Shurflow pump problems

Discussion in 'Talkback' started by stewarl, Mar 4, 2002.

  1. stewarl

    stewarl New Member

    Got a perplexing problem with our TT water pump & don't know what's going wrong. I'll do my best to try to describe what's happening & hopefully, someone out there has an idea what we can do........

    We have a Shurflow water pump in our 2001 Aerolite TT that we've replaced 2x (luckily under warranty) due to the fact that it keeps back filling our fresh water tank when it's in use. My husband had put a check valve (?) on the line, but if the pump loses it's prime, the pump doesn't have enough "suck" to get the flowing the water again. He thinks it might be because the check valve isn't one made by Shurflow (it's just a generic one we got at an RV store) so it isn't compatable with the pump we have. The check valve stopped the backfilling, but it's no good to us since the pump then can't draw enough H2O to get itself going.

    What can we do about this situation? Camping season is nearly here in OH & I'd like to find some resolution to this before we start out again.

    Thanks, in advance, for the advice!
     
  2. C Nash

    C Nash Senior Member

    Shurflow pump problems

    Do you have normal pressure at the faucet when the pump is running? Does it build up pressure and cut off?

    Chelse L. Nash
    fulltimer03@yahoo.com

    Edited by - c nash on Mar 04 2002 10:43:04 PM
     
  3. stewarl

    stewarl New Member

    Shurflow pump problems

    Yes
    No
    After talking more with my husband, he came up with a better description of our problem..........
    Point of clarification on how our water system is arranged. A couple of reply messages mentioned a diverter valve or water intake valve. Neither (I believe) is installed on our system. The fresh water tank has a separate fill spout (direct to tank) towards the front of the trailer (on the input side of the water pump). The city water hookup located at the rear of the trailer is farther away (on the output side of the water pump). We do not use the water pump while connected to city water. When we do connect to city water (using a pressure reducer), there is a leakage back thorough the water pump and into the fresh water tank (takes overnight to fill the tank). The pump is supposed to have a built-in check valve, but it doesn't seem to stop the backflow. Has happened since we first bought the trailer and replaced the pump once after that. Hence the extra check valve. Can try different placements of the check valve (before pump, after pump, but definitely before city water) and see if that makes any difference.

    Does this help with diagnosing the problem?
    Thanks, Chelse.
    --

    Do you have normal pressure at the faucet when the pump is running? Does it build up pressure and cut off?

    Chelse L. Nash
    fulltimer03@yahoo.com

    Edited by - c nash on Mar 04 2002 10:43:04 PM
    [/quote]
     
  4. C Nash

    C Nash Senior Member

    Shurflow pump problems

    Still kind of confused about how this is happening. Is the water going through the pump and then returning to the fresh water tank via another hose? Sounds like there would have to be a check valve located in a by-pass somewhere and it is not working properly, maybe a o-ring that is out of place and leting water flow both ways. Did it work ok after installing the pump? What does the dealer say? If it has been a problem since new and they have records of such, it should still be under warrenty. Have you tried to get information from Sureflo? Could be that they have some defected pumps. Interesting problem, well not for you, so let us know how you correct.

    Chelse L. Nash
    fulltimer03@yahoo.com
     
  5. stewarl

    stewarl New Member

    Shurflow pump problems

    When hooked up to city water (shore connection), water is leaking back through the pump & getting into the fresh (I believe it's called potable) water tank. From what I can see, there's only one hose into & out of the pump. The city water connection ties into that hose "downstream" from the pump. We can't see where it ties in to look for a by-pass valve. The connection is in the wall behind the shower. I don't know how else to define this delema. From my end it seemed simple, but I've sure confused a lot of you out there with my descriptions. It worked (or didn't work, in this case) the same way even after replacing the pump. The dealer said the original pump had bad seals, so they replaced it. The backfilling into the fresh water tank (when hooked to city water) slowed, but didn't completely stop. Does sound like something wrong with the pump, now that you mention that. We'll check w/Shurflow & see what they say. Let ya all know what we find out.

    Thanks much for your help.
    --


    Still kind of confused about how this is happening. Is the water going through the pump and then returning to the fresh water tank via another hose? Sounds like there would have to be a check valve located in a by-pass somewhere and it is not working properly, maybe a o-ring that is out of place and leting water flow both ways. Did it work ok after installing the pump? What does the dealer say? If it has been a problem since new and they have records of such, it should still be under warrenty. Have you tried to get information from Sureflo? Could be that they have some defected pumps. Interesting problem, well not for you, so let us know how you correct.

    Chelse L. Nash
    fulltimer03@yahoo.com
    [/quote]
     
  6. C Nash

    C Nash Senior Member

    Shurflow pump problems

    You have described your problem very well. I have just never ran into this problem or heard of it. I think your problem will be in the check valve downstream from your pump where it ties into the city water connection. It is probably letting water by-pass and return to your fresh water tank. If this was happening your pump probably won't shut off. I really don't think it is flowing back through the pump if you have pressure at the faucetts with it running. Keep us posted

    Chelse L. Nash
    fulltimer03@yahoo.com
     
  7. rv wizard

    rv wizard New Member

    Shurflow pump problems

    I don't think you have a bad pump but a bad check valve as has been mentioned before. If the check valve located on the outlet side of pump back to city water connection is not stopping the city water (under pressure) from reaching the pump the pressure could seap through the pump and flow back into the fresh water tank. I bet if you replace the check valve all will be ok.

    Mike, Amy, Ashley, Candi
    2000 Gulf Stream Scenic Crusier on Spartan M.M. 330 hp. 6 spd. Allison
    #3 & #8 NASCAR
     
  8. middle.american

    middle.american New Member

    Shurflow pump problems

    I'm replying for the sake of future RVers researching the problem of backflow and or failed seals or pump check valve. My pump just gave way to city water back pressure today. I don't have a cutoff to keep pressure off the pump.

