Humidity Extractor Fan

[peter1971]

Hi guys! I wonder if anyone can advise me...

I have recently had my extractor fan replaced to one with a timer/humidifier detector. It is connected up to the fused switch to which the shower itself is also connected.

So here it is... When the swich is turned off it does what it's supposed to i.e. it runs with the timer and humidifier and then cuts off, but with the fused switch on (i.e. shower always available) it runs 24/7. Ideally I would like the switch to be on for the shower permanently and extractor only to run when the humidity levels are up i.e. the extractor to run as if the fused switch was in the off position. Is this possible?

Cheers.

Pete.

 

[holmslaw]

..

 

[peter1971]

Thank you very much. I'll get it seen to immediately. I had a feeling that it wasn't right - so much for using friends to help you out!

Sounds like a dangerous bodge, because there is no satisfactory way of taking a feed for a fan from a shower supply.

Domestic bathroom fans are normally taken from the lighting circuit via an isolating switch.

I would have thought a humidity controlled fan would just need a permanent feed, and would then run as dictated by the humidistat.

I'd get a proper spark (not the one that did the original bodge) to have a look ASAP.

 

[sparkybird]

Well, it might warrent a bit more investigation - the 'fused switch' impies that it's not an electric shower maybe?? Poss a pumped shower which could be fed from a 3/5A fused switch?

It sounds like the way bthat it has been wired it s bit up the spout though...

SB

 

[holmslaw]

..

 

[peter1971]

Thanks guys, I'll get a spark to investigate and set it up on the lighting circuit instead as per your advice.

Ideally I want the extractor to run 'indepedently' of the light switch itself as it has a timer/humidity guage built in - is this possible do you know? Will he/she need a new pull chord/switch to do this?

Cheers,

Pete.

Well, it might warrent a bit more investigation - the 'fused switch' impies that it's not an electric shower maybe?? Poss a pumped shower which could be fed from a 3/5A fused switch?

That did occur to me, but it sounded such a lash up that he needs a spark ASAP.

 

[holmslaw]

..

 

[peter1971]

Thanks Holmslaw. It is a supply for an electrically heated shower, with an isolation switch. I'm going to get a spark to check it out and check the wiring etc. Having thought about it, I don't mind the fan coming on with the lights and then running to time/humidity when the lights are switched off. It's a lot clearer now... Thanks very much for your advice - really appreciated. Cheers!

Are we talking about a shower pump or an electrically heated shower?

My original comments assumed the latter.

If it is a shower pump, then that supply could possibly be used to provide a permanent supply to the fan. The fan would then run when the humidistat operates.

The fan does require an isolating switch fitted beside it, in a shower room this would normaly be a pull cord switch.

 

[rebuke]

My fan is configured such that it will come on with the lights, and stay on for 15 minutes after i turn them off, or if the humidity rises above a certain level (so if i have a shower in the morning but don't bother turning the light on as enough light is coming in the window the fan still kicks in)...

The only problem I had was the humidity sensor is rather too sensitive, and it was very difficult to set it right, it was either always off, or thought there was enough humidity when there wasn't...)

 

[ban-all-sheds]

I have recently had my extractor fan replaced to one with a timer/humidifier detector. It is connected up to the fused switch to which the shower itself is also connected.

OK - I know we now know it's not a fused switch, but did they change how the fan was supplied?

i.e. did they just disconnect the old fan and connect the new one to the existing cable? Was the old fan always powered from the shower circuit?

 

[peter1971]

No...it used to be on the lighting circuit...but with the new humidifier/fan I was initially thinking that ideally the new one could run purely when humidity reached a certain level i.e. it would work independently of the lights so suggested (foolishly) we could connect it to the shower switch feed. This of course would now run every time the shower was available, again not ideal.

It probably wasn't such a good idea to a mate involved! I think it's now best to link it up to the lighting as it should have been in the beginning, so it comes on with the light at all times and off after the delayed timer/when humidity levels are reasonable. The model I have has an external humidity button, so I should be able to adjust it during the year easily.

I've called a spark to look at it tomorrow. Thanks for all of your advice/interest. Cheers.

I have recently had my extractor fan replaced to one with a timer/humidifier detector. It is connected up to the fused switch to which the shower itself is also connected.

OK - I know we now know it's not a fused switch, but did they change how the fan was supplied?

i.e. did they just disconnect the old fan and connect the new one to the existing cable? Was the old fan always powered from the shower circuit?

 

[ban-all-sheds]

It probably wasn't such a good idea to a mate involved!

No, not when neither of you know what you're doing....

I think it's now best to link it up to the lighting as it should have been in the beginning, so it comes on with the light at all times and off after the delayed timer/when humidity levels are reasonable.

So is it supposed to come on automatically, triggered by the humidistat, or is is supposed to be turned on via a manual action, and then when switched off carry on running until the humidistat is satisfied?

Does it just have a single live feed, or does it need permanent and switched?

Would you like it triggered by the shower being used (and I do mean used, not just "available"), and if so do you have access to the water pipe supplying it?