Cruisair 16k BTU

[whadapair]

Good Day,

I have a Cruisair 16k BTU unit that is giving me Trouble. The compressor runs for about 5 to 7 minutes and then shuts down. In that 5 t 7 minutes the air vent temperature gets to down 58 degrees and then cycles off.
What I have done-

Cleaned Strainer
Acid washed about 8 months ago
New Trigger switch 4 months ago ( the unit was continually running and fixed problem.

Water flow seems to be fine and other units are running.

Top of the compressor measures 139 degrees when I shot that temp.

Other unit is about 133 degrees.
My next step will be to acid wash again, I have to think it is cutting off because of heat not short of gas.

These are R22 units if that matters.

No I haven't put gauges on them yet. I have them but haven't had time to hook them up. And don't know how to read them LOL.....Yet


Any help would be Greatly Appreciated as always.

[a64pilot]

It could also be a clogged air filter/evaporator or if your fan speed is adjustable via a rheostat it may be too low a speed.
My old one had a rheostat fan speed control and if you ran it too low it would shut down

[bstreep]

You've eliminated just about everything you can without gauges. Go ahead and do the cleaning - scale can prevent heat transfer from to the water, causing it to overheat and shut down.



A decent set of Yellow Jacket gauges is always a good investment. You will quickly be able to tell if you are short or over on gas. However, if you have units that use R22, you might well be getting towards the end of their effective life. My personal opinion is that I'm not fond of Dometic products. Just not.

[whadapair]

thanks

I am going to give the coil a look today. Air flow seems to be fine but may be restricted a little.

Thanks

[GordMay]

Greetings and welcome aboard the CF, whadapair.

[Coolerking]

Unless you are trained in the use of refrigeration gauges, I would not recommend that you break the seals on it.
Your post is very vague, we need a model # and type of tstat.
If its a digital tstat then no fault codes?
Is this a split or self contained system?
If its a split system, and its faulting on high Psi, then you should be able to feel the discharge line when running in cool, its the 1/4" one that heads to the fan coil, it will be hot because you are not rejecting the heat into the ocean.
You say you had a trigger replaced because the unit was running all the time....the triggers are for the pump relay, each individual unit can call for the pump to run as need when the compressor starts, the pump only runs when a unit is being asked to cool, once setpoint is reached the compressor stops and so does the pump.
I am guessing that if the condensing unit ran when you powered it up on the breaker regardless of whether or not it was being asked to cool, it was a compressor triac that was replaced.
If the pump ran all the time, then its triac was shorted closed and when powered up it
would run all the time.
They even used to have a fan triac, which would, you guessed it, when shorted closed, run at max speed (on full line voltage) when powered up at the breaker.
The older units had an external replaceable triac for each compressor, and pump, the new systems have a triac on the 288A/B/C/D/U board itself and a separate pump output to the relay box.
You say that you have more than one unit.
Turn off all the others, and run the one you are having issue with, does the pump cycle on when cooling is being called for?
If so put your hands on the condenser, is it super hot?
If it is, then the water is finding the easiest path and bypassing the unit with the issue.
This can be proved by simply disconnecting the discharge side hose on the unit itself, connecting a hose (5/8") and putting it into a 5 gallon bucket to observe.
It needs about 4 gallons a minute
You can also compare the condenser temps to another one and see if the temps are close to being the same.
Have you checked the temp sensor location?
You can warm it up by hand and see if the unit runs longer.
Where is the boat located and what is ambient temp?
I do this for a living here on the west coast, get us the tstat type and look through the questions I posted and we can figure it out.

[whadapair]

Thanks for the Response

By no means am I a professional. I will have to get the model number but it is a split unit. It has a SMX II tsat and yes it had a Bad TRIAC not the trigger.

Its a 46' Bertram and has a 16K for the Salon, a 10K for the Guest and galley and a 7K for the master.

Yesterday I acid washed the unit and it appears to have much better water flow compared to he two other units. I also clean the evaporate and filter.

Same result, I drop the temperature on the tsat and the compressor comes on, Fan goes up to high and the air temperature coming out of the vent goes down to 59 degrees. It runs for about 5-7 minutes and then Compressor kicks off.

Compressor Temp is now about 131 degrees where it was about 140 before I acid washed. The compressor to the touch still feels hotter then the other units.
The boat is Ft laud. water temp is about 75 degrees now.


