Power Shower Woes

11 Jul 2011
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United Kingdom
I have installed a salamander ESP75 CPV pump to a Gledhill Envirofoam Stainless Steel SE36X18IND Hot Water Water Cylinder.

The cold feed I have taken from the CWS via 22mm pipe.
The hot is from the shower take off point (similar to essex flange) which is fitted as std. to the cylinder.

It is a Neg. head situation with the shower head being a foot higher than the base of the Cold Water Storage.

All the suction side of the pump is 22mm and the pressure is reduced to 15mm shortlay after leaving the pump.

Plumbed up, installed, flushed through, switched pump on and turned on shower for the first time....It ran lovely, no issues with it.

I turned the shower off and the pump did not want to stop, it makes horrid noises. I turned it off at the wall.

I now switched it back on and the thing doesn't work at all.

To me the mechanism/sensor that senses the pressure build up seems to be faulty. Unfortunately the thing is out of warranty.

Does the installation sound ok and does it sound like a buggered pump?

Help please!!
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Where is the pump located in relation to the cws & hws tanks? How long is the 22mm feed pipework? You say it’s fed from a pre-fitted flange similar to an Essex flange, an Essex has an internal upswept pipe to avoid drawing air bubbles, are you sure your fitting has this & is not just an ordinary tank flange? What is the pipe work route from the pump to the shower mixer & onto the head, ie up & over loops?

It sounds as though the pump may have become air locked, have you tried bleeding it?

If you’ve only just installed the pump how come the warranty is out, even the standard warranty is 2 years! :confused:
Pump has been installed elsewhere before with no issues...but is 3 odd years old.

I am told that the shower take off flange is similar to an Essex flange by Gledhill. - It is formed into the tank when it is manufactured.

The pump is next the the HWS on the floor, and the CWS is about 1.5metres directly above it - al I have I am in a ground floor flat.

The pipes are routed through the wall, through a boxed in area, under the back of the bath and the up to the thermostatic mixer. - There are no massive changes in height.

I ran the pump without the mixer attached....The performance was great until I tried to turn it off!!
The installation sounds OK so unsure why it’s suddenly given up the ghost. I assume you mean you ran it without the showerhead attached which would make no difference; I don’t see how you could run the pump without the mixer attached!

A possible cause could be failure of the negative head pressure vessel as you suggest, possibly why the pump wouldn’t turn off initially & now won’t start either. Could be debris has got inside one or both of the pump impellers, I assume the water inlet filters are in place?

I would try bleeding it again & check the motor & impellers still turn freely but I’ve no idea how to check/test the pressure vessel & flow switches are still functioning; a phone call to Salamander technical may help.
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I have examined the pump vanes and and all seems ok....

One thing I have noticed which I think is very strange is:

The pressure vessel seems to vent bubbles out of the outlets?

The schrader valve on the pressure vessel squirts out water when the pin is depressed!

The cold outlet from the pump is quite warm.

I thought (perhaps incorrectly) that the pressure vessel had a diaphragm fitted and the bladder should be pressureised to 20 psi?

Am I correct?

Has the diaphragm got a hole in which is allowing hot and cold sides to mix, making the pump seem like its cavitating by mixing the air in and confusing all of the sensors what is going on?

Can these pressure vessels be replaced and if so how can a new one be sourced?
As I said, I don’t have any experience of fault finding NH pressure vessels I just fit new pumps, install & plumb new shower installations. Try the Sally technical dept. they should also be able to advise you regarding spares.

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