Shurflo Onboard Water Pump

[SirRogerFFS]

Hi To all you Techies out there . Sir Roger is still trouble with this pump. Earlier on the year my Flo Jet pump died .I went to our dealership who could only supply me with a Shurflo . Now this pump has been a complete nightmare .After fitting it we primed as per Swifts handbook and at closing the taps the we get a horrendous knocking that goes all through the van . We put up with it for our first tbreak this year then back to storage and prime it again where we didnt have one splutter from the taps just this knocking when the taps turned off . I thought I will accept that but when went away a week ago the knocking from the pump appeared to be when you open the as well as closing it . It was suggested I fit a none return valve to the pump which did help on the cold side ,little or no difference on the hot so I have now put anther non return to the other side of the pump which has stopped the banging when you open the tap but still there on closing the taps . I niw have another problem that I cant Identify within the van and that is an anti surge valve in the rear of the van . What does it do ?I am ready with the matches and lighter fuel ready to set fire to it . Oh also went to dealers today and passed this problem to one of there bods who suggested it maybe something on the water heater that has a cleanable, replaceable valve I cannot locate this without undoing things Im not sure of. All this just by changing a pump so please I hope somebody has the answer.
Sir Roger

 

[ProfJohnL]

Hello Your Lordship.

The Shurflo pump will already have non return valves built into it, so it shouldn't require extra NRV in teh adjacent pipework, but having fitted them it should not radically affect this type of pump. They also have a pressure switch built into them which is usually factory preset.

I wonder if the pressure switch threshold is set too high, which will make teh pump more noisy as it turns off after the taps have been closed. It would be worth checking the pumps installation instructions for any advice about setting the pressure switch. If there is no recomendations, then if it is adjustable then reducing the" switch off" pressure may help.

 

[pitpony]

Sir Rog,
I had a similar problem with my flojet on board pump which was mounted directly on to a piece of 10 mil ply at the front end of the caravan under the seating and when we opened the taps the noise from the pump just went through the front end of the caravan not helped by the direct mounting on to the ply, I then put four rubber mountings between the pump and the ply which reduced the noise to an acceptable level,

 

[SirRogerFFS]

Hi Prof thank you for you input but this pump has no adjustment to it at all .I could have added more to this thread but I didnt want forumites falling asleep. Everytime we have tried to prime the system we have drained the water heater and every time its full of air trying to find where the air is getting in is nightmare hence the NRV each side of the pump. I have now got the knocking on the cold side to a quite good level and only knocks when I close the tap but did know and bang when we opened a tap (some Improvement ) The hot is the same but at close of tap runs on longer and bags around after the pump has repressured .I have had the pump out rempounted it on rubber legs and a 10 mm piece of rubber . I am now out of ideas Pitpony this is a Shurflo pump not a flojet the shurflo is replacing a dead flojet
Sir Completely fed up Roger

 

[chrisn7]

. Everytime we have tried to prime the system we have drained the water heater and every time its full of air trying to find where the air is getting in is nightmare hence the NRV each side of the pump.

I don't understand this sentence. Are you saying you have drained the system, then primed it, but somehow it still has air in it?

 

[SirRogerFFS]

Hi Chrisn7 Sorry if I didnt make that clear.. Shurflo is supposed to be self priming but that didnt work so what we did was prime the system to the book. ie fill aqua roll turn on pump Open hot tap til just water flowing then turn to cold position and then carry on to the other taps this then carries on and fills the on board water tank and yes we still manage to get air I have reduced it on the cold side but on the hot side it over runs and and knocks but Im told this could be what shurflo pumps do. Thanks for your reply .
Sir Roger

 

[ProfJohnL]

Hello Roger

The fixes you have tried and the symptoms you describe don't seem to have got to the bottom of it , I,m concerned that the bits your adding are not going to fix it, but it will complicate the picture further.
Its always a lot of guesswork trying to resolve problems of this nature through a forum, I'm pretty certain that if I was actually attending your caravan, you could have shown me what happening , and the noises your trying to describe, and I'd have identified the cause within a few minutes.

We could spend a longtime trying to get to grips with the different ways different may describe a noise, which could change the perception of what going on quite dramatically.