One question is it possible even know I acid washed the system I have a restriction in the tube going through the compressor? If so, how do I clear that?


Still looking for my gauges so I haven't got readings. But correct me if I am wrong I would not get any cooling if it was low on gas????


Thanks for you advice.

[Coolerking]

My guess is its an WFAH, or R/F series.
Its not showing a fault when it shuts down??
LO-PS
HI-PS
LO-AC
You say the compressor is hot, do you mean the condenser coil?
If you have one pump, feeding all the units, the only way to be sure the condenser is clear is to remove the hoses on it and check.
If you have a restriction in either the feed hose to it, or the overboard run to the sea, then, like I said, the water will bypass it for an easier route, the water coming out of the boat will look the same, its just not going thru the unit in question.
Have you found the manual for that system and read it? They are easily found online. Its # L-2086
If the system starts and runs that means that the internal refrigerant pressure is above the lo ps switch cutout when sitting idle at ambient.
If it was a little low on refrigerant charge, it could, during cooling, pull the lo side under the switches cutout point and turn off, but it should show a fault, which leads me to this next point...
How do you know what the air temp is coming out of the grill, not that it matters, because it will change as the unit works on the air in the space being cooled.
Are you using a thermometer?
Have you located the temp sensor? It will be in the return air path someplace.
Make sure its not touching the coils or anything else.
What does it read the inside temp as? And is this correct?
You realize that the SMX display show 3 different temps? inside, outside and setpoint?
It could be reading the room temp wrong, thinking its colder than it really is and thus it turns off.

If you set it to heat does it run longer?
Keep us posted.

[whadapair]

Didn't have a bunch of time today.
Yes it is a WFAH-6
The SMXii shows no codes. I reset it and it seems to be operating normally
I shot the temperature of the Compressor with a IR gun and the temp on the top was 150 degrees when it shut down.
I have to discount water flow at this time. I acid washed the unit and the acid circulate freely.
The condenser coil is not hot at all.
Side by side compared to the 10K btu unit that is working perfect.
The manifold on the suction side of the 10k is real cold but on the 16k its just cool.
on the discharge side they both are about the same hot.

I set the tsat for 68 and the unit ran for about 12 minutes and drop the temp in the salon to 74 before compressor cut out. It took about 10 minutes before it came back on then shut down after only 5 minutes. I shot evaporate with a IR gun and it was at 58 degrees.

I ran out of time today.

Thanks

[Coolerking]

WFAH16k shows no lo ps switch installed in the electrical drawing I have, which is from the factory tech manual, but you might confirm that.
It will look exactly like the hi ps switch but it will be on the lo pressure side of the refrigerant piping circuit on the condensing unit.
2 wires on each one wired in series.
It also shows a mechanical control, did they retro yours to a SMXII?

If you don't have the lo ps switch, you most likely have an electrical, relating to the early cycling off, either the compressor has begun to fail and is cutting out on overload, the start parts may need looking at.
also have you checked that all the wires are clean and tight?
You need to get a clamp on amp meter and put it on the input L1 wire and see if the amps during cool match the listed amps, I show 14 @115vac and 6.7@230vac.

If you have R-22 and understand how to use the base valves and service ports, how to properly purge the hoses of ANY air before opening the system to the gauges, you can also go that route, but no lo ps switch means it's most likely shutting off for some other reason.

[rbyham]

I was reading this thread the other day as I was researching my problems with what I think is the same F series 16k Cruisair. I have this as orig equipment on a 1995 Catalina 36 MKII. She runs variously for 10 - 20 minutes before shutting down stays off about 20 minutes and goes through same cycle again. We are very hot these days in Charleston and typically inside temp of boat is in mid 90s when I turn it on. Water temp is about 86 but will soon be in low 90s :-(

This is all on my boat and at my marina which I say because last week we cruised and overnighted at a diff marina and the crazy thing ran from 8PM until morning and we woke to a 73 degree boat... Wierd.

Before I call in a pro which I am decidedly NOT I was wondering if there was any resolution to the OP of this thread and/or any further thought from folks on directions? Thanks.

[rbyham]

In case it helps here is some more info Model: FX16 Stock: 4616300 Serial: A95AU62