Bathroom extractor fan questions

Wait for the humidity to drop.

Aye but that maybe be never if the wife has a shower every morning. Just a thought but if I taped off the part where moisture enters the sensor (a few small holes)would that eliminate the sensor and at least prove that is the issue?

Have you tried adjusting the sensitivity of the humidistat> There is usually an adjustment knob or screw somewhere.

Yes I have adjusted to the extremes either side for Timer & humidity.

With what you believe the unswitched and switched live swapped, did you try altering the sensitivity of both the humidistat and the timer?

If after checking with a meter the wiring is correct, I would start doubting the fan itself.

The sensor will be a fairly small component mounted on the PCB which is then mounted in a plastic fan case that is not airtight. Blocking off the holes is likely to make no difference.

In my experience the adjustments are not instantaneous.

Leave the light switch on Set the timer for minimum and humidistat to maximum and if the fan is on just leave it to see if if it goes off after a period of time. Leave it for the maximum timing period.

If the fan goes off after a period of time switch the light off then on again to see if the timer side just gives a short period of working.

With the timer still at minimum tackle the humidistat side. Adjust it downwards in say 5% steps and wait a while after each adjustment. Find the point at which the fan comes on and then raise the setting by say

The humidistat setting may need to be a lot higher than you think. I have a few cheap temperature/humidity meters (£4 Ebay) around the house they are currently showing around 68% humidity (perhaps with +/- 10% inaccuracy).

It sounds like he needs some kind of over ride system if he is really that worried about a low current fan running for a few minutes extra. Brian

That sorted it I was sdjusing bot to either max or min, by setting hum high and timer low it works perfectly...Thanks Just need to make small adjustments now.