DeDoc Registered User
#1

Hi,

I've an electric shower fitted in the bathroom - about 3 years old. Gets used once or twice a day on average. There is a pull cord isolation switch in the ceiling.

Today the shower won't work. The light on the ceiling switch comes on, but the light on the wall-unit doesn't.

I've opened up both the ceiling switch and the wall-unit to have a look. The ceiling unit appears perfectly normal - no loose connections or anything. The wall-unit appears generally ok, but there is a fair bit of graphite around - I assume that is normal from the brushes wearing?

Is there a fuse within the wall-unit that I should be checking or could be replacing? Or any suggestion as to what part might be malfunctioning and needs replacing?

I have an identical unit downstairs that doesn't get used much (till today ) - so I could temporarily swap out components to test them I suppose. I don't have a multi-meter at hand, but can get one if needed, to test current flow etc.

Any help appreciated.

The shower unit is a triton t90xr by the way

evosteo Registered User
#2

very common problem,

simply replace the pull cord switch

due to the high currents going through the switch it causes heat and the plastic around the rocker in the switch to become maluable and interfers with the switching of the device. so even though the pull cord indicator light is on the rocker inside isnt making complete contact

IF YOU DONT KNOW WHAT YOUR DOING GET SOMEBODY WHO DOES AS ITS VERY DANGEROUS.

Switch should cost you bout 30 quid

stephen

DeDoc Registered User
#3

Thanks for the prompt reply stephen

I presume I can the switch in any good electrical suppliers, or maybe even in homebase etc?

I'm confident enough I can handle the disconnection of one switch and replacement with another - switch off at the fusebox, take my time, double and triple check the wiring and off we go!

What you say actually makes complete sense, as I recall the switch being a little 'stiff' recently - which would be understandable if the plastic had melted somewhat.

Bruthal Registered User
#4

If the shower is actually being turned on and the ceiling neon is still on, then the ceiling switch is not the problem, at least not the internals of the switch anyway. This does not mean there is not a connection problem at the ceiling switch, but this would usually show itself as badly burnt connections if the shower was previously working for a length of time with that switch. If a bad switch internal rocker connection is able to keep the ceiling switch neon on, then it should have the shower one on also while the shower is not actualy trying to be switched on. All assuming the neon is on the switched side.

Loose connections on the outgoing side of the switch would leave the pull chord neon on, but bad contacts connection in the seitch itself, which is before the neon, and the neon would go off when the shower is started as the connection fails from the load.

An electrician and multimeter would easily find where or why the connection is failing before the shower unit neon.

Bruthal Registered User
#5

DeDoc said:
I'm confident enough I can handle the disconnection of one switch and replacement with another - switch off at the fusebox, take my time, double and triple check the wiring and off we go!

What you say actually makes complete sense, as I recall the switch being a little 'stiff' recently - which would be understandable if the plastic had melted somewhat.


While swapping the switch could fix it, i would not assume its the switch for certain, because if the switch was connected the right way round, (neon on pull chord goes off when switch is turned off), then the neon will definitely go off if the switch has an internal problem when the shower is tried to be used.

And also the shower neon should be on of the pullchord one is on if the connection problem is before the pullchord neon, again assuming the pullchord neon is on the swithed side.

The real tests are to get a multimeter and check for supply at shower unit connections, and if power is there, try switching shower on, and see if supply is still at shower unit connections. If it is, then the problem is further on, as in something in the shower. Very simple tests for a competent electrician.

You could chance buying a switch, but it is not certain without doubt its that.

If the pullchord neon is on, and the shower one is off, then the problem is between the 2 neons.

evosteo Registered User
#6

theres alot of different makes of pullcord switch, some cheap, some quality, but what i can say to you is iv seen where the pull cord neon is on but no light at the shower unit.

honestly i can`t say how but i only assumed that the neutral rocker was stuck and the live feed only made connection somehow showing the neon flickering. these neons use very little current i assume.

as ya said earlier could also be loose connections in the switch.

could be a mouse chewed through the cable

all speculation really

Bruthal Registered User
#7

evosteo said:

all speculation really


You could well be right, all im saying is i would test the switch and shower first before just buying a switch to find the problem is a connection in the shower unit itself.

If 2 neons are solidly connected in parallel its hard to see one lighting and the other not if both neon`s are ok. We dont know if its a shower where the shower unit neon is on once the pullchord is on, like on a t90. Or if the OP actually tried operating the shower or just left it because the neon on it was off. Speculation is often all that can be offered here without very precise info.

