Variable Speed Pumps

[freightdog]

Anyone had much luck with using just a variable speed fresh water pump, in lieu of a pump and accumulator combination? My 25 year old fresh water pump went out on me the other day and I need to replace it.

As well, the new accumulators that West Marine sells are plastic. Any problems with plastic versus the metal ones? Thanks.

[swagman]

Can confirm the variable speed pumps work just fine.
And the only issue with plastic accumulators is they don't rust out with time!
JOHN

[Pblais]

It depends on the length of the water line and how many points of use you have to size the accumulator tank properly. For a medium sail boat with a galley and one head and maybe a cockpit shower one of the small Jabsco plastic tanks is fine. I use a belt driven single speed pump. If I open one tap fully it will cycle 7 seconds on and then the same off with even pressure. This reduces the pump operation to half. The pump has a pressure switch built in to shut off at the desired pressure. Without the tank it would need to run constantly.

They do make pumps that are supposed to eliminate the need for a tank but I'm not sure they will handle all types of situations. They don't use a variable speed but use multiple chambers. They really can't do that with variable speed.

Not all pumps systems are as noisy. The larger tank might allow water use at night without activation of the pump. Even the small tank we have can get a glass of water without the pump going on. Our pump can pressurize the tank and deliver water to one tap. With two or more the pumps runs continuously and there is a pressure drop. A 50 ft trawler with 3 heads and such just can't get by with a small pump. The pressure loss in the pipe eventually gets you.

[David M]

I have a metal pressure reservoir which has rust on the outside. I kind of wish it had been plastic when I bought it.

[mobetah]

We deep sixed the old diaphragm pump and accumulator tank onbaord Mobetah and installed a Jabsco sensor max pump for the fresh water system six or seven years ago. We have had absolutely NO truouble with it! We love it and will replace it with another one just like it if ever dies!

Bill A.

[Marinheiro]

Is there any experience out there of how the Shurflo version of the variable speed pump has performed in service?

[Whimsical]

Second hand info but the chandler I buy a lot off has nothing but bad to say about them. He has had several of them go to fullspeed and refuse to turn off. Seems to be an issue of electrical noise sending the control circuit, microprocessor?, stupid. He refused to sell them any longer.

Mike