Air Conditioner question

I have three AC units on Ten Knots. The last couple of days have been really hot here in Ft Lauderdale and twice the compressor for the salon AC has cut off. If I let it sit 30 min or so it comes on and runs fine.

AC cools well and I have good water flow so, is it just getting too hot having to run 24/7 or is this an indication of an issue starting?

Have the coils ever been acid flushed?

They should be able to run 24/7 if you have good power to them. And they are operating correctly.

My wife and I were just going over AC THEORY. Could be the evaporator coils are gunked up. Next would be to ck impeller but, as I said water flow is good.

We will disconnect inlet and return lines at AC. Then using a small bildge pump and Home Depot bucket we plan to circulate an acid solution through the unit for X hours.

Any recipes for the solution? Muratic acid seems to be the go to but I ha e no idea to what strength to dilute it. And, how long u think we ought to let her go?

Many thanks! Still learning a lot. And ya know. I don't get flustered anymore. We just sit down and try and figure things out. It's fun!

I would use one of the commercial products made for this purpose: Rydline, Barnacle Buster, CLR, etc. Dilute it in accordance with the directions, 1:1 i think. Muriatic is too strong an acid for laymen's use. Also the commercial stuff has detergents that will help remove an oil that may be bound up with the scale.

David

djmarchand said:

I would use one of the commercial products made for this purpose: Rydline, Barnacle Buster, CLR, etc. Dilute it in accordance with the directions, 1:1 i think. Muriatic is too strong an acid for laymen's use. Also the commercial stuff has detergents that will help remove an oil that may be bound up with the scale.

David

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Thank you David. CLR sounds like a good choice. We will save the muratic for the Electra sans!

Could be the dock voltage gets so low , that another unit on the same power feed starts , and drops the voltage enouhj so yours cuts out.

They also run hotter with poor / low voltage and the unit might be shutting down as a safety feature?

Could be icing on the evaporator coils. Hot humid weather can cause it, or low freon can also cause it. Reverse cycle units will go into a defrost cycle periodically. Then they will blow hot air for a few minutes.

My new airs give pretty strict water temp limits for certain operations.....sounds weird and I haven't studied or tested them yet near extremes because of my location...what brand and year is yours?

Also I believe mine have a low voltage shutdown...any chance with the extreme heat in FL the power to the boat is getting low and the run to that ac unit is dropping it a tad more? Of course older and not all units have that feature.

Oooops....FF beat me to it....

Are they going off on high pressure or is the compressor going off on its overload. What is causing the system to shut down will help you find and correct the problem.

frgeorgeh said:

Thank you David. CLR sounds like a good choice. We will save the muratic for the Electra sans!

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Don't dilute the CLR. Or at least not by much. Barnacle Buster comes in two concentrations. One is ready to go out of the jug and the other you dilute 4 to 1 as I recall.

Got the 1-4 barnacle buster - ouch $72.00 a jug and a small bilge pump.

Cycled dilution through AC sysem 2 hours and then another 20 min of clean water. God the crud that came out.

AC running for over three hours and is cold. We will see how it goes and I will update.

Made a hell of a mess. Started pump with return hose on the carpet. Duh, what a dummy. I feel good though I did it all by myself!

This is what came out of the AC

djmarchand said:

I would use one of the commercial products made for this purpose: Rydline, Barnacle Buster, CLR, etc. Dilute it in accordance with the directions, 1:1 i think. Muriatic is too strong an acid for laymen's use. Also the commercial stuff has detergents that will help remove an oil that may be bound up with the scale.

David

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That would be Rydlyme.



-Chris

ranger42c said:

That would be Rydlyme.



-Chris

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Never heard of Rydlyme but, I am a newbie. That Barnical buster worked well but I almost passed out when she rung it up.

But, $75 to do three ACs is cheaper than calling the man. I have got to keep that in mind.

FF has a good point, everyone running the AC's at the dock can and will cause a voltage drop that can cause the units to overheat and also cut out due to low voltage.

If cleaning them doesn't help put a multimeter in one of your outlets and check voltage if the boat gauge is not operating.

AC line voltage at this writing is 116.3. That is middle afternoon, 3 ACs running and outside temp over 90 deg F.

That is fine. Not a low volt problem. .......Just checked mine is 115.8

Remember to do the flushing every 6 months if you are running in dirty water. Also shellfish will build up as they like moving water so a acid wash will do it. Here in the keys I put 1/2 of a chloride tab in my strainer every other month to kill the algae, shellfish growth . Don't forget the thru hull when cleaning the bottom.

Deckape said:

Remember to do the flushing every 6 months if you are running in dirty water. Also shellfish will build up as they like moving water so a acid wash will do it. Here in the keys I put 1/2 of a chloride tab in my strainer every other month to kill the algae, shellfish growth . Don't forget the thru hull when cleaning the bottom.

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Like a swimming pool tab? Great idea!

Interesting reading before you use swimming pool tabs. Some can cause problems. Maybe bromide tablets would be better than chlorine?

Chlorine tablets or, How I nearly killed me (and maybe "us"))))

BlueYonder said:

Interesting reading before you use swimming pool tabs. Some can cause problems. Maybe bromide tablets would be better than chlorine?



Chlorine tablets or, How I nearly killed me (and maybe "us"))))

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Thanks. Had no idea.

The Chlorine tab and piece of small piece of copper pipe really help but I also flush every 6 months

Small piece of copper and Bromine tabs every few months works well for me.

djmarchand said:

I would use one of the commercial products made for this purpose: Rydline, Barnacle Buster, CLR, etc. Dilute it in accordance with the directions, 1:1 i think. Muriatic is too strong an acid for laymen's use. Also the commercial stuff has detergents that will help remove an oil that may be bound up with the scale.

David

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Note: David is a frequent contributor to Boat Diesel.com and really knows his stuff. (He and Tony Athens keep a lot of folks (like me!) out of trouble & I take his writings to heart.) Thanks, David, for your contributions to TrawlerForum.