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I have a Jabsco that is barely adequate. I want to replace it, but can't find a definitive source for rating freshwater pumps. I like FLOW and PSI. Not very concerned about amperage usage.
Anyone have experience with a particularly good pump or can otherwise point me towards a reference.
Shurflo no longer makes variable speed pumps and if you have an older working one, you are very lucky. We went through 5 of them (under warranty) before they dropped the line.
This works very well with lots of flow and high pressure (and not being specific "marine" pump, it is half the price). While it is variable speed, we find it still cycles at very low flow.
Shurflo no longer makes variable speed pumps and if you have an older working one, you are very lucky. We went through 5 of them (under warranty) before they dropped the line....
Forgot to check earlier, but your are right. Mine is no longer made. Shurflo 5901-0211. It's worked like a charm for about 5 years. Have an unused spare too. My luck is never better than average.
To the OP's more recent inquiries, it is rated at 5gpm at pressure up to 60psi. I know I backed it down a little bit, because the factory max setting was kicking the hot water tank relief valve open.
Except on rare occasions, we never run the faucets at full pressure anyway, but it's nice to have if you need it. One occasion is that first shower, after a long passage, when back at a slip and water consumption is not an issue. Glorious.
I'm confused. Just about all the listings for pumps I look at have GPM and max psi listed. Since fresh water pumps are positive displacement, not centrifugal like many bilge pumps, the flow doesn't fall off much as the pressure increases. And in general, more amps means more flow.
I think Minne means variable speed, not variable pressure. Those pumps speed up or slow down to maintain the system pressure. Nice feature, though some have had reliability problems. Most pumps run only full blast and then turn on and off to maintain pressure. Cycling can be annoying at low flows without an accumulator.
SPXJohnson (Sweden) has recently introduced a 5 chamber wobble plate diaphragm pump for pressurized water service. Johnson marine pumps, to me, are the best value for long reliable service. Ive steadily replaced all my other onboard pumps to Johnson Pumps - RO feed, bilge, deck wash down, etc. .. all are wobble plate diaphragm pumps and all are noticeably quiet. More expensive than the available domestic pumps.
WM, Defender, and other typical recreational marine chandleries are starting to supply the Johnson potable water pump.
Such wobble plate diaphragm pumps are positive displacement pumps.
Ive steadily replaced all my other onboard pumps to Johnson Pumps - RO feed, all are wobble plate diaphragm pumps and all are noticeably quiet. More expensive than the available domestic pumps.
Rich, which pump are you using for your RO water feed?
We go through a water puppy about every 10 months and we cannot use a centrifugal one. I think the water puppy is about 3.5 gpm and I need at least that for sure.
Thanks.
Hmmm, the REMCO pump I linked to is also called "Aquajet" and has a 5-chamber wobble plate. It looks suspiciously like the Johnson pump of the same name except for color. Aquajet : Remco
The only difference is that it has been available to the RV and commercial markets for several years, while you say that Johnson's is a recent development.
Could it be that they are the same pump and Johnson is distributing it to the marine market? If so, one can save some money by going outside "marine".
I'd be careful about how much pressure you put into a small boat's fresh water system. I don't think most are designed for more than 60psi. I find about 45 works well on American PEX systems. Above 60 we start getting leaks in the PEX fittings. We tighten them but a few months down the road they begin leaking again. Not just this boat but quite a few others I've been on, too. Perhaps if one has a new boat, 60 would work for some years before the temperature and vibration begin to weaken them?
Right on target Capta. Its not only the hose but the less than adequate barbed fittings that leak and pop. For typical on-board use, above 30 psi seems more than necessary.
At the risk of derailing the conversation, what is the deal with PEX water piping?
I always used hoses made for potable water with hose clamps and fittings and that seems to last quite well and stand up to lots of pressure. Somewhere along the line people seem to have decided that PEX hose and fittings are the only way to go for potable water piping. I somewhat get it on homes, but I don't understand it on boats.
Can anyone fill me in on why PEX has become the 'go-to' potable water hoses?
At the risk of derailing the conversation, what is the deal with PEX water piping?
I always used hoses made for potable water with hose clamps and fittings and that seems to last quite well and stand up to lots of pressure. Somewhere along the line people seem to have decided that PEX hose and fittings are the only way to go for potable water piping. I somewhat get it on homes, but I don't understand it on boats.
Can anyone fill me in on why PEX has become the 'go-to' potable water hoses?
I had PEX fittings on my 1979 Pacemaker and have them on this 1981 ketch, so they are not new.
I like it because it has so many benefits over hose;
It is much smaller for the same ID, therefore much easier to run or replace
Being stiff, but bendable, it's easy to push through bulkheads or the like
It is tubing, not hose so it doesn't crimp or suck flat
It is food grade
It comes in different colors, so sea water can be green, fresh cold is blue and fresh hot is red, a nice feature
No hose clamps to rust or fail
no tool for installation or removal (on the new ones) of the tubing
No pipe fittings or thread tape required as there are a multitude of
coupling/connection options including valves
I believe it is much longer lasting than any hose and probably more chafe resistant
I think the newer fittings are much better than my 1981 ones and I intend to change over soon.
