Still Water Pump issues

[RonS]

I posted this under plumbing above but will also try to get answers here. I have the on demand type pump 5900 by Surflow and it no longer pumps up to full speed/pressure. Surges and goes down to nothing for a few seconds, other times will not even kick in when water is being used. This has been ongoing issue, and pump has been replaced twice, and then only worked properly for a short time. Something is not right. I have replaced all the filters, checked all the water lines as far as I can reach. I'm thinking maybe something in the fresh water tank or water line plugging it up and not allowing pump to operate?? Maybe when the holes for the various hoses/connectors etc that the plug or drill fillings fell into the tank? Any ideas of what to try to make pump operate, hard to take a shower using the pump, so always try to be on city water.

[Caseyj]

Ron -

This is basic stuff that I am sure you have already tried but check out the hot water tank to make sure it's not full of air. Turn on the pump and leave the hot water faucet open until it stops sputtering this will indicate that your pump is not fighting air pressure.

Next, check to make sure all of your inlet valves are open with the exception of your winterizing hose. All valves knobs should be parrallel to the hoses. The winterizing hose should be cross wise to the hose to indicate shut off.

Your pump should run continueously with a faucet open unless you have an accumulator installed. This unit will allow your water to be shut off and on with out the pump continuously running until it reaches a bottom pressure of about twenty #'s.

If the above doesn' work, I would also suspect some debris either in the tank or in the inlet hose dis-allowing adequate water to the pump. If you want to test this therory, close all your valves and take a jug of water, open your winterizing valve, open one faucet. place the hose in the jug and see if you get full pressure at that faucet until the jug empties. This will ensure that your pump is ok and the suspect would be in the suction hose to the fresh water tank or debris in the tank itself. Good luck!

[Caseyj]

Ron -

While reading my response above, I left out that you will have to leave one of your lines open if you decide to do the test on your pump. Also, make sure you close your winterizing line when you put things back in order.

[RonS]

Caseyj - I did not think to test the pump that way. I will give it a shot.
THANKS!!

[Thom]

Ron, we went thru 4 of the 5900's ans simply deciided to forget them and had a dirt garden variety 2.8 installed. Not as much water pressure but it works dependably. We checked everything possible without ripping out the underbelly and chasing the lines..

\Thom

[RGordon]

Sounds to me like you have a air leak in the suction of the pump, either the valve for the external line for antifreeze insertion or the clear strainer bulb on the suction side of the pump. My strainer bulb cracked this winter with antifreeze in it (another lesson learned for me to drain after winterizing system). I would find the filler line for antifreeze and align valve to line instead of tank and like someone else mentioned, place a jug of water and insert hose into it and see if this makes a difference. I would bet you have an air leak in the suction strainer area causing pump to cavitate and fluctuating water pressure.

[morscuba]

Had the same problem. I found the inlet (from the tank) hose connection into the pump was not tight at the connection. Had to remove the type clamp that DT used and put a worm clamp on. have not had a problem since. GOOD LUCK