Sturat Turner Pump not working

ChristyFM

Stuart Turner Pumps. We have just recently (2 months ago) had a power shower installed it's a Stuart Turner Pump ST 66 Contract 1.5 bar. It is fitted next to the hot water tank to the wooden slatted floor and it is quite noisy!

Majority of the time it has worked well. Once or twice the shower would not work. There would be silence from the pump and not a drop of water from the shower head. (We have no problems with water supply.) However, this week it just didn’t operate. We asked the plumbers to call back, they and said it was lime scale (we don’t have that problem usually) blocking the pipe. It was working when they were in the house but that evening it wasn’t. They are on the way back today to fix it again saying this time they will replace the bar in the shower. (This begs the question if that was the problem then why wasn’t it fixed yesterday?).

Has anyone any suggestions as to what the problem might be and how it can be resolved?


Regards

cnocbui

Firstly, get a different plumber.

I live in a very hard water area, I have a ST pump, and I don't think there is any chance limescale is going to affect a pump in two months. It hasn't affected mine in over two years.

The "not a drop of water from the shower head" is a clue.

The pump is turned on by a flow switch, which detects water flowing through the pump when you turn a tap on. The switch requires a certain minimum flow rate to operate. If there is not enough natural flow then the switch might not operate.

The ST 66 appears from the ST website to be a 'positive head' pump, in other words it needs the water supply feeding it to have a bit of pressure - such as would be provided by a gravity fed system with a tank in the attic.

If you turn the shower taps on, some water should always flow, even if the pump is disconnected from the electricity. If you really are not getting any water out of the shower head, when you open the tap, then a lack of water flow is probably the problem since the flow switch will not work and turn the pump on.

The flow switch works by there being a little float inside the pump with a magnet in it. When you turn on the tap, this float/magnet rises up a tube due to the flow of water. The actual switch is on the outside of the tube and it senses the magnet through the walls of the tube and signals the pump to turn on. When you turn off the water, the water stops flowing and the magnet sinks back down and the switch turns off.

A simple little test you could do is to turn on the shower taps, get a magnet and bring it close to one of the two flow switches - there is one each for the hot and cold water parts of the pump - and see if the pump turns on and water starts coming out of the shower head.

This is perfectly safe to try and there is no chance of an electric shock.

There is a parts diagram for your pump here:

http://www.stuart-turner.co.uk/where-to-buy/spares-finder/46435/10

Click on the little picture showing the pump parts to see a larger image.

The flow switches are the little boxes with wires coming out of them labeled 5.

If the pump works and lots of water comes out of the shower head, you will know there is nothing wrong with the pump and that there is no blockage or need for a new 'bar'

If the pump does turn on but little water comes out, you will know that you might have a blockage somewhere.

If the pump doesn't turn on, it may have a problem, the magnet may not be strong enough - but the switches are very sensitive (try both) - or the pump isn't getting power due to a tripped circuit breaker etc.

Let us know how you get on.

items

Sounds like they (plumbers) are going to lower the shower bar. Shower head could be to high, no movement of water to activate pump when shower valve opened. If they lower shower bar and all works you can leave be, provided shower head is not to low, if still no joy, you might need a negative head pump fitted.

ChristyFM

Thanks for the comprehensive assessments - Wow! Sometimes I feel like getting another plumber. However, he has been paid and it is under guaranteee - for what it is worth. Anyway, I have learnt that the plumber has fiitted a new shower as he said that the value in the shower was not working.(Opening up) So it is working at the moment but time will tell.
Thanks again for all your suggestions.

items

ChristyFM wrote: »

Thanks for the comprehensive assessments - Wow! Sometimes I feel like getting another plumber. However, he has been paid and it is under guaranteee - for what it is worth. Anyway, I have learnt that the plumber has fiitted a new shower as he said that the value in the shower was not working.(Opening up) So it is working at the moment but time will tell.
Thanks again for all your suggestions.

Christy, have you an exposed shower valve? or valve behind tile? If valve behind tile it would be a messy job replacing shower as tiles would have to come off, back on again re grouted etc, you might have had shower internals replaced. Reason I say this, I've never heard of a brand new shower valve not working in all my plumbing years.

Sometimes plumbers say they've done one thing but do something else, everything might be above board and good plumbers but just curious to know if shower head is now lower than before? Has shower rail been lowered?

ChristyFM

Hi
Strange one alright. He didn't lower the shower bar and it is not covered by tiles. Although it worked last night for a moment it didn't start until we reduced the temp to cold and then it started. If that is what you have to do to get it to work then that's okay as long as it continues to work. I'm still half expecting a call from home saying its not working anytime in the near future though.

Thanks

items

Somethings not right with shower pump, pump should come on if a tap or shower is opened regardless of water temperature, ST pump only detects water movement and water pressure, no temperature sensors fitted.

If pump starts to give trouble again, if possible take a few pictures of pump and where pump connections lead to, might be a pipe work problem.

cnocbui

Wouldn't this indicate there is an issue with just the flow from the hot water cylinder being inadequate?

By setting the tap to cold (assuming mixer) there is enough flow to activate the flow switch on the cold side of the pump, then once the pump is started, the setting can be altered to hot and will continue to function till the shower is turned off.

I suspect a qualpex pipe in the attic or somewhere is bowing up so part of it is above the cold tank level. I know mine wanted to bow up and had to be fastened down to overcome their natural urges.