PEX isn't permeable to bio-organisms as is PVC, nylon, etc. One of the reasons that marine store water hose eventually turns black-ish is bio-organisms have penetrated into the surface of the polymer.
The Polyethylene used in PEX is of chemical low surface activity ... bio-organisms don't use it as a nutrient source; they metabolically 'eat' just about everything else.
Nylon hose-barb connectors used with common boat water hose starts to 'particulate' after about 6-12 months via the mechanism of hydrolysis - yum! Hose barb connectors are notorious 'dead legs' (high growth areas for bacteria, etc. in between the hose and the hose barbs) - prohibited in regulated food or bio-pharma NSF/FDA (and 'parve') water applications.
PEX is generally approved/cert'd. (by NSF) for potable water systems; most other polymer water hoses used in boats 'isn't'.
There's 'some' carcinogen concern with PVC and vinyl hose and tubing - the continual emission of PVC, vinyl, etc. free monomers.
Clorox, etc. added to potable water attacks PVC and vinyl, etc. - emission of unpolymerized monomers and particles.
PEX is considered an inert material for potable water and (most) water system sanitization chemicals.
Use a proper crimp-swaging tool with PEX, and one shouldn't have any leakage problems with the PEX connectors. The old hand-tightened. screw-on PEX connectors eventually 'creep' and release when in long term usage - obsolete, IMO.
'Shark-bite' connectors also work with PEX but not as well as swaged connectors; and can produce 'dead legs' - IMO.
PEX isn't permeable to bio-organisms as is PVC, nylon, etc. One of the reasons that marine store water hose eventually turns black-ish is bio-organisms have penetrated into the surface of the polymer.
The Polyethylene used in PEX is of chemical low surface activity ... bio-organisms don't use it as a nutrient source; they metabolically 'eat' just about everything else.
Nylon hose-barb connectors used with common boat water hose starts to 'particulate' after about 6-12 months via the mechanism of hydrolysis - yum! Hose barb connectors are notorious 'dead legs' (high growth areas for bacteria, etc. in between the hose and the hose barbs) - prohibited in regulated food or bio-pharma NSF/FDA (and 'parve') water applications.
PEX is generally approved/cert'd. (by NSF) for potable water systems; most other polymer water hoses used in boats 'isn't'.
There's 'some' carcinogen concern with PVC hose and tubing - the continual emission of PVC monomers.
Clorox, etc. added to potable water attacks PVC - emission of unpolymerized monomers and particles.
PEX is considered an inert material for potable water and (most) water system sanitization chemicals.
Use a proper crimp-swaging tool with PEX, and one shouldn't have any leakage problems with the PEX connectors. The old hand-tightened. screw-on PEX connectors eventually 'creep' and release when in long term usage - obsolete, IMO.
'Shark-bite' connectors also work with PEX but not as well as swaged connectors; and can produce 'dead legs' - IMO.
I've found the push in PEX fittings to be the most sensible for my use. Not only are all our fresh water system fittings PEX, but all the low pressure RO tubing as well. So simple, just install the receiving fitting and push in the tubing (about ½"). To remove the tubing, just push in and hold the flanges while pulling out the tuning. No tools or bother with fighting a hose off a barb.
Yup!
Ive used the 'speed-fits' in the past; didn't like them when they finally slipped off. Also didn't like the small ID of the connection.
They're apparently used a lot in the RV marketplace. The RV supply near where I live swears by them; but, I disagree.
There weren't any small SS unlocking tabs on the the ones I used..
Perhaps there is a newer version, as they do disconnect easily. I'll have to check
Hope you have fair winds and a good passage to St. L.
I hate hose clamps, which is a huge difference for me regarding pex vs. vinyl hose. Our boat's water piping system is extremely complex with probably 100 fittings or more. Simply installing or inspecting hose clamps throughout would be almost impossible. It would certainly be onerous. I never have to worry about sticking my hand up in some hidden plumbing area and pulling back a bloody sliced up piece of meat.
We have never had pex burst on us, but I have had countless reinforced vinyl hose balloon at fittings and burst.
Our pex system is 19yrs old now and there is zero growth inside it - and they have never been treated in any way. I could never keep growth out of the vinyl hoses on our previous boat without regularly flushing bleach through them. Even the outside of the pex where it runs through bilges and hidden places is clean. Our old vinyl hose turned black and sticky within a year or so.
Not to mention the price. Pex tubing is almost free and available at the hardware store, while even the best source for quality vinyl hose is much more expensive (beware cheap vinyl like found in hardware stores and west marine). Depending on which fittings you want to use, pex fittings can be cheaper than quality hose clamps alone. Our boat is plumbed with Qest fittings, and I get those for less than cheap hose clamps. If one is replumbing a boat, pex makes so much more sense on all levels.
If one is just replacing a relatively short length of existing vinyl hose, then maybe vinyl makes sense for ease.
