The pump is the small 2.5 gpm Shurflo base model as I recall without digging it out to read the label.
Symptoms: A couple days ago the pump began occaisional split second hickups as if there were a slow dripping faucet, but there wasn't. The frequency has increased to the point now it does it every 30-45 seconds. (except I turn it off now when not in use). After a while of being off, when I turn it back on it has to repressurize the line and there is a very small amount of air at the faucet.
Troubleshooting: I thought it must be a leak, but have checked and double checked. No leaks. I then thought maybe the toilet was passing some to the tank so I turned off the supply to the toilet. No change. I turned off the supply to the hot water side. No change. So I closed the shut off valve I have on the output side of the pump. No change. So it is definitely the pump.
Does it make sense that a check vavle or other structure inside the pump is allowing pressure to bleed back to the tank side? If so, is it reparable and practical to do so or is it just time for a new pump?
It's the check valve, upgrade don't fix, and if you want to do yourself a favor you'll get one of the rotary vane pumps that don't hammer the lines and make all the noise... :)
Mike they have a kit for those doesn't cost much if it works for you rebuild it but most of the time that problem is caused by air in the system also check your hot water heater safety valve outside they are prone to leak a little
.
good luck
I replaced one 5 years ago that started leaking. The "new" one started leaking on our trip south last week so i pulled it out after we got here and took it apart. Cleaned it up, put it back in and it still leaked. Went and got a new one. :) They were all the 2.8 gal pumps and have a 2 year warranty. We fulltime and use ours all of the time so it gets a lot of use.
I went through this a couple of times. Just gut the check valve and add a new decent quality external valve.
Len
On the subject of water heaters, make sure there is some air in the top of the heater tank when refilling after draining.
If the tank is full of water it will seep from the pop-off valve.
Back to the original post, what's happening is that some "stuff" has gotten lodged inbetween the internal valves and their seats (there's three) inside the pump, causing the outlet pressure to slowly leak down. Then when it gets to a certain level the switch turns the pump on and pumps the pressure up, and this repeats. AS the "stuff" accumulates, the problem happens more frequently.
In my pump, this happened because little shreds of tank plastic from the manufacturing process got into the valve. I took the pump apart and found the culprits, removed them and it fixed it... for about a week, then it happened again. Same stuff. The fix was getting the little add-on strainer that they sell and installing it on the pump's inlet. No more problem but the strainer has continued to catch the plastic stuff.
There you are... simple fix....
Mike,
What the Boogieman said.
Mine had hard water deposits that did the same thing.
What is the source for that screen?
The part of the story that confuses me is your report that the faucet has air in the line when you restart the pump after it sits. Is your pump located higher than your tank? If you have a water pressure gauge on your system to be able to anticipate pump failure....and....you have a valve in the line right after the pump....you can pressurize your line and then turn of the valve and watch that the pressure holds. If the pump continues to cycle you know where the problem is.
HTH
John
The screen is a standard little part that surflo makes... "strainer" ...plugs right into the pump, or screws on depending on the model.
(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fwww.heartmagic.com%2Fsurflo.jpg&hash=df37d035a14c95592c8952a473a0f03a273eb64a)
About the air it could be dissolved air or bubbles that got big when depressurized. Water contains a LOT of dissolved air and it comes out quickly when depressurized...
Thanks for all the informaiton and tips. I will probably get it out and open it up to try to fix it then. That solution fits my budget best. Someday when my budget permits I will probably upgrade to a dual pump system so I have redundancy. I can't complain about this little pump though, it has held up dependably for about a year under full-timer use, so it has done some work.
Regarding the air at the tap. The pump is pretty much the lowest point in the system. So if the check valve is allowing it to depresurize and I have the pumped turned off to avoid this problem, after just a little aiir was released from the water it would go to the highest point. That would be the kitchen tap. Then gravity would pull down on the water, creating a vacuum at the air pocket at the top. The vacuum could further encourage the release of air from the water. When the pump is turned back on, then the air pocket is pressurized.
The kitchen tap also does occaisionally drip. In reverse, as a small air pocket formed gravity caused it to form a vacuum, it could pull minute amounts of air back through the tap.
In any case after a few hours, it is only a very small pocket of air. Just enough to make the faucet give the initial "pfftt!" when turned on after the pump is switched back on.
Again, thanks for the information and tips.
Mike,
My pump is also at the lowest point....right next to the tank outlet port. I see most of them put in that way. I wonder about that as I think they will draw water 6 feet to prime...it is quite a bit. Mounting it higher would allow the pump to be removed for service and not have all the water be lost. 20/20 hind sight on my part.
Glad it is working out.
Thanks Boogie,
John
Meow....
Quote from: JohnEd on November 06, 2009, 07:55:17 PM
My pump is also at the lowest point....right next to the tank outlet port. I see most of them put in that way. I wonder about that as I think they will draw water 6 feet to prime...it is quite a bit. Mounting it higher would allow the pump to be removed for service and not have all the water be lost. 20/20 hind sight on my part.
Should not a good busnut have a shutoff valve on the outlet from the tank before the pump?
I'll admit I don't have a valve and you got me to thinking. I carry a spare pump, but if I ever had to replace it I would lose a lot of my fresh water. I don't know if I could put my pump above my tank without putting it inside the bus.
Brian,
I think just placing it near the top of the tank would solve the problem. And, who among us has a tank taller than 6 feet.
2 cents
John
I could be wrong, but it seems to me like unless a person used a floating pickup tube, it would still pick up sediment and plastic debris from the tank.
My pump is on the opposite side of the bus from the tank but at the same level as the bottom of the tank with a valve each side of the pump to allow me to R/R the pump without loss of water. When I do this work on it, I plan to install a filter to protect the pump.
I have a drain valve on the bottom of the tank so i just filled a few 5 gallon jugs and used it to water the plants in the yard. At the most i would have 100 gallons of water to drain. :) Don't think i have enough room to install a shutoff valve by the pump, will have to take a closer look tomorrow.