Variable speed pump or pump and accumulator?

[sailingdolphin]

The jabsco guy recommended the later because he said the VS cycles on and off. It wakes you up.

Looking for pros and cons.

[Stu Jackson]

Doug, it'll only wake you up if there's a leak in the plumbing.  Or if you don't turn it off at night - why not?

The choices are thee:

1.  Regular pump without accumulator
2.  Regular pump with accumulator - which serves to reduce the pump run time each time you turn on the faucets, but the pump will still run to pump the system up to pressure when all is said and done, because the accumulator doesn't MAKE pressure, it only kinda buffers the highs and lows
3.  VS pump - generally quieter because it only runs to make up the pressure lost when there's small amount of flow compared to the regular pump which cycles more loudly.

I've heard various debates about the merits of each, until the cows come home!  

Regular is better 'cuz you hear the pump run and know if there's a leak (just happened to us!).

Accumulator is better 'cuz the pump doesn't run so often.

VS is better 'cuz you hear a lot less.

It's simple:  Your boat, your choice.  There is no BEST.  It's a boat: there are OPTIONS.

Good luck.

PS - One other thing - Jabsco pumps do not have a great reputation.  I'd buy a Shurflo.
http://c34.org/bbs/index.php/topic,5990.0.html

[mainesail]

Standard pump and accumulator HANDS DOWN. Pretty fool proof. I have fixed / replaced more VSD pumps since they came out than I ever have of the standard pumps. Was just on a beautiful J-42 last week and the customer is on his third VSD pump in two years. He took out the beautiful SS accumulator and standard pump to gain storage for, of all things, paper towels......

I re-installed his original 8 year old system last week and it performs as it should. The third VSD went straight into the dumpster.. Until they become significantly more reliable then I would urge the standard pump and a simple accumulator.

[lazybone]

Or,  no accumulator and you shut the pump off when you go to sleep?

[Ron Hill]

Guys : If you read the literature on different pumps; you'll find that some recommend NO accumulator tank!!

A thought

[sailingdolphin]

Ron, I think the VS pumps say no accumulator.

I hear from so many sources that the VS pumps are unreliable.  Our local West Marine says they get a lot of shurflo VS pump returns.  The Jabsco par max plus has good reviews on west Marine. The shurflo ratings on West Marine are not very good.

I currently have a belt drive 3.3 GPM 40psi 6 amp.  It doesn't have enough pressure, its really loud,and variable flo. 

So I am looking to switch to a 5 GPM, 60 psi, 12 amp Jabsco par max plus and accumulator tank.
Any thoughts? This is on a Cat 42 Mark II so there are two heads and 3 sinks.

[Ron Hill]

Doug : Go to the Defender catalogue page 100 and look at the FlowJet water pumps.  Model 04305500A will pump 3.3 gpm at 35psi and costs $177, no accumulator tank necessary.  This is all you really need!!

It has quick connect/disconnect fittings which is great for winterization.

A thought

[DarthOccam]

PS - One other thing - Jabsco pumps do not have a great reputation.  I'd buy a Shurflo.
http://c34.org/bbs/index.php/topic,5990.0.html

Mainesail sees more of these than do I, but here is my experience:  I had two Jabscon VS pumps fail in the first year we had the boat. The Shurflow has made it twice that  so far. 

Michael

[Indian Falls]

 I put a 24" long  3" diameter pvc pipe, capped both ends, with a 1/2'' hose barb, right alongside the starboard holding tank for an accumulator.  It's nice to trickle the faucet and not have the pump run  but if I could do over I would make that as long as would fit there, and almost four feet would do it.

[mainesail]

An accumulator tank has a rubber diaphragm in it. Pressurized air on one side water on the other. It keeps steady pressure on the system and reduces pump cycling. Without a diaphragm and the air pressure on the bladder/diaphragm you just have a big diameter pipe..

[yonar]

Another source
http://www.marinesupplydock.com/Flojet-Marine-Pump-12v-Quad-12v-DC-Water-System-Pump-Model-04305500A.htm

[yonar]

Lower price
http://www.hodgesmarine.com/Flojet-Quad-Dc-Water-System-Pump-12v-p/flj04305500a.htm?click=18

[Indian Falls]

The "pipe accumulator" without a bladder will work for a long time before it becomes water logged. 
So far all summer it's been working just fine.
It will and should have some water in it as the pump compresses the air by pushing water in. 
Over time this air will be absorbed and the tank will become waterlogged, and need to be drained.
On mine the 1/2 hose barb is at the lowest point,  only water should leave the accumulator tank as the air expands pushing the water out the faucet.  I had the same thing in my camper and it worked fine.  The larger the volume of air the more time before the pump runs.

Another benefit of a diaphram tank: it matters not where you orientate your connection. 

Hey it's your money! Mine is almost free.

I just had a thought: when my water tanks run out the pump pushes lots of air into the system. Turning on the faucet then ejects water from the "Pipe accumulator" where the pump will fill it again with air.   That could be why I have gone 3 months without a waterlogged pipe accumulator.    No matter... it works fine, just wish it was bigger.