Drayton Tempus 7 - battery replacement

[TopPosition]

I just got one of these off eBay. It's out of guarantee (May 2007) and was sold because the boiler had been replaced and so it was surplus to requirements.
There is nothing showing on the display (I haven't yet installed it), is it possible to replace the battery or might it come back once connected to the mains?

 

[TopPosition]

Battery is soldered onto the PCB.
That answers the first question.

 

[D_Hailsham]

According to the Spec, the battery will hold the data for 18 months minimum. Now, I can't imagine that to mean that the battery will run out after 18 months, especially as it is soldered in. So my guess is that it is a rechargeable battery.

Try connecting it to the mains via a lead and a 3 pin plug and see what happens.

Do you have the instructions? If not, Here they are!

 

[TopPosition]

According to the Spec, the battery will hold the data for 18 months minimum. Now, I can't imagine that to mean that the battery will run out after 18 months, especially as it is soldered in. So my guess is that it is a rechargeable battery.

Try connecting it to the mains via a lead and a 3 pin plug and see what happens.

Do you have the instructions? If not, Here they are!

Thanks. I do have the instructions. Will let you know the outcome

 

[AlanE]

It will normally hold the data for a time but unless it is one run by batteries, such as the Honeywell programable stats, the backup battery does not have the power to run the display so this goes off but everything returns to normal when mains power is restored.

Spec says it retains the program data for 18 months, time for 7/8 hours and display for 1 hour so you will probably have to reset the time and the programme to suit yourself but otherwise no problem.