Timed humidstat fan running oddly (split off)

[mermerus]

I am having a similar problem with a extractor fan timer. if any one can shed some light on how to resolve it i would be great full.
I have installed 2 Humidity / switch / timer fans in a summer house where I plan to site a hot tub, the fans are fitted in parallel brown to live blue neutral and black switch - there is no light connected to the switch side.
when 1st installed both fans operated on the humidity sensor when power was reconnected after adjusting the sensor control the fans switched off.
when the switch was operated again both fans worked and after adjusting the timer to the shortest period of run time they switched off.

Now the problem I am having

I switched the main breaker off at the fuse board to remove the fan covers and fans from the wall to allow painting of the walls not disconnecting the wires to the fans, after the painting was finished and the fans refitted tot he wall and the main breaker switched back on when I turn the fan switch on both fans run, but only one will shut off the 2nd fan keeps running for over a hour to stop it the main breaker has to be switched off again and left for 15 minutes, ( if the main breaker is switched back on to soon the fan still runs)
After the 15 minutes when the main breaker is switched back on fan 1 runs for a short period the turns off fan 2 does not run
If I switch the fan switch on again both fans run and again only fan 1 goes off with the timer

I am assuming that there is a faulty timer on fan 2 and I need to replace the fan but reading this post I am wondering if fan 2 is in some way effected by fan 1 with a current being feed from fan 1 to fan 2 keeping the timer circuit closed .

any thoughts or suggestions on how to test / rectify this problem apricated

 

[muffking]

The fans will be running on the permanent live (brown). So if you measure the switched live (black) to neutral you can confirm that the switched supply and feed from one fan to the other is off, therefore proving that the fan which won't turn off is faulty (or at least the humidistat isn't woking properly).