyone in my area either, in other words they have been useless. They did tell me however, that I must not refill the unit with R22, even if we vacuum the thing first, and I must use R438a, which is one of the gasses which took the place of R22 and what was installed in my unit.
So I’m trying to find someone who has R438a and can either come to the boat, or I can take the unit to them. So far, no luck.

[dtrue]

Jolly so you did have a low pressure switch opening circuit. If you can find a bottle of r-22 charge it to 69psig on suction side and your good.
dtrue