Faulty light switch causes shower pump to start up

[sparkol]

Went to look at a job where the customer was complaining of his bathroom lights working intermittently and also that sometimes he was hearing ‘a loud noise like thunder’ when he turned his bathroom lights on.


Found that the connection in the light switch was ropey, and when the switch is partially open - i.e. when it is arcing across the contacts in the switch, the shower pump in the bathroom cupboard starts up for a couple of seconds!


My question for the kind users of this forum is… WTF?


The shower pump is on the same circuit as the bathroom lights but is obviously wired with permanent L+N (not into the switched L+N feeding the bathroom lights).


The shower pump is starting up for a couple of seconds even though the shower is not running. Otherwise the shower pump comes on with the shower when it should, and works fine.


There’s no RCD on the circuit as it’s an old Wylex. Megger values are fine. I checked for wires wrapped round pipes or anything like that and all looks fine.


Any ideas why this would happen? Should I just replace the light switch and not worry about it?


Thanks in anticipation.

 

[Plonker 3]

As usual, what test results did yo get when you tested the circuit.

Seems to a echo in here today.

 

[sparkol]

As usual, what test results did yo get when you tested the circuit.

Seems to a echo in here today.

252 mega-ohms on LN to E. Didn't do an R1 R2 (yet).

 

[GMES]

As usual, what test results did yo get when you tested the circuit.

Seems to be an echo in here today.

sorted that for you D

 

[Plonker 3]

Well go back and do it, what about L-N? Continuity of all conductors? These are basic tests that should take about a hour to carry out.

please don't tell me you have been to have a look and decided you need to ask on here as you don't know what you are doing?

 

[telectrix]

sorted that for you D

half sorted, half sorted. "yo".

 

[telectrix]

Well go back and do it, what about L-N? Continuity of all conductors? These are basic tests that should take about a hour to carry out.

please don't tell me you have been to have a look and decided you need to ask on here as you don't know what you are doing?

a tad harsh before beer time?

 

[Plonker 3]

Harsh?

The OP claims to be a spark yet doesn't even do the basic testing on arrival on site, just a quick LN-E insulation resistance test, bet they charged for that test too. Now that's harsh on the customer.

 

[GMES]

Tel, well spotted hawk eye and I am with dillb on this. I cannot imagine going to one of my regular customers on a fault and saying, Can you please wait while I go on a forum and ask the lads what they think it might be. They would never let me back in the place.
It seems everybody these day's wants spoon feeding! instead of testers I think some people on here would be better off with a BIB.
And for the record it is now officially beer o'clock....speaking of which!!!

 

[Maddison]

Well he's not going to be back anytime soon...

 

[GMES]

Well he's not going to be back anytime soon...

Why ever not ??????

 

[sparkol]

Well go back and do it, what about L-N? Continuity of all conductors? These are basic tests that should take about a hour to carry out.

please don't tell me you have been to have a look and decided you need to ask on here as you don't know what you are doing?

I used the time I had available to ascertain that the switch was faulty, megger the circuit LN to E and look at the wiring in the loft. I couldn’t replace the pull-switch as I didn’t have one in the van.


Rather than charge the customer for an hour’s worth of testing, leave him with a faulty switch anyway, and make myself late for my remaining jobs that day, the sensible course of action appeared to be to go back when I had more time, a replacement switch, and the thoughts of the helpful people of this forum.


If you don’t think that was the sensible course of action then it would be useful to know why.


It would be even more useful if someone could help with the queries in my original post.

 

[Maddison]

Why ever not ??????

Well for whatever reason he couldn't carry out further investigations. Dillb jumping down his throat does no favours for other people looking for advice on the forum ... It just makes people feel uncomfortable and go elsewhere,

 

[telectrix]

TBH, if i found what was obviously a faulty switch, i'd just replace.

 

[Plonker 3]

I used the time I had available to ascertain that the switch was faulty, megger the circuit LN to E and look at the wiring in the loft Why look at the wiring when testing it with the proper test equipment will tell you all you need to know about it?. I couldn’t replace the pull-switch as I didn’t have one in the van.


Rather than charge the customer for an hour’s worth of testing, leave him with a faulty switch anyway, and make myself late for my remaining jobs that day so why didnt you say you were busy and available another time when you wouldnt be rushed? , the sensible course of action appeared to be to go back when I had more time, a replacement switch, and the thoughts of the helpful people of this forum. Its only helpful when you can supply all the test results, not just a quick LN-E IR test.


If you don’t think that was the sensible course of action then it would be useful to know why.


It would be even more useful if someone could help with the queries in my original post. You will recieve help, but only once you have done all the testing as previoulsy stated.

Replied as relevant.

This forum isnt a one stop remedy shop, if you arent competant/confident in fault finding, its OK but at least admit it, none of us are perfect but really there are so many basic things to do before asking on here for some help.

 

[Plonker 3]

Well for whatever reason he couldn't carry out further investigations. Dillb jumping down his throat does no favours for other people looking for advice on the forum ... It just makes people feel uncomfortable and go elsewhere,

I haven't jumped down anyones throat, I asked for test results of the basic tests. Which weren't done.

Also why it takes 2 visits to diagnose a fault.

If people are paying for time the least they should be given is the above information, so they can at least make a decision on weather to repair it or not.

 

[GMES]

As above Sparkol, if your bored and just want a chat that's fine, if you don't know how to fault find with a test meter then just say so.
But to echo previous replies, you have got to at least do the basics before asking for other people to fix it for you.

 

[telectrix]

i'm just wondering what test might show why the pump is kicking in when it should not. seems as though the arcing of the faulty switch is the cause and a simple replacement would cure the fault. then again, i learnt my fault finding with a wind up megger and a test lamp.

 

[sparkol]

Dillb - I find the majority of faults tend to be resolvable within an hour, but a few can take much longer. When I have 2-3 weeks’ of work booked in ahead of me, and an employee who I have to pay whether we are working or not, then the practicalities of the job mean I can’t just leave a clear day, or even a clear morning, for what might turn out to be a 1-hour job. I find the best way is to tell the customer I’ll have time to come and have a ‘quick look’ and go from there. Are you a spark for a living, and if so how do you deal with this sort of problem? Don’t take that the wrong way - I’m genuinely interested to know how you and other people deal with fitting potentially open-ended fault-finding jobs into their schedule.



I appreciate what you say about ‘looking at the wiring’ vs testing, but looking takes 2 mins and felt it was worth it for the chance (however small) that I may have seen something helpful (even a plumbing issue given that we are talking about a shower pump here).



I fully appreciate that it is easier to comment when you have a full set of test results but one of the queries in my original post was whether it was even worth doing a full test given that, on the face of it, the problem was just a faulty switch. I also thought that, given the unusual and slightly amusing nature of the fault, people might find it interesting and perhaps even a little fun to venture ideas as to why a light switch would cause a shower pump to start up. It hasn’t turned out to be as fun as I expected.



I have to go out now, sorry, but will pick up later on.

 

[pjcomp]

I also thought that, given the unusual and slightly amusing nature of the fault, people might find it interesting and perhaps even a little fun to venture ideas as to why a light switch would cause a shower pump to start up.

Maybe it's only a light shower ... ?