Programmer turning off and on every 20 secs or so

[davidriddoch]

Hi,

Every few 10s of seconds my programmer is turning the hot water demand off and on again. (CH is turned off, so I don't know whether it exhibits the same problem).

The relay clicks off and the led turns off at the same time. Then about 1 second later both turn on again. Everything then works for 20 to 40 seconds and repeat.

Duff programmer?

Thanks,
David

 

[cozzmic]

There should be a reset on it, either a small hole with a button under or press a pair of buttons together. Would help if we know what programmer it is.

 

[Aquaheat]

I'm going to stick my neck out and say it's a 699

 

[cozzmic]

Could be a older worcester programmer and scrolling through the programmes. Have you had a power interuption?

 

[Simony22]

Sounds like you've got a Honeywell st699, the slider control isn't making the contact. Get a new st799 and its a straight swop.

 

[davidriddoch]

> Would help if we know what programmer it is.

Sorry, not obvious until I found the front cover that fell behind the cylinder!

Drayton Tempus Seven. (No sliders!).

Thanks very much.

 

[cozzmic]

Hi Dave,

I take it is a brown/cream colour programmer as in the old tempus 7? I think if you push a pair of buttons together it could reset but I cannot remember which ones. Say like prog and time button or up and down buttons. I am sure one combination should reset it.
You would belive it I have one that came out of a job the other day. Press clock/day to reset.

 

[davidriddoch]

Grey with a cream front cover. Like this one:

.

Combinations of Clock +/- and Day didn't manage to reset it, but I have tried removing power (including the backup battery) and that didn't cure the problem.

 

[cozzmic]

Got me on that one as doesn't look familiar.