Do I need an accumulator tank?

question- just replaced my flo-jet pump 4406-143 and the paperwork says it "has a built in bypass valve eliminating the need for an accumulator tank" and not install it in a system with a tank as it would interfere with that valve. My system had a tank when I got the boat. Should I remove the tank? pump seems to work but a little slow to recover. old pump was a 4405-143

The accumulator should not hurt just added protection for the pipes, and reduces the number of times the pump comes on.

The slower recover might be the difference in PSI. What PSI is the new pump and what PSI was the old. I prefer the 30 as it easier on the tubing, and wastes less water.

psi is the same. just newer model of the same pump but I thought this bypass might be a new feature where the old pump may have actually required a tank and this one not?? I thought an accululator tank was to eliminate air from the lines...reducing chatter etc..

If you have room in your header tank for plenty of expansion the extra accumulator tank is unnecessary.

The main purpose of an accumulator tanks is to prevent quick on / off cycling of the pump. If you open a faucet just a little your pump will turn on as soon as the pressure in the line drops below a certain point but because the pump puts out a lot more water than your faucet is, the pump quickly builds the pressure back and shuts off. This can happen very fast, one second on, one second off. With an accumulator tank in the line this on/off cycle takes longer and you are less likely to damage the pump or pressure switch.

Newer designed pumps actually vary the speed of the pump to match the demand and don't need the accumulator tank. In fact it seems to confuse them.

It sounds like they are using the bypass valve to accomplish the same thing by feeding the excess water back into the intake side of the pump. I'd have to look at the pump design to figure out just what they are doing.

If you don't need the tank why not remove it and free up some space?

An accumulator needn't take much space.

Them pump engineers are pretty smart cookies. I'd heed their advice and lose the accumulator tank and let the pump function as designed.

I've been retrofitting many aging stationary facility plants lately and pump technology has come a long way in fifty years.

thanks..will bypass the tank and see what results

FWIW, I replaced my pump a couple of years ago, the new pump didn't require an accumulator tank and it seems to work well.

Damn you Mark, stop posting those pictures! You make me want to gut my boat and start over.
What's with the 6 position terminal strip for only two wires? Didn't WM have a 2 position strip? I know, cheap shot, but after looking at that beautiful layout I had to bitch about something!

Hopcar, I think that's for future expansion for power to up to 4 more pumps! I think it's great that Mark has a picture for everything...except pics of the inside of his beautiful Trinka.

FlyWright said:

...except pics of the inside of his beautiful Trinka.

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Al, remind me to dock on my starboard side later this month in Petaluma.

HopCar said:

Damn you Mark, stop posting those pictures! You make me want to gut my boat and start over.
What's with the 6 position terminal strip for only two wires? Didn't WM have a 2 position strip? I know, cheap shot, but after looking at that beautiful layout I had to bitch about something!

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Hey HopCar, I was aboard and toured the Coot Saturday afternoon in Stockton. Hard to believe with as many pictures Mark shares but the photo's do not do that boat justice! I could hardly believe the robust construction and attention to detail on it.

Problem is Perla gave my wife a comprehensive tour of the Coot and she fell in love with it. I suppose it wouldn't help telling my wife there are only 6 of them and none are currently for sale...

CPseudonym said:

Problem is Perla gave my wife a comprehensive tour of the Coot and she fell in love with it. I suppose it wouldn't help telling my wife there are only 6 of them and none are currently for sale...

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Craig, last I heard there were two more (#s 7 and 8) under construction. These are #s 5 and 6, however, pictured here:

Thanks for that Mark but I think we'll just enjoy Bliss for a while. Heading up this weekend to let Jennifer start to give it the ladies touch. She said after seeing your boat she's tired of my admittedly "Man Cave" decor choice for "our" boat.

HopCar said:

Damn you Mark, stop posting those pictures! You make me want to gut my boat and start over.
What's with the 6 position terminal strip for only two wires? Didn't WM have a 2 position strip? I know, cheap shot, but after looking at that beautiful layout I had to bitch about something!

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I know exactly what you mean Hopcar, whenever anyone posts engine room pics on here I cringe and feel very inferior...

HopCar said:

What's with the 6 position terminal strip for only two wires?

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More to the point, why are there exposed electrical connections?

Why on Earth install a terminal strip for that purpose in the first place?

RickB said:

More to the point, why are there exposed electrical connections?

Why on Earth install a terminal strip for that purpose in the first place?

