Extractor fan

kerdiff

Hi Can an extractor fan be wired so when i pull my cord to turn power on for the shower the fan automatically comes on as well? The fan is connected to the light switch at the moment but I only want the fan on when the shower is on.

Steve

In theory, yes. not a DIY job tho.

2011

This is possible but why are you pulling a cord in the first place?

kerdiff

2011 wrote: »

This is possible but why are you pulling a cord in the first place?

It turns on and off power to the shower unit.

2011

kerdiff wrote: »

It turns on and off power to the shower unit.

This is an isolation switch that is installed for maintenance purposes. Switching it on and off before and after use of the shower is not only pointless, it often leads to premature failure of the switch. I would suggest that you stop doing this.

A current sensing relay could be installed on the shower circuit, that way once the shower is used the relay will switch the fan on. Alternatively would could install a humidity sensor that would keep the fan running until the humidity has dropped sufficiently.

kerdiff

2011 wrote: »

This is an isolation switch that is installed for maintenance purposes. Switching it on and off before and after use of the shower is not only pointless, it often leads to premature failure of the switch. I would suggest that you stop doing this.

A current sensing relay could be installed on the shower circuit, that way once the shower is used the relay will switch the fan on. Alternatively would could install a humidity sensor that would keep the fan running until the humidity has dropped sufficiently.

I saw this on the dublin fire brigade Twitter page and they say you should always turn off the isolation switch.

Bonzo Delaney

kerdiff wrote: »

I saw this on the dublin fire brigade Twitter page and they say you should always turn off the isolation switch.

Strange thing is . ..It was probably caused by constantly turning on and of the isolation switch .

2011

kerdiff wrote: »

I saw this on the dublin fire brigade Twitter page and they say you should always turn off the isolation switch.

I disagree. I believe that the frequent operation of the switch will cause accelerated mechanical wear resulting in a higher resistance connection which can cause overheating which possibly leads to a fire.

If you are going to follow that logic you should turn off the isolation switch for everything else such as:
- Bathroom extractor fans
- Hob
- Oven
- Immersion
- Gas boiler
- Dishwasher
- Microwave
- Circulation pump
- Fridge

.....and what about the things that are not fitted with isolators and are left permanently powered such as some detectors, satellite boxes, WiFi routers, intruder alarms etc....

Bonzo Delaney

Quiet possibly poorly fitted isolation unit screws not tightened fully on contacts causing an arc every time isolation is switched on burning out the housing untill eventually.... bang .
Would of been safer just left on from day it was fitted

2011

Every switch arcs to some extent when operated (if it completes a circuit). This can often be seen at light switches. As light switches generally draw a small current it has very little impact.

I think switching them under load is the real killer.
Just leave them on all the time.

Grab All Association

The extractor fan should be left on even after you’ve showered. Residual water/moisture can cause mould to develop.

Bruthal

Bonzo Delaney wrote: »

Strange thing is . ..It was probably caused by constantly turning on and of the isolation switch .

It does look like the fire originated in the shower unit itself though

This is it

Grab All Association wrote: »

The extractor fan should be left on even after you’ve showered. Residual water/moisture can cause mould to develop.

Yep, they usually have a switched and permanent feed for this exact reason.

Idioteque

Wow I had no idea you were meant to leave the isolation cord alone. Since I was a kid, I was always told to turn it off, anyone I've been around having showers does the same thing - as you can hear the loud click of the cord being pulled before and after.

So accepted wisdom is to leave isolation cord alone?. What do people do about the bright neon blue light when the shower is in standby? (or whatever the equivalent for a shower is called ) Ours lights up the whole bathroom and throws light out into the hall. Putting tape over it wouldn't look the nicest.

Seems strange that there's no way to turn the unit off fully then without cutting the power to it e.g. a TV in standby vs fully off but still plugged in.

2011

Idioteque wrote: »

Wow I had no idea you were meant to leave the isolation cord alone.

That is an opinion that I share.

I have seen many isolation switches fail over the years, in my experience most of the failures occurred with isolators that were frequently operated. Each failed isolator is a potential fire hazard.

Risteard81

2011 wrote: »

Idioteque wrote: »

Wow I had no idea you were meant to leave the isolation cord alone.

That is an opinion that I share.

I have seen many isolation switches fail over the years, in my experience most of the failures occurred with isolators that were frequently operated. Each failed isolator is a potential fire hazard.

I always advise when replacing them that really they're for maintenance if someone was to work on the shower and that there's no need to be operating them as the functional switch is on the shower unit itself.

naughtysmurf

Idioteque wrote: »

What do people do about the bright neon blue light when the shower is in standby? (or whatever the equivalent for a shower is called ) Ours lights up the whole bathroom and throws light out into the hall. Putting tape over it wouldn't look the nicest.

You could close the door? or isolate the supply, pop off the cover & unclip the led or neon from its holder & let it hang down or away from the lens a bit, you could put a bit of tape on the inside of the cover to partially cover it to dim the light emmitted

Idioteque

naughtysmurf wrote: »

You could close the door? or isolate the supply, pop off the cover & unclip the led or neon from its holder & let it hang down or away from the lens a bit, you could put a bit of tape on the inside of the cover to partially cover it to dim the light emmitted

There's glass portion above the door.

Yeah few options there thanks - still though, seems strange that if the shower unit is intended to be the main on/off (and not the isolator) that you are forced to have to do something like that to have an LED power indicator not showing. Maybe it's so someone doesn't think by merely pressing the button to turn it off there's no power going into it.

punisher5112

Went through 3 in a very short period at my father's....

Sister's were constantly at it and burnt them all out....

naughtysmurf

Idioteque wrote: »

There's glass portion above the door.

Yeah few options there thanks - still though, seems strange that if the shower unit is intended to be the main on/off (and not the isolator) that you are forced to have to do something like that to have an LED power indicator not showing. Maybe it's so someone doesn't think by merely pressing the button to turn it off there's no power going into it.

If it was my own home & bothering me that much, I'd just remove the led from the circuit but I'd be the only one that knows, it may void the warranty probably & cause some initial confusion by someone other than myself doing future maintenance.....some of those main shower switches are a pain in the ass to replace due to their location & lack of slack on the wiring, we leave our two in the ON position at all times due to the reasons given by previous posters

Usurper.

I've seen reports of shower fires but surely that would be showers while on

The standard shower pull cord gives trouble when operated

2011

I find it strange that people only consider this an issue with some electrical items such ass showers. Why not consider the risk with all of the other electrical items in a home that are left permanently connected? Thy would include satellite receivers, boilers, microwaves, dishwashers, intruder alarms, washing machines etc.

punisher5112

2011 wrote: »

I find it strange that people only consider this an issue with some electrical items such ass showers. Why not consider the risk with all of the other electrical items in a home that are left permanently connected? Thy would include satellite receivers, boilers, microwaves, dishwashers, intruder alarms, washing machines etc.

Very true, everything has the potential and all heat up....