Water pump cycling - new pump

[ualdriver]

Hello-

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

I recently installed the pump above to replace my malfunctioning water pump. When the pump is providing pressure for the MH, for example when someone is taking a shower where a steady flow of pressurized water is needed, should the water pump cycle on and off in short, say one-second intervals to maintain water pressure, or should it be running continuously?

I thought my old water pump, which was the identical model, ran continuously, but my memory could be incorrect. It would seem to me that having a pump like this constantly cycle on/off in short intervals would shorten the life of the pump, but perhaps that is the way they are designed.

Thanks.

[Bangorbob]

Interesting. I just changed my 12 yr old pump to the same pump. Honestly, I can remember if my old pump ran constantly when taking a shower or anything. I do know my pump leaked and my outside shower (that I have never used on any rv). Old one did take some time to charge because of leaks. New one fires right up and seems to have more pressure.
I'll be watching this also. Thanks.

[cavie]

Originally Posted by ualdriver

Hello-

https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

I recently installed the pump above to replace my malfunctioning water pump. When the pump is providing pressure for the MH, for example when someone is taking a shower where a steady flow of pressurized water is needed, should the water pump cycle on and off in short, say one-second intervals to maintain water pressure, or should it be running continuously?

I thought my old water pump, which was the identical model, ran continuously, but my memory could be incorrect. It would seem to me that having a pump like this constantly cycle on/off in short intervals would shorten the life of the pump, but perhaps that is the way they are designed.

Thanks.

The pump runs when water is on. Shuts off when you turn off the water as I remember. I'm on a seasonal site. The only time I run the pump is to winterize. That how mine works.

[Civdiv99]

The “one second intervals” is what’s throwing me for a loop. My pump cycles because it builds to pressure faster than it’s relieved. Little stuff like brushing teeth the pump comes on when pressure drops, but builds right up and cycles off. But it’s off and on times are like 10 seconds at a stretch. I’ve pondered a pressure tank to smooth it all out, but it’s not like it’s a “problem,” so meh.

Shower I dunno it may have to stay on but if it cycles I haven’t noticed.

I’d say your rapid cycling is unusual but try turning on shower, open some faucets, flush the can, etc. with all that going it it shouldn’t cycle. It should just run. Turn some items off one by one and you’ll get to a point it cycles, but not one second at a time. Keep turning off faucets and the cycling times should shorten. If so, I wouldn’t worry about it too much, but it’s also possible you have a flakey pressure switch on the pump perhaps?

[ualdriver]

Originally Posted by Civdiv99

The “one second intervals” is what’s throwing me for a loop. My pump cycles because it builds to pressure faster than it’s relieved. Little stuff like brushing teeth the pump comes on when pressure drops, but builds right up and cycles off. But it’s off and on times are like 10 seconds at a stretch. I’ve pondered a pressure tank to smooth it all out, but it’s not like it’s a “problem,” so meh.

Shower I dunno it may have to stay on but if it cycles I haven’t noticed.

I’d say your rapid cycling is unusual but try turning on shower, open some faucets, flush the can, etc. with all that going it it shouldn’t cycle. It should just run. Turn some items off one by one and you’ll get to a point it cycles, but not one second at a time. Keep turning off faucets and the cycling times should shorten. If so, I wouldn’t worry about it too much, but it’s also possible you have a flakey pressure switch on the pump perhaps?

Yeah, I should turn a bunch of stuff on and see if it runs continuously.

I was wondering if there is some sort of adjustment setting on the pump to perhaps adjust the sensitivity of the pressure switch on the pump.

I really don't care if it cycles on/off as we can barely hear it and the water streams continuously (i.e. it doesn't "pulse" in rhythm with the pump). I'm more concerned about pump longevity.

[CJ7365]

You can adjust the sensitivity of the pump.


How To Adjust The Pressure Switch On A SHURflo Water Pump

http://lazydazearticles.blogspot.com...008-water.html

[ualdriver]

Originally Posted by CJ7365

You can adjust the sensitivity of the pump.


How To Adjust The Pressure Switch On A SHURflo Water Pump

The Lazy Daze Companion: Adjusting The Shurflo Revolution 4008 Water Pump

Excellent video!!!

Thanks! I'm going to play with that tomorrow.

[Bob Hyatt]

You CAN adjust the pressure sensitivity. You CAN put your foot under a running lawnmower too. Question is, SHOULD you adjust it? Most likely not. Otherwise you will get complaints from wife about the water is surging as it comes out of the faucet, because the pressure drops too low to produce reasonable flow, then pump kicks on and pressure jumps, Then it cuts off and there you go. Pump doesn't mind turning on and off. The more quickly it cycles, the more even your water pressure will be. The more slowly it cycles, the bigger the pressure swings will be...

Only time you should be concerned is when you hear it cycling with any frequency and NO water is being used. Bad check valve or leak somewhere most likely, neither of which you want to ignore.

[Old-Biscuit]

The Link to the lazy daze adjustments for bypass and pressure switch is good way for that pump


First you should check couple of things:
Showers typically have flow restrictors either in hose connections or handle.
They WILL cause high pressure/flow pump to cycle


Remove shower handle...turn water on.
Does pump still cycle?
Remove shower hose from faucet.....turn water on
Does pump still cycle?

[ualdriver]

Originally Posted by Old-Biscuit

The Link to the lazy daze adjustments for bypass and pressure switch is good way for that pump


First you should check couple of things:
Showers typically have flow restrictors either in hose connections or handle.
They WILL cause high pressure/flow pump to cycle


Remove shower handle...turn water on.
Does pump still cycle?
Remove shower hose from faucet.....turn water on
Does pump still cycle?

Through Old Biscuit........thanks.

Old Biscuit.......will follow your steps tomorrow hopefully when back at RV and report back if still having issue......if this even is an issue.

[Rossi6998]

[ualdriver]

Originally Posted by Old-Biscuit

The Link to the lazy daze adjustments for bypass and pressure switch is good way for that pump


First you should check couple of things:
Showers typically have flow restrictors either in hose connections or handle.
They WILL cause high pressure/flow pump to cycle


Remove shower handle...turn water on.
Does pump still cycle?
Remove shower hose from faucet.....turn water on
Does pump still cycle?

Old Biscuit-

Thanks for your time.

When I removed the shower handle (which I know is a "water saver" handle and most likely has a restriction), the pump pulsed.

When I removed the shower hose from the faucet, I could physically see a disc with a small hole in it, which restricts the flow of water. The pump pulsed when I turned the water on.

So I left the shower faucet on, then went and turned the sinks on. With the increased demand, the pump ran continuously without pulsing.

I assume, then, that the pump cycling is normal when running water restricting devices? And if it is normal, I guess pumps like these cycle all the time in the 1000s of RVs out there, and it doesn't have a detrimental effect on the pump?

Thanks.

[Podivin]

Originally Posted by ualdriver

I assume, then, that the pump cycling is normal when running water restricting devices? And if it is normal, I guess pumps like these cycle all the time in the 1000s of RVs out there, and it doesn't have a detrimental effect on the pump?

Thanks.

Correct, this is normal pump operation - it's working as designed.

[ualdriver]

Originally Posted by Podivin

Correct, this is normal pump operation - it's working as designed.

Thanks!