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NXR 11-19-2019 06:13 PM

What is your experience for water pump cycling intervals?
 
We have a Shurflo 8008 pump that's supposed to shut off at 55 lbs psi and turn on at 40 lbs psi. I sanitized the system yesterday and had all faucets open while draining the tank. Everything was refilled last night and I ran the faucets to purge air out.

But this morning the pump ran when I turned the switch on and it ran for several seconds. Pre-sanitization this did not happen but we do not use the pump that much. I did not try turning a faucet on before switching the pump on to see if all of the pressure was gone.

I'm thinking (hoping) there might still be some air in the system and that caused the pressure loss. I checked all of the piping I can see and there are no leaks. I did have the water filter out for the sanitization so I put a paper towel under the filter overnight and it was dry this morning.

I opened all of the faucets for thirty seconds again and there may have been some air in one because it kind of thumped the first time when hot and cold were turned on but not again. Definitely no sputtering, though.

I turned the pump on 2.5 hours later and the pump did not run.

So I was wondering what your experiences are for pump cycling. I know frequent cycling can indicate a leak but what is "frequent"?

The concern, obviously, is that when we're on city water there will be no audible indication of a leak unless it's really large. And then it will be me screaming. :)

Thanks,

Ray

Jim_HiTek 11-19-2019 07:10 PM

That pump is a handy 'telltale' so I'd keep using it until you're convinced it's not leaking. Just turn off the pump before bed and open a faucet for a couple seconds and any leak will be minor.

I don't think you have anything to worry about but it's best to keep an eye on it. I think there were probably little pockets of air all over your plumbing system and that air is migrating out as it feels like it.

What I've found is that the pump running a couple times during atmospheric pressure changes isn't unusual so if the weather is changing, I don't worry about a couple runs of a second or two. Typically, 2 runs of the pump per day is typical. More than that, I start looking at the faucets and showers. (When I'm asleep, I wouldn't know, but if it runs while I'm in bed before going to sleep, I shut it off).

The other thing that can cause this is air in the shower hoses. I mention that for any lurkers that might have happened onto this thread. So make sure you run the showers for a second or two.

NXR 11-19-2019 09:13 PM

Thanks, Jim.

If it had just run for a second or two I'd just write it off but it had to be a full five seconds or more. I just turned the pump on, 5:45 after I ran the faucets, and the pump did not run. I did run water through both hot and cold in the shower earlier but I'm not sure if I ran the wet bay shower yesterday after refilling. I definitely did not open the wet bay shower today. Thanks for the reminder. I also did not run the washer/dryer.

Tomorrow morning will tell. If it's another five or more seconds I'll start digging further.

Ray

NXR 11-20-2019 09:37 AM

1 Attachment(s)
And the result this morning was (drum roll):

The good news: After about seventeen hours, turning the water pump on did not cause the pump to run!

The not-so-good news: I had previously found a small amount of water on the floor of the compartment where the water pump is located, a few square inches on a paper towel. Using the paper towel method it appeared it was coming from the Shurflo pump inlet screen assembly. It went two days with no dampness and then I found some last night.

A friend suggested placing a bowl under the assembly to see if it collected any water. I was able to fit a very small Tupperware lid underneath it and this morning it did have some water in the lid. The picture shows about 18 hours of water.

The dealer had this assembly off a few weeks ago to clean some debris out that they thought was causing pump surging so I notified them this morning. The water pump compartment is an outside compartment and is lined with foil insulation as part of the arctic kit. Since this assembly is on the inlet (low pressure or suction side of the pump) it could not be the source of the aforementioned problem but needs corrected nonetheless.

I checked it over with an inspection mirror and found no evidence of where the leak is, unfortunately.

Thanks again,

Ray

Jim_HiTek 11-20-2019 09:47 AM

With my old pump, I did use a pair of channel locks to cinch the inlet and outlet pipes tighter to the pump threads.

For the bowl, I slathered the threaded part of the clear bowl with Vaseline after cleaning, before reinstalling. Wasn't going to interrupt my trip just to stop at a dealer about that tiny leak. That stopped mine from leaking and it never leaked again over the 6 odd years of ownership. Mine was a bit different from yours though, but perhaps that method would work on yours too?

But like that label says, hand tighten, so you could do that too.

Jim_HiTek 11-21-2019 10:12 AM

I should mention that 5 secs isn't all that unusual for the pump to run when a shower hose is filled with air. The outside shower is famous for causing that. The pump has to compress that air before it gets up to pressure and shuts off.

NXR 11-21-2019 05:03 PM

Last night the pump went "blurt" for a fraction of a second. 24 hours later I turned the pump on and it did not run at all. So I'm either good to go or the pump went bad. :)

Ray

Jim_HiTek 11-21-2019 09:06 PM

Quote:

Originally Posted by NXR (Post 5047321)
Last night the pump went "blurt" for a fraction of a second. 24 hours later I turned the pump on and it did not run at all. So I'm either good to go or the pump went bad. :)

Ray

HAH! You are a jokester, Ray. Left us hanging too. Bad pump or good to go??

NXR 11-22-2019 10:21 AM

Darn good question because I never actually tried it. So I just did. The pump did not run until I opened a faucet. So it probably was just air causing the pump cycling.

I tried to loosen the "hand tighten only" part of the inlet screen assembly and could not. But this morning I felt some water where that assembly connects to the water pump. There's no actual fitting so I just tried to rotate the whole inlet filter screen assembly. It tightened to the pump maybe 1/4" of rotation so hopefully that's all it was.

Ray

NXR 11-24-2019 11:09 PM

What is your experience for water pump cycling intervals?
 
And for two days there has been no water seepage from the pump inlet screen filter area. Amazing what happens when you tighten loose stuff. From my poor vantage point it looked like that thing was part of the pump but it actually just threaded directly on to the pump inlet fitting.

Ray

Soppy 11-25-2019 07:32 AM

You could have a slightly leaking check valve in the pump. This would prevent the pump from holding pressure and allowing the water to return to the tank.

richard5933 11-25-2019 07:46 AM

After introducing air into our pressure tank, it can take a few days until the pressure will hold overnight. Until then, the pump will cycle for a few seconds when turned on in the morning. Never been able to find a leak, and after a few days it stops.

My guess is that there are some small air pockets that just take a bit to work out.

NXR 11-25-2019 02:30 PM

Quote:

Originally Posted by richard5933 (Post 5051541)
After introducing air into our pressure tank, it can take a few days until the pressure will hold overnight. Until then, the pump will cycle for a few seconds when turned on in the morning. Never been able to find a leak, and after a few days it stops.

My guess is that there are some small air pockets that just take a bit to work out.

Yup, that is exactly how this worked. It's only the second time I've sanitized the tank and I probably just didn't know to watch the pump cycling before.

Ray


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