Recommissioning Air Conditioner

[mgmhead]

I am having a difficult time recommissioning my air conditioner. It worked fine last year but this season no cooling water is passing through the coils. I've checked the thru-hull (it works), the sea strainer is clean, took apart the pump and the impeller and assembly are clean. Removed the hose from the thru-hull discharge and back poured water until it filled the sea strainer. The pump sounds like its running but no water is circulated and then discharged. I've primed the system more than once. What am I missing?

If anyone had a constructive suggestion of what I should do next I'd appreciate the advice. I just can't think what the problem is, water supply is good, sea strainers clean, hoses and pump are unobstructed. I'm missing something simple I fear.

Any help?

Thanks...MGM

[negrini]

Did you check the pump running ? Open the pump exit, put hose somewhat higher to create back pressure and make sure it realy push water. Second I'd check if there is some obstruction inside coils (salt build-up ?) but since you were able to fill the system from exit back to the strainer, I'd think your pump is simply not working, or not puting pressure enough.

[mgmhead]

Thanks, I'll do that. I had checked the pump running and the discharge hose removed from the thru hull... no pressure. I'll check after the pump and before the coils. Guess it could be a faulty pump, even though it's only three years old.

Appreciate the response...MGM

[deniseO30]

From what I've gleaned about these little water pumps for onboard ac units, they do not have the ability to "lift or push" water very much at all. Is yours below the water line? Any restriction on either side would kill the flow. the first thing I would suggest is, find out if the heat exchanger has restricted flow. On larger water cooled ac units there is a water flow regulating valve that modulates according to the refrigerant pressure, thereby giving the ac a stable operating temperature. Possibly the HetEx is gunked up with slime?

[mgmhead]

Thanks for the thought Denise. If I find there is water pressure after the pump and before the heat exchanger...BINGO. I'll bet you've nailed it. Then all I need to do is de-slime the bugger.

Regards...MGM

[mgmhead]

Originally Posted by negrini

Did you check the pump running ? Open the pump exit, put hose somewhat higher to create back pressure and make sure it realy push water. Second I'd check if there is some obstruction inside coils (salt build-up ?) but since you were able to fill the system from exit back to the strainer, I'd think your pump is simply not working, or not puting pressure enough.

Thanks Negrini, your suggestion was the solution. With the pump discharge hose removed and the unit turned on there was barely a trickle of water moving out the end of the hose... and then, sploosh, a wad of semi liquid, nearly gelatinous, foul smelling goop spurged out and the water began to flow freely. Something had gotten through the sea strainer and pump but not through the discharge hose into the coil. Thankful to find it and happy it didn't get into the coil. The AC now works perfectly thanks to your tip.

Fair winds to you...MGM

[deniseO30]

Pssst.. it may also be in the coil since it has a long way to travel to the other side.

[mgmhead]

Originally Posted by deniseO30

Pssst.. it may also be in the coil since it has a long way to travel to the other side.

Yeah, I'm ignoring that possibility. I'm an if it ain't broke don't fix it guy...especially if it doesn't involve safety. I'm planning (hope?) that if it made it to the coil it will make it out of the coil. Afterall, the water flow is strong and it's leving a narrow tube and going into a large hose...it could happen.

This weekend is about flying the spinnaker and if the AC goes down I'll just turn on the fans.

But thanks for the whisper...MGM

[negrini]

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