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Standy by battery on Horstmann H37 XL Progammer?

I have a Horstmann ChannelPlus H37 Series 2 Three Channel Programmer.
Instructions state it has a non-rechargeable, non serviceable long life battery which will maintain the clock & programme settings with mains supply disconnected.
The display on my programmer is not lighting up. I have tried the reset procedure detailed in the manual to no effect.
Does the stand by battery have a life span? as during the Covid pandemic the mains supply to the programmer was turned off as it is in a holiday home abroad that I could not visit.
If the battery is now dead can I just buy the same replacement programmer and fit it to the existing backplate?

Andy Merc
October 2021
I too had this problem and bought a new unit believing that the unit was non serviceable. After replacing I opened up the old unit to find it had a lithium battery soldered to the circuit board. It would be quite easy to remove the battery and solder the pieces onto a new battery and then put it back into the circuit board. Total cost would have been less than £5 rather than the £105 I paid for a new unit. I cannot understand how the manufacturer gets away with deliberately trying to make these non serviceable when they could have put a battery holder embedded in the plastic casing. They are still selling them like this when manufacturers are supposed to be green and make their products repairable!

July 2022

July 2022
You should easily be able to fit a replacement on the existing back plate.

See the reviews here:

I had a similar issue with an ESI programmer. On the basis of having nothing to lose I took it apart and fitted a new lithium coin cell but I future proofed it by getting a suitable coin cell holder and using an ordinary coin cell without solder tags.

Simple enough but there again, I spent many years as an electronic test engineer.

October 2021


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