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Makes for quicker, easier changing of the water pump if it fails...? It is only 12v after all.

An accumulator tank does more than soften the pumps work.

It also has to absorb the water expanded by heating hot water.

AS our boats have HW heaters of 6-10gal that mat heat from 65F to 190F (engine or noisemaker water coil) the pressure can get quite high.

I assume the non accum. pumps simply bleed the pressure back into the water source.

I do not know if thew accum. shown on Coots install has a bladder .

If not the unit must be emptied about monthly to replace the air absorbed by the water in it.
With no way to pressurize it one of the biggest advantages of an accumulator is lost.

The ability to match the tank and pump pressure and get 1-3 gal of water with out the pump operating.

Peter B said:

Makes for quicker, easier changing of the water pump if it fails...?

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As opposed to a nice washdown proof Deutz (for example) or other commonly available connector that doesn't expose live electrical terminals and look like it was installed by an apprentice gardener?

It is only 12v after all.

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Rick what's a Deutz? I googled it and only found a German tractor in the first couple of pages.

It's pretty common practice on boats to use terminal strips in protected areas like engine rooms. In exposed locations you mount them in boxes.

Terminal strips are a great way to connect two or more wires to one. Just use terminal block jumpers to make a common connection. You could use a buss bar for this but I think a terminal strip looks neater.

I always use terminal strips when I install bilge pumps. It makes changing them very easy.

He meant Deutsch.

RickB said:

More to the point, why are there exposed electrical connections?

Why on Earth install a terminal strip for that purpose in the first place?

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RickB is correct IMHO.

Why locate a terminal strip under water pumps and fittings? Most water pumps are on a separate breaker so they can be independently turned off, a terminal strip defeats that purpose if you hook other items up to it.

FF said:

An accumulator tank does more than soften the pumps work.

It also has to absorb the water expanded by heating hot water.

AS our boats have HW heaters of 6-10gal that mat heat from 65F to 190F (engine or noisemaker water coil) the pressure can get quite high.

I assume the non accum. pumps simply bleed the pressure back into the water source.

I do not know if thew accum. shown on Coots install has a bladder .

If not the unit must be emptied about monthly to replace the air absorbed by the water in it.
With no way to pressurize it one of the biggest advantages of an accumulator is lost.

The ability to match the tank and pump pressure and get 1-3 gal of water with out the pump operating.

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FF is right on in my book.

The terminal strip leading to the 24-volt water pump is not the only strip in the engine room. There is also one on the engine compartment forward wall:

"Most water pumps are on a separate breaker so they can be independently turned off, a terminal strip defeats that purpose if you hook other items up to it."

Are you maybe confusing a terminal strip with a buss bar? Terminal strips are used to join individual wires like you could do with crimp on butt connectors. The advantage is that if you need to remove a wire it doesn't need to be cut. It has no effect on how switches and circuit breakers work in the circuit.

HopCar said:

Are you maybe confusing a terminal strip with a buss bar?

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Buss or terminal strip, they should not have exposed terminals in an unprotected area such as shown in the photos.

There are protective covers available from most manufacturers and they should be used. Those covers protect the terminals from water or fuel spray and contact with "stuff" that might fall on them. They help keep the terminals clean to reduce corrosion.

Protecting terminals is simply good practice and replacing them after maintenance is good boatkeeping. An unprotected terminal might do more damage to your boat than lack of a fuel polishing system or the wake of a passing boat.

Covers certainly couldn't hurt. It's pretty common to cover buss bars but terminal strips usually are not covered. I guess because the design makes it difficult to accidently short between the terminals. Blue Sea Systems makes covers for all their buss bars but doesn't make covers for their terminal strips. Ancor doesn't make covers for their terminal strips either. Might be a good idea for them to make covers. It would give me something else to sell.

Anchor makes a Pin Terminal Strip that is less open than the common terminal strips but is is limited to about 25 amps.
Pin Terminal Blocks | Marinco

Sorry, but IMHO open terminals under water systems or worse yet adjacent to a pressurized fuel system is just plain wrong if not dangerous. In an industrial setting, in the case of flammables, it would be a shutdown and big fine when noted by the regulators. Ever read about coal mine disasters?

RickB and Sunchaser, how about some pictures of how wire connections are made on your boats?

I'm just saying that uncovered terminal strips are pretty common on boats and don't seem to cause any problems. I wonder what the ABYC has to say on the subject?