Thank you all. I have had very little hands on experience with PEX and a lot with hose, but had noticed that PEX had seemingly become the industry standard. Hearing your comments is very helpful. I wish I had seen them before I replaced my water system two years ago.
Now back to the regularly scheduled program in progress.......
I have a Jabsco that is barely adequate. I want to replace it, but can't find a definitive source for rating freshwater pumps. I like FLOW and PSI. Not very concerned about amperage usage.
Anyone have experience with a particularly good pump or can otherwise point me towards a reference.
Since fresh water pumps are positive displacement, not centrifugal like many bilge pumps, the flow doesn't fall off much as the pressure increases. And in general, more amps means more flow.
My boat came with an approach I really like. The fresh water pump, the shower sump pump, and the stripping pump are all the same make and model pump. That means I can carry one spare and cover a lot of bases, and in extremis the shower sump pump is a hot spare behind that.
You really should have an accumulator in the system.
So many advantages for PEC already posted,, agree completely .IMO swage everything .when changing layout, just cut off the ends and crimp away. You can cut off the bands later for the parts bin. Clean cuts on the pipe end ensure good joints. Beware older sytems in grey PEC . pipe and fittings are not interchangable ,needs adaptors or replace all for new. The bands are different too. Why wouldn't you have an accumulator?
FWIW we replaced our functional--but very noisy--belt-driven Jabsco diaphragm pump with a Jabsco Sensor Max 17 Variable Speed Drive pump about 14 years ago. We kept the accumulator, which wasn't necessary, and it has all worked out well. We keep the old pump as a spare for the 27 old shower sump pump, which also acts as a backup manual bilge pump.
This thread, or me looking at it, must have jinxed my freshwater pump! For all I know it is original (1976!) and it was working perfectly until now (except for one little hickup 2 years ago, http://www.sailnet.com/forums/gear-...agnose-rebuild-par-jabsco-diaphragm-pump.html but I don't think this is related). It stopped working this week! Took out the pump and it turns out the pressure switch is kaput.
I actually found what I believe should be the replacement switch https://www.fisheriessupply.com/jabsco-36900-36800-36950-replacement-parts. So I could order it and hope that it really only involves screwing it in and connecting the cables. But it will cost me about $50.- (with s/h) and I will still have a 40 year old pump.
While i am in there, I might add an accumulator tank. Any reason this would not work? https://www.lowes.com/pd/Utilitech-2-Gallon-Expansion-Pressure-Tank/1038591 It has a definitely non-marine price and it is supposed to do exactly what I need it to do. Given that pretty much every house has one, I suppose they have the engineering on this thing worked out...
Not at all. The accumulator was fully functional when the VSD pump was installed. Since the pump is triggered by pressure, the only effect I can imagine is that the accumulator hold the pressure up longer as the water is pumped out, thereby reducing the cycling of the pump. I do notice that when multiple taps are open, as when I am trying to flush out the tanks after the winter, the pump runs noticeably faster, so I presume the accumulator is still functional.
Same accumulator I used. Keeps the pressure switch from stuttering. The Par rubber bits have a short life compared to the body.Pressure and bilge pumps have different size inlet/outlets,, not same pulley and belt and insert reed valves but kinda look alike. I found they last longer if you depressurize if leaving the boat for any length of time
Back when boating requirements were more modest, 20 psi was the norm. Somehow we managed. The lower pressure made the pump and it's internal bits more dependable, methinks. Higher pressure makes cleaning the toothbrush easier. It's a balance type decision.
Makes sense. I rather take a bit lower flow than having a hose burst. I was actually looking for a lower range but the lowest Square D pressure switch I could find is 30-50 PSI.
My Jabsco Par Max 17 VSD pump pressure sensor is set to 35 psi and it is adequate for multiple outlets. If you want to use if for a washdown, you might want a higher pressure, but 35 psi is more than adequate for showers, galley, head sink.
Wouldn't it to be possible to T two pressure switches in to the plumbing with different values. Wire an either or two way switch to .That way you can choose top shelf or prudent .Every thing would have to be capable of the higher setting .Incidentally I like the accumulator close to pump outlet to absorb shock wave from pump so switch doesn't.'t flutter
Yes, that's the plan at this time, have pump, switch and accumulator all pretty much next to each other. Will have to check (this weekend) whether I can fit the tank in there. There is space but access is not great, and I am not sure I can fit a tank through the access door.
I will start my own thread if need be. But with all this talk of an accumulator Tank maybe I need one. My pump cycles when not being used I haven't timed it so its not quick but annoying every once and a while. I even crimped the line at the pump and it stops short cycling and there are NO leaks and I've looked everything over pretty good. Not pex, regular clear braided hose if that matters. Sounds like a Tank would help.
It sounds to me as if there is something (as small as a hair) in one of the pump's diaphragms preventing it from sealing, if you are absolutely positive there are no leaks in the system, in or out. Sucking air in is as much a problem as water leaking out of a pressurized water system.
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