Busted timer? Honeywell ST6200A

[cymroaur]

ST6200A timer malfunction. When set to HW only, it seems to work fine. However when set to CH + HW is comes on for less than a second, then seems to trip (the display goes blank). Then it comes back on, only to trip again. It will do this a few times, and every time it will stay on a little longer until finally it's on long enough for the valve to switch and start the pump. And it sat there quite happy, with the Override and +1 hour buttons doing their jobs on both CH and HW.

That was around 5pm, and at 9pm the timer should have kicked in. But it only did the HW. Once the tank reached its temperature the pump and boiler switched off.

The unit is over 10 years old, so I think the relays might have died. But I don't understand how it worked using the override, but not the timer.

Any thoughts? I'm going to have another look later tomorrow.

Thanks in advance.

 

[Andy Nicolaides]

Does anyone have a solution to this at all? Mine keeps shutting off now too.

 

[cymroaur]

In the end I installed a new timer. It was quicker and cheaper for the customer. Looked at it on the bench later and the relay was fried.

 

[Andy Nicolaides]

Thanks very much for getting back to me on this.
My hot water comes on, but CH+HW keeps clicking off. Does that still sound like its busted?
Do you know if I'd be able to find a replacement at a local Homebase / B&Q etc at all?
Is there an easy way to spot a broken relay?

Thanks in advance for any help.

Andy