Systemate SP118 hot water problem

[C Dayanandam]

Hi, I recently moved into this flat which has a maxol boiler and a systemate SP118 thermal storage unit. It looks like the whole setup was installed in 1997. The heating works really fine. But the hot water doesn't seem to be working. The boilor doesn't power on when the programmer turns on the hot water system. My landlord asked me to use an immersion heater fitted in the same thermal storage unit with a separate on off switch to get hot water. However it takes lots of time to heat the water and the immersion heater consumes 5kwh power in something like 30 mins. I would like to know how this thermal storage unit heats tap water. Should I always use the immersion heater for hot water or the boiler supposed to take care of hot water as well? Thanks for your help.

 

[picasso]

Hi yes the boiler should heat the thermal store to give you hot water as well as heating the rads, its most probably the 3 port valve thats gone wrong but could be programmer or stat,, I would contact your landlord again as using electricity is an expensive way to run your thermal store.

 

[C Dayanandam]

Thanks for your response. I did check the programmer thoroughly and it does its job as programmed. The "On" LED for hot water lights up during the programmed time, however, the boiler doesn't get fired. Even when I use the "+1 hour" option in the hot water section, the boiler (flame) is not turning on. However, the heating works just fine. I will let my landlord know about this and see if we can get this fixed.

Just one question: How much time will it take for the boiler to produce hot water? I tried letting it on for an hour. Should I leave it on for some more time to check my luck? Thanks again!

 

[Madrab]

Yep, get the landlord in again, electric hot water is uber expensive and there is a much cheaper alternative installed he just doesn't want to spend the money to get it fixed, it seems.

With a thermal store, the mass of water needs to be brought up to working temp and then the boiler maintains that heat store. Cold water flowing through that thermal mass is then heated to give you instant mains hot water. So it's not a case of how long it will take to give you hot water, like heating a cylinder, but how much water is in the store that then needs to be heated sufficiently first before that water can can then heat the mains cold to the correct temp.