As the simple things haven't worked so far clearly there is more going on than is easily understood, and I suggest you would be best to get a mobile caravan service guy to check it out for you.

 

[SirRogerFFS]

Prof. If you want to pop round to my van please do .. Shall I put the kettle on ?

 

[Raywood]

Our Avondale had the Sureflo pump and put simply nit was noisy. We did speak to a caravan engineer about this and he confirmed that it was a problem with them and his customers had tried various things like putting carpet under it but nothing worked. Even we replaced ours after frost damage the new one was just the same and we just lived with it on the basis that the tap is normally only on for very short bursts so it was not a problem to us.
The big advantage of the on board pump is no one can steal it as that has happened with a drop in one.

 

[chrisn7]

So, you you are filling boiler, pipework, then the onboard tank. This will require at least one Aquaroll - at the risk of asking the obvious, have you re-filled it?

 

[SirRogerFFS]

Hi Chrisn7 Yes The first aquaroll fills the water heater and then it goes on to fill the onboard tank at least 3 barrels of water for complete system. 1 Fill aquaroll turn pump open hot side til water flows freely the turn to cold side and carry on to doing the same to the other taps of course this will now fill onboard tank. Thanks for your response
Sir Roger

 

[Mike_374351805]

Hi Sir Roger. This may be a little late. Which model Flojet are you looking for? I have a R3426-500 that I bought as a spare for my Swift which I no longer own.
Regards, Mike

 

[SirRogerFFS]

Hello Mike. Thanks for looking in. I wasnt really looking for a flojet pump as had to replace my flojet with shurflo that is actually giving grief.Your flojet is exactly the same as the one I removed I am pig sick now cos I couldnt get a flojet replacement. I am at the moment struggling with a £ 90s worth of pump. Just out of curiosity what would you be asking for your pump.
Sir Roger

 

[Mike_374351805]

Hi again. I was thinking £30 plus postage. Mike

 

[SirRogerFFS]

Hi Again . Mike I would love to say yes but I feel I should really be sorting this one out although so far I hate to think how long I have worked on it. It works but its noisy when you close the taps and when it repressurises you would think the pipes were falling off.Thanks for letting me know Mike
Regards Sir Roger

 

[pitpony]

Sir Rog,
When I was having my knocking problems which I described earlier, I also found that I was having a lot of vibration noise from the pipe work when the pump was running, when I applied pressure to the pipe work the noise reduced I then placed pipe insulation to the pipes and that reduced the knocking noise level in the caravan,

 

[Mike_374351805]

You're welcome. Mike

 

[SirRogerFFS]

Pitpony I appreciate your thoughts. Some posters have missed the point that Im convinced the knocking I am getting is air..Now to prime the system from the beginning with the on board tank the system must be empty every time I try a new approach to stop the knocking I drain it all off again and every time I do this the water heater has loads of air in it. So Its back to the drawing board Im afraid.
Sir Roger

 

[RayS]

I've been following the discussion with interest, having similar problems with a Whale on board pump.
Fitting a surge damper appeared to make no difference.
Making the pipework more figid by using cable ties to pull hot and cold lines - both semi rigid pipe- together helped considerably, as did the same treatment to the connections to the handbasin tap. The connections to this are metal braded flexible type and were installed with the slack left loose .

 

[ProfJohnL]

The more recent posts are serving to amplify the point I made in my last post. Whilst I'm sure all the comments have been made with the best intentions, the problem has not moved on, and even the actual issue has not been fully understood. Is it air in the pipes or is it vibration? Perhaps it's both, or something else entirely.

I know using a professional costs and is like admitting defeat, especially when water systems are theoretically simple and straightforward, but getting pro help should remove the uncertanties, any get it fixed quickly.

