electric shower pull chord switch

bakerbhoy

Cannot find the answer to this anywhere in the regs.
Have a rental property,clients teenagers use pull chord as on/off for shower ,result three replacements of chord unit in last 12 months.Does the chord have to be present where there is an on/off on the shower unit and full protection back at the consumer unit.

M cebee

yes

try to replace with a quality pull-cord and you'll have less maintenance


any appliance needs an isolating switch

Bruthal

bakerbhoy wrote: »

Cannot find the answer to this anywhere in the regs.
Have a rental property,clients teenagers use pull chord as on/off for shower ,result three replacements of chord unit in last 12 months.Does the chord have to be present where there is an on/off on the shower unit and full protection back at the consumer unit.

The chord is required when the switch is in the bathroom. You can use a cooker type 40 amp isolator outside the bathroom on the wall if prefered though.

Dotsie~tmp

The 40A pullchord you see in bathrooms is NOT a switch it is an isolator. Switches perform the same job as isolators with the added function of being able to break circuits while under load. Operating the 40A isolator as a switch for the shower will lead to arcing and heat destruction very rapidly even with high quality switches. Warn your tenents not to do this.

From a contractors point of view I no longer fit 40A isolators for showers of ~ 8kW. Im tired of them burning out and clients denying they used it as a switch under load. I now used a contactor to isolate the shower load. The contactor in turn is controlled by a 10A neon switch or pullcord which is essentially currentless. The bonus here being almost zero chance of isolator burnout as its carrying no load. Also the contactor can tolerate breaking high loads if clients continue to misbehave and use the isolator as a switch.

One downside. The contactor is 40 quid, an extra cable must be pulled (4 core NYMJ i use) and a little bit more board work. Lets say it adds 120 quid. Thats what a changeout with burned cables might cost. You might pay this multiple times in the life of the shower if its abused. Likely never with a contactor.

Bruthal

Pull chord mechanisms are just not a good idea on a 40 amp switching device, a light switch should be their limit. Im not sure if a contactor switching arrangement would qualify as an isolator.

I dont remember having to replace a burned out switch i did myself yet, maybe its luck probably, or a bad memory. Have replaced a few jammed pull chords i fitted though. The mechanism in them jams, and sometimes they probably jam with the contacts not fully pressed closed. Wall switches i believe are better.

M cebee

Yes id be skeptical about that contactor method

Dotsie~tmp

M cebee wrote: »

Yes id be skeptical about that contactor method

The contactor method was advocated by ECSSA in response to the ever increasing kilowattage of showers and people breaking circuits with isolators. I can probably dig out the publication if anyone wants it.

edit: found

M cebee

Yes but what that article describes is switching not isolation -still not convinced

Bruthal

Isolatoin is the local disconnection of an electrical apparatus or appliance. The contactor is not locally isolating it. If you had multiple contactors in an industrial board and someone is working on that board, you could not be guaranteed the contactor in question would not accidently be switched in. So a local isolating switch would be required somewhere close to the appliance.

I know its a domestic installation, but the same applies, with an isolating switch, you will be safe to work on the shower no matter what happens at the board. Not so with a contactor. Its surprising to see that advocated as an acceptable isolating method by them instead of sorting the isolator switch problem itself. Even a fault on the twin brown that switches the contactor could cause the contactor to switch in.

M cebee

What they describe is functional switching. Unlikely imo it will comply with wiring rules

Stoner

about 25 years ago my mothers house was rewired, the 45 amp cooker switch isolating the shower is still going strong.

I have single gang 45Amp MK units in my place and they are also fine, no issues 7 years on, the showers are another issue. The best option is if possible to have the isolation switch outside the bathroom but near enough to the shower IHMO.

Bruthal

Stoner wrote: »

about 25 years ago my mothers house was rewired, the 45 amp cooker switch isolating the shower is still going strong.

I have single gang 45Amp MK units in my place and they are also fine, no issues 7 years on, the showers are another issue. The best option is if possible to have the isolation switch outside the bathroom but near enough to the shower IHMO.

Yea im describing them as 40 amp cooker type wall isolators, they probably are in fact 45 amp ones.

Stoner

robbie7730 wrote: »

Yea im describing them as 40 amp cooker type wall isolators, they probably are in fact 45 amp ones.

i didn't mean it as a correction, just as proof that a solid switch is the best option IMO, some are 40 and some are 45. I think the key is that they don't move and work the cables loose over time like the pullcord.

Bruthal

Stoner wrote: »

i didn't mean it as a correction, just as proof that a solid switch is the best option IMO, some are 40 and some are 45. I think the key is that they don't move and work the cables loose over time like the pullcord.

Yes i didnt see it as correcting at all, i am always calling them cooker type switches 40 amp switches when in fact some are 45A, the wall switches are definitely better in my experience also. I was never convinced pullcords were a great idea for shower type ratings, even if not required to actually break the load in normal use, they still have to open and close contacts capable of carrying 40 amps or so. A good solid wall switch has to be better alright.

goosey11

Hi. How’s it going lads. I realize this thread is old but the topic seems to be connected to the issue I’m having. I have an electric shower with a cooker type switch on the wall outside. The switch was recently changed because the other one burned out. I replaced it myself. Is there any possibility that I wired it wrong. I was told that if I wired it wrong the light on the switch would be on continuously. The reason I’m asking is because the shower doesn’t heat the water at all. Is this due to bad wiring or is it another issue? Thanks in advance

Sleeper12

This almost certainly an issue with the shower itself rather than the wall switch.

What's the make and model of the shower?

goosey11

Sleeper12 wrote: »

This almost certainly an issue with the shower itself rather than the wall switch.

What's the make and model of the shower?

Hi sleeper12 thanks for reply. It’s a Mira sport. Only 2 years old hasn’t been used for a while now due to the problem of water not heating. I replaced the thermal cut out switch myself thinking this might have been the issue but no luck. Also the filter had no sediment in it either

Sleeper12

It's a mains fed shower. If the Tco is working then it can only be the pressure isn't good enough to activate the pressure switch. If the pressure switch isn't engaged then there is no power going to the elements.

You need 1 bar of pressure and a flow rate of 8 or 9 litres per minute for a mains fed shower to work.

goosey11

Sleeper12 wrote: »

It's a mains fed shower. If the Tco is working then it can only be the pressure isn't good enough to activate the pressure switch. If the pressure switch isn't engaged then there is no power going to the elements.

You need 1 bar of pressure and a flow rate of 8 or 9 litres per minute for a mains fed shower to work.

Thanks that would sound about right because the water flow from the shower head isn’t very strong at all. Is there any way around that . Installing a pump to increase water pressure to the shower unit? Maybe the tank in the attic is limey?

Sleeper12

goosey11 wrote:

Thanks that would sound about right because the water flow from the shower head isn’t very strong at all. Is there any way around that . Installing a pump to increase water pressure to the shower unit? Maybe the tank in the artic is limey?

Water isn't coming from the attic tank, at least it shouldn't be for a mains fed shower.

If it is coming from the tank you need to repipe it to the mains

If it is off the mains then ring Irish water. They will come out free of charge & test the water pressure coming in to the property. If pressure is ok at street level then you have a leak. If pressure is not good at street level then Irish water will improve it.

goosey11

Sleeper12 wrote: »

Water isn't coming from the attic tank, at least it shouldn't be for a mains fed shower.

If it is coming from the tank you need to repipe it to the mains

If it is off the mains then ring Irish water. They will come out free of charge & test the water pressure coming in to the property. If pressure is ok at street level then you have a leak. If pressure is not good at street level then Irish water will improve it.

OK cheers for the info. Much appreciated.