No water coming through from shower pump

[glenintheuk]

I do hope someone can help! I have had a new bathroom fitted, as part of this I opted for a thermostatic mixer shower with both a fixed and mobile shower head. This is powered by a Shower mate 2.0 Eco pump. When I turn the shower on, we sometimes get a full supply, however more often than not we get a constantly intermittent pulsing of water, and occasionally we get absolutely nothing, not even water, and the pump doesn't even kick in! If I leave the supply switched on the pump eventually kicks in and we get intermittent or full supply. It seems to be worse the hotter the shower is.

The cold water tank is in the loft, about 2 metres above the top of the hot water cylinder, which is in the airing cupboard, on the same floor as the bathroom in question. The pump is level with the bottom of the hot water cylinder. The pipe work goes from the pump, up through the ceiling, through the loft, and drops back down to the shower.

One thing, the hot water supply to the pump is via a t-piece next to the hot water cylinder. Someone has told me this should really come via a flange (Essex?). Is this more than likely the reason for my problem please?

 

[footprints]

Sounds like it might be an air lock in the loft on the hot supply, did the installer fit any means of bleeding air from the pipe where it passes across the loft?
Regards
footprints

 

[glenintheuk]

Thanks for the reply. He fitted a manual service valve in the loft, which he used once when we were first having problems. Naturally we can't go up there every time we get the problem. Are there are ways of fitting automatic bleeding valves (sorry for the languauge!)

Sounds like it might be an air lock in the loft on the hot supply, did the installer fit any means of bleeding air from the pipe where it passes across the loft?
Regards
footprints

 

[kvsalamander]

good afternoon,

most pumps will require a certain amount of natural flow to lift a flow switch and keep it lifted.

depending on the manufacturer of the pump there should be minimum flow rate - if it drops below this the floats will lift up and down causing this puling effect.

it could even be a case that the shower cartridge is getting a bit too restrictive for the pump.

i would attach a couple of hoses to the outlets of the pump and run the pump into a bucket and see how it works.


cheers

 

[footprints]

Hi,There are auto bleed valves designed for central heating but I'm not sure they would be ideal.
The pressure from the pump I assume would be 2 bar plus the small head from the tank, most sealed heating systems which the bleed valves are designed for run at just under 1 bar, but if you check the spec of the auto air vent it may be ok. however I suspect it would soon scale up. A heating system contains inhibitors and anyway after a few firings the scale from the water is deposited in the system so no more will be produced. The shower water however will be fresh each time and so deposit scale each time it's operated.
Mainly though it's a bit of a bodge the real answer is to get the installer back to try and find a solution.

Many shower manufactures no longer specify an Essex flange simply saying you can come off the top of the cylinder providing you immediately drop down to the pump. The point of an Essex flange is firstly it uses a dip pipe to take water from the centre line of the cylinder to give an even temperature and secondly it prevents air bubbles which tend to form on the inside walls of the cylinder being pulled into the pump. It's not normally a problem but it may be in your case that an essex flange might help if the air is getting in by that route. unfortunately the only way to see is to try it and that's going to mean more expense with no guarantee of success.

Best wishes,
footprints

 

[glenintheuk]

Many thanks, it looks like I might have to give it a go. I do have a replacement 3 bar pump, would this be likely to improve the situation at all? Thanks. Glen[/code]

 

[footprints]

If it’s a straight swap no harm in trying the 3 bar pump, there is a chance that if air is trapping in the loft pipe run the bigger pump might shift it, on the other hand any air passing through the pump may lead to cavitation (air and water beaten into a froth) reducing the force of the pump, but no harm in trying it if it works ok fine, if its noisy or pressure is not improved take it out, as long term cavitation can damage the pump impeller.

Its worth trying one thing to see if it clears the problem though, take the shower head off let the hose hang down as low as possible, run the shower full on and move the temperature selector from hot to cold several times, crossing your fingers and using a series of expletives at the same time is optional!

Is there any reason you can't get the installer back? Would seem better than going to expense and trouble yourself.

Regards,
footprints

 

[glenintheuk]

Hi footprints, thanks again for your help. The pump wouldn't be a straight swap as such as the pipe work would need to be altered (different make). I have tried without the shower head on, just the hose running, seems okay most of the time, but this is the problem, it doesn't always happen, its the worst type of fault, an intemittent one! However when I run just the hose I must say its normally fine. I had a lot more problems with the fixed head too until I took out the restrictor inside the head, this seemed to improve things, although its far from 100%. Is there any way of improving the intake of air situation?

If it’s a straight swap no harm in trying the 3 bar pump, there is a chance that if air is trapping in the loft pipe run the bigger pump might shift it, on the other hand any air passing through the pump may lead to cavitation (air and water beaten into a froth) reducing the force of the pump, but no harm in trying it if it works ok fine, if its noisy or pressure is not improved take it out, as long term cavitation can damage the pump impeller.