A switch change could fix it though as said, if the OP wants to try it without testing anything.

Bruthal Registered User
#8

Anyway, tests for the OP to do,, with pullchord on. (Or just buy a switch and hope its that)

If the pullchord neon is lighting, and then switching on the shower unit puts the pullchord neon off, then there is a problem before the pullchord neon, probably within the switch.

If the shower unit is turned on, and the pullchord neon stays on, then the problem is after the pullchord neon, either the pullchord load side connections are loose, or loose connections or fault within the shower unit itself. No speculation there.

Dufftronic Registered User
#9

Get that multi meter you mentioned. It will tell you if you are getting voltage on the load side of the isolation switch. If you are, its your shower at fault and not the isolation switch. If there is no voltage, your switch is the problem. It's also important that the pull cord switch is only being used when the shower is off. Don't use it to power off your shower in normal usage, thats what the button on the shower unit is for.

DeDoc Registered User
#10

The shower when working will show both lights (shower unit and pull cord unit) on once the pull cord is switched on. Currently, only the light on the ceiling unit comes on, not the light on the shower unit. The shower unit on/off switch doesn't do anything (at the moment!)

I enclose the diagram from the shower manual. I'll test this tomorrow when I get a multi-meter

Attachments
triton t90xr.png
Dufftronic Registered User
#11

the problem is probably just the switch. Put the meter across the load side (the shower side) and check that you are getting around 230V between live and neutral. You should never do an electrical job without a multimeter tbh, its just not worth the risk.

Bruthal Registered User
#12

DeDoc said:
The shower when working will show both lights (shower unit and pull cord unit) on once the pull cord is switched on. Currently, only the light on the ceiling unit comes on, not the light on the shower unit. The shower unit on/off switch doesn't do anything (at the moment!)

I enclose the diagram from the shower manual. I'll test this tomorrow when I get a multi-meter


Did you look up at the pull chord neon as you turn on the shower unit switch as you would to have a shower, and see does the neon on the pull chord stay on?

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Bruthal Registered User
#13

Dufftronic said:
the problem is probably just the switch. Put the meter across the load side (the shower side) and check that you are getting around 230V between live and neutral. You should never do an electrical job without a multimeter tbh, its just not worth the risk.


If there is in fact a bad connection at the switch, 230v can still show up on it with no load on the circuit. Turning on the shower and seeing does the neon stay on is a very quick and easy test for the user to do.

If the neon stays on with the shower fully turned on, then the problem is no further upstream than the load side of the pullchord, and is somewhere either at or after the pullchord load side. (Unless anyone can think of a way the pullchord neon can be on with the shower fully on, and the fault before the pullchord neon)?

Bruthal Registered User
#14

DeDoc said:
The shower when working will show both lights (shower unit and pull cord unit) on once the pull cord is switched on. Currently, only the light on the ceiling unit comes on, not the light on the shower unit. The shower unit on/off switch doesn't do anything (at the moment!)


Just try switching the shower unit on and see if the pullchord neon goes out, as this can indicate if the problem is before or after the pullchord neon. The first thing after the pullchord neon is the pullchord load terminals.


Here is a simplified electrical diagram of a shower and pullchord.



Now looking at that, it can be seen that if the pullchord neon is on and you try running the shower, if the fault is before the pullchord neon, then the pullchord neon should go off.

If the fault is in the pullchord load terminals or after, then the pullchord neon will remain on when you try running the shower, suggesting the pullchord is ok.

The shower unit on/off switch in reality only brings on the pump and solenoid and does nothing more, but the neons are in parallel as in the diagram. The elements are then brought on/off by the water pressure switch, so the heavy load is not directly switched by the shower unit on/off switch as in my simple diagram above, but the pullchord neon behaviour should still indicate the fault location is either before or after the pullchord neon.

It could easily be the switch, all im saying is its a simple test which can indicate if it is or not. I am not a big fan of pullchords for loads as big as showers anyway.

If it is the switch thats the problem, and no signs of burning are present, its probably a mechanical problem in it as the lower quality ones suffer from this in the string pull mechanism. You are probably best leaving the pullchord switches on all the time, only switching off for servicing the showers.

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DeDoc Registered User
#15

Update:

Just home. The on-off button on the shower unit causes the pull-chord neon to go off when pressed. Press it again and the pull-chord neon goes on again. The shower neon stays on all the time

If I read the above correctly, this suggests that the pull-cord unit is faulty - correct? Will test with multi-meter later tonight or in the morning. Need to eat!

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