 

[SirRogerFFS]

Prof John L and everybody who has contributed to my problem, It is appreciated but I must say to clarify, the problem has only happened when my Flojet pump died and the only replacement from my dealer was a shurflo.Now since fitting the pump I have this knocking from the which I now believe is a two fold issue. The Flojet pump never had this problem and was quiet apart from one sort of clunk if you like when you turned a tap off.Way back in this thread I did say I had concerns that whilst trying to cure this problem we found that the water heater had loads of air in it,Im not a complete novice this is telling me that the noise created from the pump is air hence the non return valves fitted to the pump which more or less cured the cold side . I hope I have made this a little clearer. I cant thank you all enough for showing interest in this issue

 

[chrisn7]

Here again!
-I feel it would be better not to keep draining the system down each time you try a solution. Having the system 'full' potentially removes a variable.
-Vibration. It might pay you to check that each radiator is properly mounted to the wall with the required number of screws. I found one in my van with no screws at all, and 2 others loose with only a couple of screws in place. All could knock against walls
-I might have missed it in the posts, but have you checked the pressure switch settings?. Our old Whale system used to pulse furiously sometimes until the switch was reset
-The one way valve - as this is new work done, have you re-checked it for proper installation? Its easy for new works to create problems as well as solve them

 

[SirRogerFFS]

Wow Chrisn7 this thread is going well page 3.There was never a problem until this shurflo pump went in. Im confident its an air problem . I think I may well l have been close to a cure at the weekend but I was cold and feeling Ill I said sod the caravan and went home . Im still suffering so I hope by the weekend it will be a different story.
Thanks again Sir Roger

 

[McBoaty]

I hate to ask..... but was there ever a fix to this issue? I have recently fitted a new like for like Shurflo pump to replace a failed Shurflo pump. The two pumps are exactly the same type/fitting but due to obscelesence the new pump is slightly higher rated in terms of flow. My problem is that after being left unused for a while the new pump operates normally when switched on but creates a knocking noise which continues after the tap is turned off. I have a switch on my pump so can switch off 12v supply to stop the noise. The pump operates like this for a while but then after some use it then works quite normally with no noises until the next time that the pump is unused for a while & then same pattern repeats....have checked installation etc but only physical difference is the pump itself......aaargh! 80)

 

[ProfJohnL]

I hate to ask..... but was there ever a fix to this issue? I have recently fitted a new like for like Shurflo pump to replace a failed Shurflo pump. The two pumps are exactly the same type/fitting but due to obscelesence the new pump is slightly higher rated in terms of flow. My problem is that after being left unused for a while the new pump operates normally when switched on but creates a knocking noise which continues after the tap is turned off. I have a switch on my pump so can switch off 12v supply to stop the noise. The pump operates like this for a while but then after some use it then works quite normally with no noises until the next time that the pump is unused for a while & then same pattern repeats....have checked installation etc but only physical difference is the pump itself......aaargh! 80)

It is quite normal for these pumps to run on momentarily after the taps are closed. They run to re-pressurise the entire water system. It will especially happen if you have used any hot water becasue the hot tank is designed to contain an air space which is to allow space for the water to expand into when its heated, the more dense cold water needs to recompress the air cap which might take a few seconds.

Another effect that can arise, is the pipe work is plastic, and is not entirely ridged. It when its pressurised it can stretch just a tiny bit, and it will continue to do this over a few minuets, The hot pipe work will do it a bit more when its warm I'm not talking a bout much, but the small increase in volume might be enough to drop the pressure and turn the pump to turn on momentarily to re-pressurise the system.

However, you tell us you have been turning your pump control off to alleviate the noise, which prevents the pump from automatically maintaining the pressure in the system. I do wonder if you have a small leak somewhere. Obviously I cannot tell, but do you have any unexplained drips anywhere?

It could be a problem with the water heater. Carver Cascade2 water heaters are prone to suffering damage to their inlet non return valves, where the formation of frost can dislodge and compromise the shuttle in the valve. (This is why draining the system for winter storage is so important.) A faulty NRV can restrict in inflow of cold water into the appliance making it slow to fill, but it can also allow water to flow back into the supply pipe work, however in a pressurised system the standing pressure in the pipe work should prevent it, but as you have been turning the pump off, the pressure is not there. This scenario also needs there to be a leak to allow the volume of water to escape. The Valve can also be compromised if an inline water filter has burst its carbon granule containment

Check for signs or a water leak throughout the system. Check the NRV to the water heater