    Check Valve (as suggested by others) Though check valves can be a good add-on they, by themselves, cannot replace the benefits of an accessible plumbed in cutoff valve after the pump.

    The best solution is to have a cutoff and a check valve on both sides of the pump. Everytime you're on city water simply cutoff the pump outlet. If you happen to forget the cutoff then the check valve will stop the backflow pressure from reaching the pump thus putting pressure on the seals.

    It seems most effective to have a check valve placed on the line nearest the fresh water tank. That way there will always be water in the line leading to the pump helping it to maintain prime.

    If you're loosing prime there must be a slow leak in a pipe fitting allowing air to seep into the line. Or worse, there is a leak in the pump seal allowing air into the pump allowing the water to drain back through an also faulty check valve.

    I hope this helped someone. Perhaps not stewarl from the original 2002 post but hopefully someone in the future. I'll be adding cutoffs and check valves tomorrow after I rebuild the seals that failed on my one year old Shurflo 5.7 gpm.

    Please feel free to help me better this check/cutoff idea and/or correct me.
     
  9. USMC

    USMC Member

    Shurflow pump problems

    I may be missing the point of the problem you discribed, but I thought I would throw in my 2 cents.

    on my system I have a cut off valve between the hot water heater and the fresh water holding tank, If I were to open that valve I would have the same problem as you are having with the feed back, I keep that valve closed many people over look that. just a thought. later Jim
     
  10. Grandview Trailer Sa

    Grandview Trailer Sa Senior Member

    Shurflow pump problems

    This may sound like a silly question, but is the pump installed correctly? You say water goes through the pump, into the tank. And you also say you don't have enough pump pressure to prime itself. Sounds like it is installed backwards.

    There is a built in, one way check valve, in each and every pump. It prevents water from the city water side going THROUGH the pump and filling the storage tank, but allows the pump to work and empty the tank. It does not matter where the city water comes into the trailer. I have had to replace 3 pumps over the last 10 years because of a leaky valve. It seems hard to believe, but I think you have found 2 bad pumps, if they are installed corectly. You can save some money by buying just the pump head, if your motor is OK.

    This check valve is overlooked when people winterize if they blow out the water with air. The check valve also prevents the air from emptying the pump and they freeze ruining the pump.
     
  11. TexasClodhopper

    TexasClodhopper Senior Member

    Shurflow pump problems

    This has to be a record! Revitalizing a thread after 4 years! Yea! ;)

    My pump also has its own check valve built in.

    How could the pump pump water if it was backwards?
     
  12. Grandview Trailer Sa

    Grandview Trailer Sa Senior Member

    Shurflow pump problems

    Wow, did not look at the orginial dates...........
     
  13. middle.american

    middle.american New Member

    Shurflow pump problems

    I revived the old post because there is no other post on earth addressing this problem (Shurflo centric). Thus my intro/disclaimer "I'm replying for the sake of future RVers researching the problem of backflow and/or failed seals and/or pump check valve....."

    My pumps seals gave way to city water pressure. I thought replying and suggesting a cutoff after the pump and a backup check valve could help someone in the future to save their pump. I suppose it wouldn't hurt to start a new post as some kind of advice columnist, but, I knew that those who subscribed to the original post would be sent an email and might able to help me flesh out the best possible plumbing design as well.
     
  14. middle.american

    middle.american New Member

    Shurflow pump problems

    Grandview Trailer Sales, when you say "when people winterize if they blow out the water with air" do you mean forcing air (CO2 or something) 1. backwards towards the pump 2. from the tank fill or other fitting through the pump out the faucets, or 3. just running the tank dry by dry running the pump.

    I would assume that just running the tank and pump dry would allow enough water to be removed from the pipes to avoid ice expansion even with a check valve.

    What do you think? It seems a good idea to have a secondary/backup check valve and cutoff after the pump. Obviously, pump check valves are poorly designed and fail often.

    Thanks
     
  15. Grandview Trailer Sa

    Grandview Trailer Sa Senior Member

    Shurflow pump problems

    There is a blow out plug you can screw into the city water inlet then hook up air pressure from an air source. You apply pressure while having your faucets open and you will remove the water from the lines. Your pump running dry will not do it. Once the pump looses its prime, it won't move any more water.

    I don't like that way of winterizing. With the check valve between the pump and city water source, water can be left in the pump, which will freeze and ruin the pump. I like to pump RV anti freeze through the system. That way I know I have not left water anywhere and I will be ready to go in the Spring.
     
  16. middle.american

    middle.american New Member

    Shurflow pump problems

    Yes, this should be a new post, but for the sake of continuity...

    THE BEST OVERALL SOLUTION FOR PUMP PROTECTION
    How about replacing the standard T fitting with a 3-way valve like one of these to divert water from EITHER the pump OR from city water. Currently, I either have to cap the hose inlet when the pump is on or I must rely on the pumps built in check valve to hold when using city water.

    As we have previously discussed, if the pump's check valve fails water can flow backwards through it over filling the tank. If not that failure, then high pressure can blow out the pump seals. (Mine did! $80 replacement) A 3-way toggle valve seems like the perfect solution. It can be toggled for whatever water source your using keeping water pressure from reaching the other source's line.

    Mounting and extending the handle outside of the heated compartment is the only trick. In my rig I can easily mount these through the 1/4'" thick basement wall from the heated compartment into the area where the other valves are accessible.

    If there is a way to extend the handle a few inches you could even have it outside of the RV near the fill ports in a recessed enclosure. Now that would be a classy install. This type of toggle valve should become standard equipment on every RV.

    3 Way Valve and [​IMG]

    3 Way Valve2 and [​IMG]
     

Share This Page