Water Pump Accumulator

Lance Jones · December 21, 2009, 07:23:25 AM

Has anyone ever installed a water pump accumulator? A fellow live aboard did this with his and it says it made a big difference in the cycling of the water pump.

sedelange · December 21, 2009, 11:51:31 AM

I replaced my pump with a Jabsco Ultramax that included the accumulator. Works great as the pump only cycles when the faucets are open. Pressure is good. Only problem I have is the 1/2" supply lines are too small for the pump and I can get cavitation. Supply hoses are to be replaced with 3/4" soon.

Ron Hill · December 21, 2009, 02:27:34 PM

Lance : If you have a Flowjet pump you really don't need an accumulator.

Ken Juul · December 22, 2009, 04:12:14 AM

If your fresh water pump is cycling without the faucet being on then you have a slow leak somewhere. With everything tight, no leaks, the system should hold pressure for hours without cycling. Murphy ensures it is always the last, hardest to reach clamp that is the problem. Start there and work to the easy ones.

Lance Jones · December 22, 2009, 06:55:28 AM

Ken,
You're probably right. I think it is at the sink faucet. Any easy way of tightening those connections way up top?

Jim Hardesty · December 22, 2009, 08:01:20 AM

Lance,
I did on my previous boat, it did cut reduce the pump starts. On my MKll I don't think that it would be worth the effort or space. My live aboard friend put in a standard plumbing accumulator and large pump doesn't cycle much at all.
If you are at a marina, why not hook up to the shore pressure water? Thats what some of the live aboard's do here.
Jim

Mike and Joanne Stimmler · December 22, 2009, 08:16:08 AM

Just in case you check for leaks and don't find anything, it could be the pressure switch in the pump.
After doing some plumbing changes a few years ago, I was having problems with the pump cycling on and off every few minutes and I was sure there was a leak somewhere but found none. Coincidentally, the pump proved to be the culprit. The pump looked to be the original so I decided to replace it with a new quieter one.

Mike

Stu Jackson · December 22, 2009, 08:49:52 AM

You have four choices:

1. Stay with the pump you have, find the leaks if it's cycling when it shouldn't.

2. If the pump or the diaphragm are broken, replace with parts or the same type of pump.

3. Add an accumulator to 1 or 2. It doesn't solve the (pump or diaphragm) problem(s) you now have, it is only for significantly reducing the older style pump's normal cycling by adding a "bladder" of water and air to minimize cycling of a simple pump.

4. Buy a newer style pump with essentially like having a built-in accumulator which is done with variable speed pumps; they do NOT need accumulators.

That's for a pumped system. Of course, direct connections are another different option, but make sure you NEVER leave your boat with the water left on, NEVER.

A few years ago they started making pumps with built-in accumulators, then they may have stopped that and now offer variable speed pumps. Both could still be available, I don't have the catalog in front of me now.

I've been reviewing this for years now for Aquavite, but my original pump just keeps on a workin'!

By the time you price an accumulator, you'll most likely find it better to replace it with a new style pump.

Some folks who are handy made their own accumulators with large diameter PVC pipe, a bicycle air tube fitting on top and hose barbs on the bottom.

I've often asked myself "Why?" Absolute elimination of water pump noise is more necessary for live aboards, but even when we're cruising I don't see the need for it, unless someone's still sleeping when someone else is taking a shower, in which case the newer pumps will work, although they are inherently quieter 'cuz they're newer.

Ken Juul · December 22, 2009, 08:59:39 AM

I find a socket and various extensions/swivels works much better than a screwdriver for tightening clamps. Just don't over torque and crush the plastic fitting. I think I had to unbolt the water heater and slid it out of the way to get to the galley sink and hot water connections between the HW heater and the bulkhead.

Lance Jones · December 22, 2009, 09:47:59 AM

I have direct access below the faucet after installing my hatch. It is just real narrow up behind the sink. Thanks so much for the great answers!!!!!

Lance's wiki is here: http://www.c34.org/wiki/index.php?title=Sink_Access [Stu]

David Urscheler · December 22, 2009, 01:31:17 PM

My pump was cycling a while back and I was going crazy looking for a leak. After tearing the boat apart to check all the water tank fittings, I found the culprit. It was the dockside water connection under the propane locker! I tried tightening the clamps and the fitting itself to no avail. Since we don't use dockside water, I cut the hose off, clamped in a PVC plug and problem solved.