Electric Shower Pressure Weirdness

[jkn]

Hi All We have a Triton electric shower, fairly high end as these things go (don't start...) 10 years old or so. It has a 'low water pressure' mode; when in this mode an LED flashes and the water will not heat.

For a long time there has been an intermittent 'situation':

- I turn the shower on in the morning

- after a seconds, the low water pressure light starts flashing

- I flush the loo; after a couple of seconds the cistern starts filling and the light goes out; the shower operates normally

- when the cistern has filled, the shower may or may not return to 'low pressure' mode

ie. it seems to be more of a *high* water pressure situation, alleviated for a while by flushing the loo.

Any thoughts what might be happening here?

Thanks J^n

[fred]

In article , jkn writes

These things usually have a fine mesh strainer on the inlet, check for blockages, clean and refit.

Any other flow restrictions on the inlet would do the same thing or possibly a faulty solenoid inlet valve but check the obvious first.

Alternatively, if the flow coming from the shower head is normal then look at the low pressure switch. The cistern business just means that the low pressure indication is borderline and that any supply pressure fluctuation (eg cistern fill on/off) is enough of a blip to flip it.

Have a play too with it on the cold setting (if there is one) to see what the flow is like.

Watch yourself on the electrics.

[jkn]

but my intended point is that the 'low pressure' fault is rectified by situations which would seem to cause (further) reduced pressure, not those that might raise it.

This is a fair point, I guess - thanks.

Indeed. Luckily the 'power block' is situated a distance from the shower head...

Cheers J^n

[PeterC]

This might be a red herring, but I've observed that when the flush is operated when the shower is on the flow from the shower seems to increase slightly. The change when the cistern is full isn't really noticeable - perhaps because it's gradual. My 'thinking' on this is that there's a v. simple pressure regulating device in the shower in the form of an elastomeric ball(?) that's squidged (engineering term) in to a restriction; this 'over-reacts' to the change in pressure. If the device is worn and has been the same way round for years it might be going in more than it should. Reducing the pressure allows it to move out and the flow increases.

[fred]

In article , jkn writes

Ever released a stuck gate by pushing before pulling, loosened a stuck fastener by tightening before loosening, percussive maintenance releasing a stuck starter motor bendix (or anything else). In short, fluctuations (either up or down can cause borderline things to temporarily fix themselves and attempting a full diagnosis before taking the cover off seems a bit of a waste of time.

Get the cover off and take a look.

[jkn]

Well, this is interesting/embarrassing...

After opening up the shower power unit and taking a look, I am reminded that in fact I've fixed this problem before and forgotten about it! ;-/

The pressure sensor microswitch, as well as yes, being bent back a bit, also has a tiny dollop of araldite on its button. I think I did this when taking a look at the very same problem, quite some years ago it must be now.

I think the reason I hadn't connected this with the recent symptoms is that I was never 100% that the problem had been fixed... can't remember if others were still reporting an occasional problem, or what. Either that or general old age starting to creep up...

Anyway, switch duly re-bent back in place, and initial reports are good. As fred has reminded me, the 'low/high pressure' weirdness can easily be ascribed to a combination of preessure on switch/switch body bending/pressure arm flexibility/ect/ect.

Thanks a lot Jon N

[fred]

In article , jkn writes

Glad you're sorted and thanks for feeding back :-)