I can`t get any hot water at all?? the central heating works fine. the water indicator on the boiler also isn`t lighting up? thanks Debbie

Debbie, October 2005

Is the micro switch the same thing as the diverter switch?

Shortyknickers, October 2012

Help I also have a turbo max Boiler, The hot water isern t working and central heating not working plus the water light also not working when i turn the hot water tap on, I have had the diverter value changed 12 mths ago could it be that again ? any idea please.

Phil Ridley, August 2010

I had same issue, no hot water, plus bolier not lighting when hot water switched on. It tried to light, but didn't and tap ran cold. Called engineer, who diagnosed Micro switch. Cost of part £18, plus £40 labour (would have been £60 but got discount as had service as well)
Works fine now!

Gareth, April 2010

really good advice, fixed my own using the info , watch when you buy the new diaphragm tho , the plastic bit on the needle is bigger, and i think it was stopping it going up enough to push the white rocker switch , also be careful when putting back the bottom of the housing as the diaphragm must not be out of line .
anyway alls well that ends well .
maybe one more question to the big brains , the water doesnt seem as hot now and thats even after replacing the sardine can bit with a bigger one 12 ltr per min , any advice welcome .

shane kennealy, November 2009

i m having same problem but i dont understand what is a micro switch or the thing thats cause the problem. Can any body explain me and from where i can get the faulty piece.
thanks

sonia, June 2009

why do we call plumbers enginneers?

Chris, February 2009

I meant to add that if I have the diaphragm section opened & push up on the "plunger" the diaphragm would normally move, this doesn't move the rocker arm either.

Any ideas appreciated.

Cheers

Rich

Rich, November 2007

Hi there

I have a similar problem - no hot water.

The white rocker arm doesn't come down. Have checked diaphragm, this appears okay but changed it whilst I had the chance. Still the white rocker arm doesn't budge. Any ideas?

Cheers, Rich

Rich, November 2007

on the right hand side of the pump as you look at it . get someone to run the hot water you will see the little white rocker arm come down to make the microswitch if it does not come down the diaphragm in the divertor needs changing as they stretch. if the white arm comes down and still no hot water replace the microswitch . please get a corgi engineer to do the the jobs as the diaphragm change can be a pain

gasman d33, October 2007

hi,i have the same problem no hot water,no water indicator lighting up,however will come on for short time then will not work at all,this device that operates the microswitch do you know the part name or part number and where exactly it is located to replace,thanks

jimbo, September 2007

http://www.mjtcontrols.co.uk supply all parts required, my microswitch for the same problem cost under £12.00 including p&p and was delivered in 2 days. Switch can also be bought from any Plumbase store.

Carol, November 2005

I to have had this problem. It was caused by a microswitch not being activated, and only effects the Hot water. THe system uses as small plastic rocker that is pushed down by a needle.

This small rocker is a cheap item that easily breaks/wears, last time I bought it cost cost only about £5. However, after a couple more years I now seam to be suffering the fault again and am trying to get a replacement...To call out Vaillant will cost £175 - flat rate!

The offending item is behind the pump on the far right hand side - should see a small micro switch. The "thing" thing that operates that switch is the culprit

Alan Knight, October 2005