Thermostat kaput

kizkiz

Hi
Woke up this morning to find the heating on as normal. halfway through getting ready for work the hot water lost pressure and temp
The boiler is still lit and seems to be workign fine, but the thermostat is blank
It's a Honeywell ST6200A and appears to have died completely
I've checked the wiring and the mains and everything appears normal, but it just sits there blanka nd not doing anything :mad:

Is there anything else i can check or should i just get a new one?
thanks
kiz

daveys_2

Is the termostat separate to the boiler? Mine is on the staircase, uses infra red to connect to the boiler, but is battery powered, so when the batteries die, everything stops.

My termostat takes a couple of AA batteries

kizkiz

It's hard wired and attached to the wall near the boiler.
I call it a thermostat, but all it really is is a timer and clock to turn the heating/water on and off
I have no thermostat as such. Not the type where you can set a temp and keep the house to it

espresso

kizkiz wrote: »

Hi
Woke up this morning to find the heating on as normal. halfway through getting ready for work the hot water lost pressure and temp
The boiler is still lit and seems to be workign fine, but the thermostat is blank
It's a Honeywell ST6200A and appears to have died completely
I've checked the wiring and the mains and everything appears normal, but it just sits there blanka nd not doing anything :mad:

Is there anything else i can check or should i just get a new one?
thanks
kiz

It is not a thermostat, it is a programmable timeswitch and it sounds like possibly the display has failed, if the heating is still working normally. It if doesn't respond to being reset, then you will need a replacement.

zax47

Have you tried the reset button? The LCD displays on these do sometimes fail. If you do need to replace it, bear in mind it's now obsolete/no longer made. You might find one on Ebay, or I believe the replacement from Honeywell is the ST9400A. (1 day, 2 channel)

karl-123

reset button or batteries
clean the contacts or replace it with a horstman tiara

£ 5 e-bay £ 30 screwfix

http://www.screwfix.com/p/horstmann-425-tiara-programmer/18470?cm_mmc=GoogleBase-_-Datafeed-_-Heating%20and%20Plumbing-_-Horstmann%20425%20Tiara%20Programmer

you sound like you have a " bit of a clue " on how to use a multimeter and a screwdriver, so i am sure you will be fine.............

Myser

Have a look at this post on the Screwfix forums:

http://community.screwfix.com/thread/89566

It could just be a poor connection with the backplate.

Have you tried changing the batteries?

zax47

No batteries in a ST6200A, it's hard wired and system powered!

daveys_2

karl-123 wrote: »

clean the contacts

I did a Goo gle after my last post, and this seems to be the best advise (before you get your wallet out)

Myser

zax47 wrote: »

No batteries in a ST6200A, it's hard wired and system powered!

The Honeywell manual mentions battery backup however, I think they may be hardwired and can't be changed:

http://www.honeywelluk.com/documents/Reference-Guide/pdf/1040.pdf

Probably not related to the programmer completely not functioning though and most likely just to keep the time during a power failure.

zax47

Myser wrote: »

The Honeywell manual mentions battery backup however, I think they may be hardwired and can't be changed:

http://www.honeywelluk.com/documents/Reference-Guide/pdf/1040.pdf

Probably not related to the programmer completely not functioning though and most likely just to keep the time during a power failure.

Single built in back-up cell to retain time & user program data in the event of power fail. There are no user changeable batteries in an ST6200A!