Bathroom extractor fan with no timer. Can one be added???

Discussion in 'Electricians' Talk' started by CosRush, Mar 21, 2010.

  1. CosRush

    CosRush New Member

    I have triedsearching for a timer circuit tooverrun my bathroom fan.

    I did have one of the small 4" fans with a timer circuit to start with but it wasn't upto the job. Had to upgrade to a 6" and although it was quite expensive by comparison it did not have a timer.

    I would like the timer function and have searched but have not found much info on adding a timer.

    Having looked at 2x old fansI have here with the small timer circuit boards there is really not much too them at all.
    Unless I just haven't them I cant imagine these cant be purchased from somewhere and wired into the fan supply line.

    Can anybody offer any advice?

    Wouldit be possible to utilise a second cheaper 4" fan with a timer make a relay circuit that would power both fans from the one timer circuit output?
  2. seneca2

    seneca2 New Member

    If you know what you're doing, maybe you could take the timer psb from one of the old fans and graft it into the one you're using?
  3. I'm only a DiYer so I state this as an opinion and not a recommendation, but I know it can be done 'cos I've done it.

    You'll need to unpick the small PCB from the old fan enclosure and fit it into a new plastic enclosure remote from the new fan. Maplins sell just such 'project' boxes.

    I doubt however that it would meet any kind of regs as it is essentially a fudge. And it will obviously invalidate your new fan guarantee. The more regulatory-minded here might also warn that it will invalidate your home insurance, burn your house down, render you liable to prosecution, put a curse on your family and make all your hair fall out.

    Mount the new box on a piece of wood and make suitable strain relief arrangements so the cables aren't just held in place by the connectors in the new box.

    I would say you do need to be pretty competent to make a decent job of it. As I said I'm only a DiYer, but my job does involve quite complicated wiring and setting up of TV studio audio circuits so I'm not completely green. If you have any doubts (and your question implies that you have) it might be best left alone.

    But yes, it can be done.
  4. CosRush

    CosRush New Member

    Thank guys for the replies.

    Based on your replies I will give it some more thought.

    Many thanks.
  5. seneca2

    seneca2 New Member

    Safest way would be to buy a timer fan.
  6. state-it

    state-it New Member

    Best bet would to be get a humidistat and link that to the fan!


    Does exactly the job you want it to do.
  7. state-it

    state-it New Member

    Google it OP.

    You can get individual humidistats for less than £20 which you can add inline with your existing fan, but not from Screwfix (where you can buy a 6" fan with built in humidistat for £147)
  8. gripster

    gripster New Member

  9. Lectrician

    Lectrician Screwfix Select

    I have one in the van which has been floating around for ages.

    It came from a manrose inline fan kit. Didn't use the timer module.

    Oddly, I am fitting it to a different centrigual fan sometime this week! Otherwise, I would of let you offer me some cash for it!
  10. Removed 4

    Removed 4 New Member

    It's all very well removing the timer pcb from one 4" fan to another, I've done it a few times. But it's a different matter when comes to fitting it to a 6" fan with 2.5 x the wattage and 5 X the stalled LRC.

    Therefore, the O/P should consider using a conventional timer, or a TD switch for his 6" fan, and not indulge in bodged modifications from an inferior model.

  11. JP.

    JP. Screwfix Select

    What does ''stalled LRC'' mean Lucia?
  12. Lectrician

    Lectrician Screwfix Select

    Lucia - The one I was talking about is a standalone timer that comes with a standard sized PVC back box. Can be surface or flush mounted if you wish. Has an LED and timer adjustment on the front. L N SL in and L N out.

    It came with a manrose inline fan, and I guess is available as a seperate item...
  13. JP.

    JP. Screwfix Select

    I can understand Locked Rotor Current but cannot understand the words stalled LRC. Stalled implies that the motor is juiced and stuck and LRC is current from start to run (inrush maybe)..but how can you say stalled LRC?..don't understand that.

Share This Page

  1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.
    Dismiss Notice