Its worth trying one thing to see if it clears the problem though, take the shower head off let the hose hang down as low as possible, run the shower full on and move the temperature selector from hot to cold several times, crossing your fingers and using a series of expletives at the same time is optional!

Is there any reason you can't get the installer back? Would seem better than going to expense and trouble yourself.

Regards,
footprints

 

[glenintheuk]

Also, forgot to say, the installer has become incredibly difficult to contact!!

Hi footprints, thanks again for your help. The pump wouldn't be a straight swap as such as the pipe work would need to be altered (different make). I have tried without the shower head on, just the hose running, seems okay most of the time, but this is the problem, it doesn't always happen, its the worst type of fault, an intemittent one! However when I run just the hose I must say its normally fine. I had a lot more problems with the fixed head too until I took out the restrictor inside the head, this seemed to improve things, although its far from 100%. Is there any way of improving the intake of air situation?

If it’s a straight swap no harm in trying the 3 bar pump, there is a chance that if air is trapping in the loft pipe run the bigger pump might shift it, on the other hand any air passing through the pump may lead to cavitation (air and water beaten into a froth) reducing the force of the pump, but no harm in trying it if it works ok fine, if its noisy or pressure is not improved take it out, as long term cavitation can damage the pump impeller.

Its worth trying one thing to see if it clears the problem though, take the shower head off let the hose hang down as low as possible, run the shower full on and move the temperature selector from hot to cold several times, crossing your fingers and using a series of expletives at the same time is optional!

Is there any reason you can't get the installer back? Would seem better than going to expense and trouble yourself.

Regards,
footprints

 

[footprints]

You really need to confirm the problem is air in case I‘m leading you down the wrong route, you say the installer fitted a manual vent in the loft to sort out the problem does that still cure the trouble when it’s vented?
The other possibilities are, too little static head to operate the flow switch on the pump as kvsalamander suggested, although if your pipes run across the loft floor the water level in the tank will be about 2 ft above that which is usually enough unless you have very convoluted or small bore pipe runs. The outlet of most pumps is 22mm it’s best to run this as far as possible before dropping down to 15mm for the last couple of feet if the run is a low head one.
The flow switch could be faulty, a service valve may not be fully turned on, or simply something else taking tank water at the same time WC, sink, washing machine etc.

 

[glenintheuk]

You really need to confirm the problem is air in case I‘m leading you down the wrong route, you say the installer fitted a manual vent in the loft to sort out the problem does that still cure the trouble when it’s vented?
The other possibilities are, too little static head to operate the flow switch on the pump as kvsalamander suggested, although if your pipes run across the loft floor the water level in the tank will be about 2 ft above that which is usually enough unless you have very convoluted or small bore pipe runs. The outlet of most pumps is 22mm it’s best to run this as far as possible before dropping down to 15mm for the last couple of feet if the run is a low head one.
The flow switch could be faulty, a service valve may not be fully turned on, or simply something else taking tank water at the same time WC, sink, washing machine etc.

Many thanks to everyone for their posts. In response to suggestions,:

As the problem is intermittent - it doesn't happen every time the shower is turned on and sometimes kicks in after a few minutes - then would I be right in thinking it cannot be due to a faulty shower cartridge, or a faulty pump (it was brand new and unused) as it sometimes works fine?

Would I be right in assuming that the best first option would be fitting an Essex flange?

Cheers for any further comments
Glen

 

[footprints]

I was waiting to see if anyone else had a suggestion but as no one has posted I’m afraid it’s me again!

As you say the shower mixer itself will either work or not. a faulty flow sensor in the pump can be intermittent, but in the long run there is no substitute for someone who is familiar with showers looking at it. An Essex flange won’t do any harm but it’s not something you can just bolt on. The cylinder needs to be drilled and fitting the components working through the new hole can be a bit of a fiddle.

Why not contact the pump and or shower manufacturer and see if they have a service agent in your area. It may cost a bob or two but in the long run may be better than just calling another plumber chancing he can sort it and perhaps spending a fair bit of cash in the process to no avail.
Regards,
footprints

 

[seco services]

What is the mixer make/model ?
What size is your pipework to/from pump ?

Sounds like you have a flow issue on the boarder line of a neg head situation.

What natural flow l/pm are you getting from each side with pump off ?

 

[glenintheuk]

Thanks for the replies once again.

Used it myself yesterday for 5 minutes or so, with no issues at all - very frustrating!

Pipework appears to be 22 mm to and from, reduces to 15mm near the pump (to fit the inlet valves) and reduces in the loft above the shower mixer to 15mm for the same reason. Mixer is a Triton Capella.

Not sure about the natural flow near the pump, seem to get a steady flow form the mixer most of the time, with the pump turned off, but have had occasions with no flow.

Cheers
Glen