Problem with Grassun Mechanical Timer

[Piperman]

Hi,
Would appreciate some help with problem with a Grassun Time on a Halstead Combi Boiler. Clock working OK and keeps time, however, as soon as I set the tabs it stops and will not keep time, so can't set CH for auto turn on. If I rotate the clock by hand, with tabs set, it fires the boiler, and turns it off if I turn it as far as the 'off' setting.

Thanks in anticipation

Piperman

 

[tamz]

Probably a weak motor. Pick up a new one. They are easy fitted

 

[Piperman]

Thanks for quick response, Tamz, - the clock is a new one, when you say 'weak motor' are you referring to the clock or some other part? Thanks, Piperman.

 

[tamz]

The motor on the clock. The motor is too weak to push past the tappets. These are basic simple cheap yet usually reliable timers.
You don't need one specifically for a Halstead. They are all pretty much the same. 2 -4 wee screws hold it in and the connections are spades. There are 4 wires. Live, neutral (to the motor) and 2 switch wires. There is a diagram on the back of the clock but they are all the same.
You could also fit an external timer or wireless programmable room stat which are better if you feel a bit adventurous.

 

[Piperman]

Thanks again, Tamz, for that explanation. What puzzles me is why the clock stops turning only as soon as I set some tabs. Push all the tabs in and the clock keeps time OK.

I think I will take heed of your suggestion and fit a programmable room stat - I saw your advice on another thread and will probably go for the Drayton Digistat RF701 / 3RF combination.

Thanks - Piperman

 

[tamz]

When you pull the pins out, as the clock turns and reaches a pin it has to push past it to operate the switch. The motor is weak so does not have the force to do this so the clock stops at this point.

 

[Piperman]

Thanks Tamz, yes, I understand what you mean there, but for example, say the current time is 13.00 and I set tabs for say for 15.00, as soon as I do this the clock stays at 13.00 and will not travel around to the setting of 15.00. Push the tabs back in and the clock starts again......? this is what is puzzling me.