DIY Doctor UK DIY Forums

Hi all,

Since a 12 years old Horstmann programmer failed, I have replaced it with a new Sangamo unit (CHPPR3). This seemed to operate the three channels correctly but I noticed it ran slow and lost a lot of time, hence was not fit for purpose. The supplier sent me another unit to try.

I fitted the second one yesterday, set time and date, and tested that each of the 3 channels operates on/off as it should. Time remained correct last night, and still correct this morning, but checking at lunchtime today the time showed as 11:02pm Sunday (and the Hot Water channel was off as would be expected at that time). Checking now, the time shows 03:44am today (the day and date is correct). The 2 heating channels and the hot water are all working exactly as they should according to the time displayed.

So, as with the first unit, everything seems to operate correctly except that it loses time.

It’s odd that 2 have the same issue, but I can’t see that this can be anything but a fault in the units.

Do you agree?

I have never set the date and time on my wall thermostat, it is auto corrected from the internet, with my older model it used a battery and never seemed to need setting except when battery changed, but back in the day of a programmer the time would go out with a power failure, but looked up your unit and it says Battery Type: Lithium Cell CR1225 so even with power cut should not lose time.

I would test the battery is showing 3 volt, but other than a discharged or missing battery if loosing time the unit must be faulty. I have not seen a programmer used for years, today normally part of the thermostat, so it does not switch off but switches down. But only 3 channel thermostat I have seen is the Drayton Wiser which is rather expensive.

I use to have my DHW on a time, as there was no tank thermostat, so 1/2 hour every other day, but it retains heat that well, it would hardly matter if heated at 8 am or 8 pm. I do have CH on a time, and since the TRV heads have time set and wall thermostat have time set if one went out it would really mess things up, As TRV opening will not warm room if boiler not running, But 4 are connected to internet so unlikely to go out, 5 are blue tooth, so if program not run they could go out, but so few things now need to be altered as clocks go forward or back as most seem internet connected.