Pneumatic time delay switch keeps getting stuck?

[mxo]

Hi all,

I have a pneumatic time delay switch in a communal corridor. It looks like this:

http://www.screwfix.com/p/columbus-pneumatic-time-delay-switch/68088

When pressed, the round switch in the middle is meant to eventually pop out, turning the lights off again. But it keeps getting stuck, leaving the lights on.

Any suggestions on how to prevent it getting stuck?

 

[EFLImpudence]

Probably just dirty.

WD40 ? or a new one.

 

[OwainDIYer]

you can usually replace with electronic switches eg
http://www.screwfix.com/p/2-wire-master-push-button-white/65811
note a capacitor will also be required if your lights are low-energy.

 

[ekmdgrf]

If it moves and it shouldn't, use duct tape. If it doesn't move and it should use WD-40.

 

[winston1]

WD40 is a water displacement device (the clue is WD) not a lubricant. Use a thin oil.

 

[EFLImpudence]

WD40 will get rid of the dirt, oil won't.

 

[conny]

WD40 is a lubricant as well as a moisture displacement. It leaves a very fine film but has the added advantage that it does not attract dust like other oils/lubricants do.

 

[jtonline]

It doesn't help when people poke the pneumatic ones with a screwdriver or similar pointy thing to prise the central button out to its off position. Doing that causes rough bits on the plastic which just exacerbates the stickiness problem & then the switch needs replacing.

Edit: If you lubricate them, be aware that it may make them switch off a bit earlier than pre-lubrication. There's a screw on the back of the switch that adjusts the time it takes for the button to pop out. (Obviously you'd need to switch off the power at the consumer unit and prove the circuit dead before you tinker with the timing screw)

 

[RF Lighting]

Get a new switch. I tried loads of times on different switches various methods to free up sticky switches, and nothing ever works properly.

A new one won't break the bank.