Hello All

I have just realised that my pump which powers my thermostatic shower
cycles on and off when I turn the hot water tap off in the bathroom
(haven't tried any others) The pump only powers the shower and is fed
from an essex flange installed into the HW cylinder. This cycling also
happens when the shower thermostat it set to a certain temperature and
the shower valves are off, see other postings!

I'm guessing here that there is something wrong in the way I installed
the Essex flange or there is air somewhere in the system?

Anyone have any ideas on this, surely this should not happen.

TIA

Cheers

Richard

You need a 22/28mm check valve in the output side of the pump IMO. The 
cycling is caused by water surging backwards and forwards through the 
flow valve. This is another indication that the input to the pump (and 
possibly also the hot water tank) is inadequate, and the pump is trying 
to suck water from the hot water tank air venting system.

	Regards
	Capitol

Hello

Is this the same as a non return valve?

What is the hot water tank air venting system? I have a vent pipe that
exits the top of the HWC which goes to the Cold water tank (The One
that feeds the HWC).

Cheers

Richard

In an earlier contribution to this discussion,
r.rain@btinternet.com   wrote:


> Hello
>
> Is this the same as a non return valve?
>
> What is the hot water tank air venting system? I have a vent pipe that
> exits the top of the HWC which goes to the Cold water tank (The One
> that feeds the HWC).
>
> Cheers
>
> Richard


I presume 'One' refers to tank and not pipe!

[You should have a vent pipe from the top of the HW cylinder which goes up
and over the top of the cold water tank. You should *also* have a feed pipe
from the bottom on the cold water tank, feeding into the *bottom* of the HW
cylinder.]

Going back to the original question, what is supposed to trigger your pump -
is it flow, or pressure?
-- 
Cheers,
Set Square
______
Please reply to newsgroup. Reply address is invalid.

Flow is supposed to trigger it, I think. I dont understand why by
turning my hot water taps off should force the pump to cycle. I thought
the whole idea of having a flange was to keep these things seperate so
they would not interfere. Damn shower has given me soooo much grief and
everyone I speak to has a different opinion. Should of stuck with a
power shower all in one jobby like I ripped out...........

I'm waiting for another call back from the pump people Stuart Turner at
the moment

Cheers

Richard

wrote in message 
news:1126003310.164693.67660@g44g2000cwa.googlegroups.com...

> Flow is supposed to trigger it, I think. I dont understand why by
> turning my hot water taps off should force the pump to cycle. I thought
> the whole idea of having a flange was to keep these things seperate so
> they would not interfere. Damn shower has given me soooo much grief and
> everyone I speak to has a different opinion. Should of stuck with a
> power shower all in one jobby like I ripped out...........
>
> I'm waiting for another call back from the pump people Stuart Turner at
> the moment
>


1. Is the pipework for the pump "elastic" i.e. plastic?
2. Is the feed pipe from the cold water header into the cylinder restricted 
in any way?
3. At the end of the day is it really important that your pump pulses or 
not?
4. Can you not incorporate an interlock with the shower room light or fan?

In an earlier contribution to this discussion,
r.rain@btinternet.com   wrote:


> Flow is supposed to trigger it, I think. I dont understand why by
> turning my hot water taps off should force the pump to cycle. I
> thought the whole idea of having a flange was to keep these things
> seperate so they would not interfere. Damn shower has given me soooo
> much grief and everyone I speak to has a different opinion. Should of
> stuck with a power shower all in one jobby like I ripped
> out...........
>
> I'm waiting for another call back from the pump people Stuart Turner
> at the moment
>
> Cheers
>
> Richard


The Essex flange ensures that hot water is drawn from a point some inches
below the top of the hot cylinder - thus preventing air from being sucked in
from the vent pipe.

It sounds as if something is causing a small amount of flow to occur at the
point where it is detected by the flow switch. Does the pump cycle
continuously once it starts? What are the approx on and off times?

Where does the cold feed for your shower pump come from?

Does the problem still happen if you turn the bath tap off very slowly
rather than suddenly?

Hopefully, the pump is on a separate electrical circuit with its own
isolator switch - in which case, as a short term solution, you can turn it
off when not required.
-- 
Cheers,
Set Square
______
Please reply to newsgroup. Reply address is invalid.

