# Poor water pressure



## 116005 (Aug 26, 2008)

I know this subject has been covered a number of times but..... 
On 2002 B574 I have installed a new pump and now cannot get decent pressure on the hot and cold water systems. Have tried the suggested options - switching around wires on pump , fitting new non return valve on tank outlet , checking connections / leaks , running taps open, full drain down etc. 
The problem persists - no toilet flush , poor and intermittent pressure at taps. 
Am I missing something obvious ? There isn't a valve in the system that I haven't found is there ? The advice I have received is that it must simply be an air lock , but if so it must be one which reoccurs with each system fill. Is there a specific place where an airlock of this nature frequently occurs, or does anyone have a suggestion of what to try next ?


----------



## JockandRita (Jun 1, 2005)

chalten said:


> I know this subject has been covered a number of times but.....
> On 2002 B574 I have installed a new pump and now cannot get decent pressure on the hot and cold water systems. Have tried the suggested options - switching around wires on pump , fitting new non return valve on tank outlet , checking connections / leaks , running taps open, full drain down etc.
> The problem persists - no toilet flush , poor and intermittent pressure at taps.
> Am I missing something obvious ? There isn't a valve in the system that I haven't found is there ? The advice I have received is that it must simply be an air lock , but if so it must be one which reoccurs with each system fill. Is there a specific place where an airlock of this nature frequently occurs, or does anyone have a suggestion of what to try next ?


Hi Chalten,

You could try shaking the submerged pump to rid it of any air in the casing. I once had to do this in a bucket of water prior to resubmerging the pump back into the tank. Is it a Reich twin impeller? Most pumps have a small hole at the top of the casing to allow air to escape and assist priming. If all was well before the old pump went belly up, I'd suspect an air lock with the new pump.

I just hope that your poor pressure isn't as a result of a leak somewhere in the pipeline. 8O

Good luck with it,

Jock.


----------



## Pudsey_Bear (Sep 25, 2008)

Hi, not exactly the pump miester, but ours had a membrane in the pipe fitting, could yours be the same? also it can be quite easy to kink the feed pipe on some models.


Kev.


----------



## JohnsCrossMotorHomes (Jul 21, 2007)

Check the water pressure at the nearest 'join' to the pump. if it is ok there. work 'forwards'

Peter


----------



## JeanLuc (Jan 13, 2007)

Some thoughts - and forgive me if this seems like questioning the bleedxxg obvious.

1. I thought the non-return valve was built into the output of the Reich pump. (See the bit sticking up in the picture below.) If you have fitted another one, are the two working against each other?

2. I assume the pump is running and so trying to push water somewhere?

3. There are two water pipes from the tank. One is the feed and the other is the return. The pump runs at constant pressure and any 'unused' water (e.g. tap only just on) comes back to the tank. I suppose there is no chance you have switched these pipes in connecting the new pump?

Hope you sort it out.

Philip


----------



## pieterv (Feb 3, 2009)

You might have already checked this when looking for leaks but my problem was that the connector the pump connects to in the lid of the tank (on the inside) was partially cracked, so part of the water the pump delivered never made it out of the tank.

Pieter


----------



## 116005 (Aug 26, 2008)

*Poor Water Pressure*

Many thanks for replies on this. I'm still at a loss at the moment. Now getting no flow from any taps. When I turn on a tap with the drain taps open there is a flow out of the system suggesting there is water in the pipes generally, just not enough pressure to push it up through the sink taps. Perhaps this also suggests air lock not the cause.
I am thinking the pump ( Hymer standard part - Tandem 19l/ 1.4 bar ) may not be creating enough pressure and could simply be faulty or blocked in some way. How do I know what is enough pressure though ? The stream out of the tank outlet pipe looks quite strong. Am I right in thinking that it should move 19 litres in one minute from where it sits in the tank ie if I connect the out pipe to a piece of hose and empty into a bucket it will indeed take one minute to produce this amount of water ?
Looking very much that a professional is going to be needed here !!


----------



## teensvan (May 9, 2005)

Hi.

We had a similar problem to yours and I also bought a new pump, as we kept getting air locks When it was connected up in the tank the new pump was worse than the one I took out. I removed the pump and bench tested it in a large bucket of water and it still had a very poor outlet pressure, so I took it back and got my money back. I then bench tested my old pump and it gave a good output of water. When the old pump was put back in it worked perfect. We still get an occasional air lock so I remove the outlet pipe where it comes out of the tank and get Ann to start the pump up via the tap. The pump pumps water into a small bucket for 2 seconds and then we reconnect the pump , and it works fine again.

steve & ann. ------------ teensvan


----------



## JockandRita (Jun 1, 2005)

*Re: Poor Water Pressure*



chalten said:


> Am I right in thinking that it should move 19 litres in one minute from where it sits in the tank ie if I connect the out pipe to a piece of hose and empty into a bucket it will indeed take one minute to produce this amount of water ?
> Looking very much that a professional is going to be needed here !!


Indeed, that is what the pump should be capable of.

If the strainer isn't blocked, you don't have a leak, and there are NO air locks, I suggest removing the outlet pipe from the pump and with each tap opened and closed in slow succession, try sucking back through the pipe and into a bucket, being careful not to swallow anything that MAY be dislodged.

Reconnect, prime the pump, and try again.

The best of luck. :?

Jock.


----------



## 116005 (Aug 26, 2008)

*Poor Water Pressure*

Again many thanks for advice.
Some progress - removing pump , shaking again and running in a bucket it produced a better flow and taps / shower OK . A day later flow not quite so good , but still working. No toilet flush though , but I always suspected this might be a different issue anyway.
Will get a specialist to look it over for any other faults.


----------



## JockandRita (Jun 1, 2005)

*Re: Poor Water Pressure*



chalten said:


> Again many thanks for advice.
> Some progress - removing pump , shaking again and running in a bucket it produced a better flow and taps / shower OK . A day later flow not quite so good , but still working. No toilet flush though , but I always suspected this might be a different issue anyway.
> Will get a specialist to look it over for any other faults.


Hi again Chalten,

If the flow is not so good a day later, I would definitely suspect a leak in the system, ie, air getting in, and possibly water getting out, as it doesn't seem to be holding the pressure. 
Re the toilet flush....it is usually the last in the line. The last time I had a poor toilet flush, I changed the wires over at the pump, and hey presto, but you did mention you tried that, at the beginning of your thread.

Sorry to read that a DIY fix doesn't appear to bring a cure to your problem.

Incidentally, have you traced the pipework and joints from the pump to all outlets, to check for seepage. We did have a problem with loose jubilee clips at one time, causing a pipe to blow off the tap inlet stem. Most others needed tightening too.

Regards,

Jock.


----------

