A/C pump died. Is more GPH better?

[ohiohatteras]

My A/C pump died over the weekend. It's a TaylorMade PML500L rated at 490 GPH. Having trouble finding another new Taylormade pump. Found several March pumps with good reviews.

So....my question.....Is there any advantage to going with the next size up March pump that does over 600GPH? Will it help or hurt?

Thanks

 

[Sea Horse]

Just did a lot of research on this very subject. Answer is no it wont help to increase volume of water unless this was an issue which I doubt if it was working fine. March LC-3CP MD is what I would replace with. Found out they make the pumps for Cruise Air and they just place their sticker on the pump and charge twice the price. This pump I mentioned is rated at 510 gal and runs both my A/C units perfectly. Only issue to be careful of , is running it dry. It will heat up the plastic pump end and melt it locking the pump. It must be mounted below the water line and not be allowed to run dry. When I haul and relaunch I turn it on for a moment and look for it pumping out the side. If not I immediately turn it off take a hose and back prime by putting the hose under pressure in the exit thru hull and it starts right up. Flagship Marine in Florida was the best price I found @ $229.95 "Wet End" which is what they call the pump part can buy a rebuilding kit for about $80.00 far cry from Crusair at $275.00 for wet end.

 

[PeterK]

I just upgrade one of my AC raw water pumps. Output should be mated to the AC tonnage, i.e. 12K BTU per ton. I upgrade from 1000GPH magnetic drive to a 1250 GPH direct (shaft) with a metal wet end. If you are pumping warmer water, higher flow is desireable.

 

[captainwjm]

I just upgrade one of my AC raw water pumps. Output should be mated to the AC tonnage, i.e. 12K BTU per ton. I upgrade from 1000GPH magnetic drive to a 1250 GPH direct (shaft) with a metal wet end. If you are pumping warmer water, higher flow is desireable.

Agree with the higher flow in warm water; just had to do mine last week; went with the March pump over the original Oberdorfer. About 250 GPH more output on recommendation of the tech.

 

[PeterK]

We are on the Treasure Coast in Fl. and the original 1000s were marginal. We also had to increase the salon unit we replaced from 30K to 32L. Seemed a wise decision (as if I am accustomed to making wise decisions...) to upgrade.

 

[GJH]

An excellent source of expert advice and alternative products is Depco Pump in Clearwater. They carry about everything possible, including all the oem versions of the AC mfrs labeled pumps. Additionally they carry spare parts and rebuild kits. They also can likely rebuild your pump.

(727) 446-1656

I wouldn't shop anywhere else. And no, according to the really really good techs I've met, more GPH beyond original specs (who knows if the pump you found met them?) doesn't help, indeed can cause issues, since everything downstream is size and fitted accordingly.

 

[Boatsb]

Water will not absorb the head if it's running too fast. It has to be a match. Also in a gas boat a sealed pump is required. I'd be afraid of shopping for information on the internet. You get what you pay for in free advise.


What is the tonnage of the ac it services?

What is the inlet size?

What is the outlet size?

 

[ohiohatteras]

Any idea on what BTU's they put in a 1976 36C?
I have 2 units. One for the forward v-bunk and one for everything else......

 

[Boatsb]

Any idea on what BTU's they put in a 1976 36C?
I have 2 units. One for the forward v-bunk and one for everything else......

I could guess but thats not the way to do it.

I have a 16k and an 8K in my 41C

My buddy has a 16.5K and a 12k in his 34C

Another frind has 2 x 16K in his 42c

 

[jim rosenthal]

My 1971 36C has the original AC evaporators- one compressor unit has been changed. The V berth unit is about 7000 BTUs, the salon is 12,000 BTUs. The pump was replaced a few years ago. I think it is a March 500, but it's been long enough that I don't recall. I will be in there in a few days and will try to look at it and refresh my memory.