Air Conditioning Pump
- Thread starter dwarren
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boatcomfort
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Depends on model, size.I have some refurbished pumps. But need to know the size.
"I think the pump actually went. It fires up and "whines" but no real water flow. No blockage either. Any idea on fixing/replacements?"
Before you move on please consider a couple of other possibilities from this description....
1. The pump lost prime and is just spinning in air, make sure you have the lines primed and no air in the pump as that is the easiest solution.
2. Some of the larger pumps utilize a magnetic coupling between the electric motor and the impeller housing with the pump vanes. Take the impeller cover off and make sure that there is not something jammed in the impeller area or the bearings keeping the magnetic coupling from working.
I have seen both issues with the above description each of which is a reasonably quick fix.
Hope this helps
Before you move on please consider a couple of other possibilities from this description....
1. The pump lost prime and is just spinning in air, make sure you have the lines primed and no air in the pump as that is the easiest solution.
2. Some of the larger pumps utilize a magnetic coupling between the electric motor and the impeller housing with the pump vanes. Take the impeller cover off and make sure that there is not something jammed in the impeller area or the bearings keeping the magnetic coupling from working.
I have seen both issues with the above description each of which is a reasonably quick fix.
Hope this helps
- Joined
- Sep 16, 2003
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What kind of pump? Brand, size, etc
How do you know there is no blockage? It could be something in the thruhull or in the hose leading to the pump. There could also be some shells or debris in the line from the pump to the AC unit
Start at the pump. Close the seacock, Pull the hose on the discharge side of th pump then open th sea cock. You should have water coming out of th pump even she not running. If not, the problem is before the pump.
If you have water flowing, reconnect the hose and disconnect at the AC unit, out hose in a bucket and turn it on, check for flow.
If you have flow, then th problem counted be inside th AC coils. Undo the hoses on both end and blow thru th coils. You should be able to blow thru without too much effort.
Basically you want to go one step at a time.
Another common issue is a plastic bag in the intake. Outside th hull. Problem is that water will flow in with the pump off but with suction the bag gets sucked in tight. If you have water flowing out of the pump when it s off but not when turned on, that s often the problem.
How do you know there is no blockage? It could be something in the thruhull or in the hose leading to the pump. There could also be some shells or debris in the line from the pump to the AC unit
Start at the pump. Close the seacock, Pull the hose on the discharge side of th pump then open th sea cock. You should have water coming out of th pump even she not running. If not, the problem is before the pump.
If you have water flowing, reconnect the hose and disconnect at the AC unit, out hose in a bucket and turn it on, check for flow.
If you have flow, then th problem counted be inside th AC coils. Undo the hoses on both end and blow thru th coils. You should be able to blow thru without too much effort.
Basically you want to go one step at a time.
Another common issue is a plastic bag in the intake. Outside th hull. Problem is that water will flow in with the pump off but with suction the bag gets sucked in tight. If you have water flowing out of the pump when it s off but not when turned on, that s often the problem.
- Joined
- Sep 18, 2007
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The do sell rebuild kits. Just did mine this past fall since I kept losing prime. Works fine now, it was a March Pump.
This company has a huge selection and rebuild kits.
http://www.depcopump.com/catalogs.php
This company has a huge selection and rebuild kits.
http://www.depcopump.com/catalogs.php
Capt. Bill1
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Of course if it's a Cal pump, just throw it in n the trash and replace it with a March. 
- Joined
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My pump did this as it lost prime. Try getting water in there with garden hose
- Joined
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I ve had a couple of broken impellers on March pumps over the year, usually the piece jams in outlet and makes a clicking noise. The nice thing about March is that you can pull th cover and replace the impeller without having to remove the whole pump or even undo th hoses.
If installed properly, ac pumps should not loose prime. If they do it means you have a high or low point between thre strainer and the pump. Better fix that than dealing with loss of prime forever. By now you d think builders would know how to install pumps!
If installed properly, ac pumps should not loose prime. If they do it means you have a high or low point between thre strainer and the pump. Better fix that than dealing with loss of prime forever. By now you d think builders would know how to install pumps!
Capt. Bill1
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Or air conditioners, plumbing, wiring, electronics, refrigeration, hardware, lights, A/V equipment, engines, gensets, etc., etc., etc..........
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They don't lose prime in the water, but if you haul out and have no water and try to prime by pouring water into the strainer with seacock closed, it won't prime. It needs pressure to prime. I learned this the hard way when winterizing my A/C.
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- Sep 16, 2003
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So what happens when you clean the strainer?
My point is that if the pump is below waterline, and if it is installed close to the strainer with the hose running straight uphill, it will reprime after a haul out or a strainer cleanup.
I relearned this the first time I hauled out my old maxum 37, back in 99. Launched back and no flow. Turned out they installed the pump on the other side of a stringer with the hose going over. Took me 30' to relocate it, no more issues,
My point is that if the pump is below waterline, and if it is installed close to the strainer with the hose running straight uphill, it will reprime after a haul out or a strainer cleanup.
I relearned this the first time I hauled out my old maxum 37, back in 99. Launched back and no flow. Turned out they installed the pump on the other side of a stringer with the hose going over. Took me 30' to relocate it, no more issues,
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When you clean strainer in the water, you close the seacock.
As soon as you open it back up, water pressure from the water shoots up and fills up the strainer and hose.
If you are on land, then there is no pressure unless you have garden hose hooked up or gravity feed into strainer.
Just pouring water or pink into a empty strainer will never prime it since there is no pressure.
As soon as you open it back up, water pressure from the water shoots up and fills up the strainer and hose.
If you are on land, then there is no pressure unless you have garden hose hooked up or gravity feed into strainer.
Just pouring water or pink into a empty strainer will never prime it since there is no pressure.
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- Sep 16, 2003
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Ok... But there is no diffence between opening the seacock in the water after the pump lost prime because you opened the strainer versus launching the boat.
You have the same pressure of water coming up the hose from th SC to the strainer and up to the pump until it reaches the waterline.
The problem is when you have a high point in the hose... You will have an air bubble which will not always get sucked thru, in that case, yes you need pressure to eliminate it. The cause is still a lousy install.
You have the same pressure of water coming up the hose from th SC to the strainer and up to the pump until it reaches the waterline.
The problem is when you have a high point in the hose... You will have an air bubble which will not always get sucked thru, in that case, yes you need pressure to eliminate it. The cause is still a lousy install.
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Yeah Op doesn't say if he is in water or out. He is in NY so I assume out.
If he is out and he lost prime he won't get back unless he gets pressure in there.
If he is out and he lost prime he won't get back unless he gets pressure in there.
Sorry I'm so late to the game on my own post. I'm planning on pulling the unit apart (snow blocking my way to boat currently). There was no blockage from seacock to pump and I verified no blockage throughout system (good flow with hose attached bypassing pump).
Started slowing down during the summer and I thought it was build up on strainer but strainer was clear....
I'll pull unit info. Thanks for all the help.
Started slowing down during the summer and I thought it was build up on strainer but strainer was clear....
I'll pull unit info. Thanks for all the help.
These pumps are not self priming. I would try priming it before you go crazy. I've found the easiest way to prime mine when it goes back in the water each year is to (with the seacock open) briefly disconnect the hose from the discharge side of the pump, and as soon as water starts to come through the pump (a few seconds), I shove the hose back on the fitting, tighten the clamp, and I'm good to go for the rest of the season.