John wrote:

>  wrote in message
> news:1126003310.164693.67660@g44g2000cwa.googlegroups.com...
> > Flow is supposed to trigger it, I think. I dont understand why by
> > turning my hot water taps off should force the pump to cycle. I thought
> > the whole idea of having a flange was to keep these things seperate so
> > they would not interfere. Damn shower has given me soooo much grief and
> > everyone I speak to has a different opinion. Should of stuck with a
> > power shower all in one jobby like I ripped out...........
> >
> > I'm waiting for another call back from the pump people Stuart Turner at
> > the moment
> >
>
> 1. Is the pipework for the pump "elastic" i.e. plastic?

Yes it is

> 2. Is the feed pipe from the cold water header into the cylinder restricted
> in any way?


Haven't checked that but would hope not, I dont seem to have any other
problems


> 3. At the end of the day is it really important that your pump pulses or
> not?


Not when the hot water taps are turned off, this just happens the once.
What  is more concerning is that this happens when the thermostatic
control on the shower is set to hot and both flow vlaves are off. In
this case sometimes the cycling won't stop until I move the dial to
another temperature setting. It may just be that the cycling would
eventually stop but it really shouldn't be doing this surely.


> 4. Can you not incorporate an interlock with the shower room light or fan?


No

Thanks for your response

Cheers

Richard

Set Square wrote:

> In an earlier contribution to this discussion,
> r.rain@btinternet.com   wrote:
>
> > Flow is supposed to trigger it, I think. I dont understand why by
> > turning my hot water taps off should force the pump to cycle. I
> > thought the whole idea of having a flange was to keep these things
> > seperate so they would not interfere. Damn shower has given me soooo
> > much grief and everyone I speak to has a different opinion. Should of
> > stuck with a power shower all in one jobby like I ripped
> > out...........
> >
> > I'm waiting for another call back from the pump people Stuart Turner
> > at the moment
> >
> > Cheers
> >
> > Richard
>
> The Essex flange ensures that hot water is drawn from a point some inches
> below the top of the hot cylinder - thus preventing air from being sucked in
> from the vent pipe.
>
> It sounds as if something is causing a small amount of flow to occur at the
> point where it is detected by the flow switch. Does the pump cycle
> continuously once it starts? What are the approx on and off times?


When the hot water taps are turned off it only cycles once on and then
off for 1 second in duration. Other times when it happens after using
the shower it will continuously pulse on and off like every second or
so and it seems a steady rhythm until I move the temperature gauge when
it will stop.


>
> Where does the cold feed for your shower pump come from?

>From its own cold water tank, it doesn't feed anything else.

>
> Does the problem still happen if you turn the bath tap off very slowly
> rather than suddenly?


Not sure will have to test that one out.


>
> Hopefully, the pump is on a separate electrical circuit with its own
> isolator switch - in which case, as a short term solution, you can turn it
> off when not required.


It is but it's in the loft, which is where the HW cylinder, Cold tank
and pump is located. I decided against one of those horrible string
pulls.

Cheers

Richard


> --
> Cheers,
> Set Square
> ______
> Please reply to newsgroup. Reply address is invalid.

r.rain@btinternet.com wrote:

> Hello
> 
> Is this the same as a non return valve?
> 

	Yes. Screwfix 11124. There is probably some air being released/trapped 
in the pipework, or a degree of expansion/contraction in rubber 
connectors, so when you turn off the water flow, some water runs 
backwards through the pump, over does the correction, then the water 
flows back through the pump in the normal direction, causing the pump to 
turn on. Then the cycle repeats. Another solution is to adjust the flow 
valve to make it less sensitive. This problem normally occurs in the hot 
supply, so a check valve in the pump hot output usually prevents the 
problem from happening.

	Regards
	Capitol

The pump expert thinks this too, he suggested fitting a bleed valve in
the pipe work, never seen these before only in rads.
He also thinks there is a problem with the shower valve too. I have the
shower engineer coming Friday so hopefully he can get it fixed for me.

Thanks for all your help

Cheers

Richard

The pump expert thinks this too, he suggested fitting a bleed valve in
the pipe work, never seen these before only in rads.
He also thinks there is a problem with the shower valve too. I have the
shower engineer coming Friday so hopefully he can get it fixed for me.

Thanks for all your help

Cheers

Richard

The pump expert thinks this too, he suggested fitting a bleed valve in
the pipe work, never seen these before only in rads.
He also thinks there is a problem with the shower valve too. I have the
shower engineer coming Friday so hopefully he can get it fixed for me.

Thanks for all your help

Cheers

Richard