Timer in PCB?

[Ben WW]

Hey all,

Managed to figure out we have a central heating system from an old style boiler and an immersion heater is managing our hot water.

My only concern is the cost of the immersion (I know they are expensive) but woke up this morning to see between midnight and 8am the current electricity bill was £1.60 with only the immersion to blame apart from a few pence per hour from standing appliances. Estimation is its cost around £1.20 to heat out hot water.

I wanted to reduce the time it was heating as at the moment it appears (from the Horstmann boost panel) to show that it heats between 3am and 8am.

The only 'timer' I can see is the one in the PCB which is happily ticking away. Apparently this seems not to be normal and even more strange the timings however do not match, thoughts?

P.S - I know this isn't cost effective and due to replace the system with a WB 38CDI Greenstar at the end of March but I wanted to get the wife off my back in the short term and save some pennies To boot.

 

[stem]

The immersion heater will heat the contents of your hot water cylinder and then switch itself off once the contents are hot. So, reducing the time won't make any significant difference.

It would seem, as you are using it at night, that you will be on an 'off peak' tariff (eg Economy 7 or 10) Most off peak timer controls are designed to make maximum use of the 'off peak' tariff so as to fully heat the cylinder to minimise the use of electricity during the day (which can cost three times as much as off peak). For this reason their 'on' times cannot normally be adjusted. Which would be unnecessary because the immersion heater's thermostat turns off the heater once the cylinder is hot anyway.

Insulation is more important so that the cylinder stays hot and does not cool so that the immersion has to keep coming back on to top it up because of heat losses.

But having said all of that, I am wondering if you have a boiler, why are using using the immersion heater in the first place, and not heating your hot water from the boiler?

 

[Ben WW]

The immersion heater will heat the contents of your hot water cylinder and then switch itself off once the contents are hot. So, reducing the time won't make any significant difference.

It would seem, as you are using it at night, that you will be on an 'off peak' tariff (eg Economy 7 or 10) Most off peak timer controls are designed to make maximum use of the 'off peak' tariff so as to fully heat the cylinder to minimise the use of electricity during the day (which can cost three times as much as off peak). For this reason their 'on' times cannot normally be adjusted. Which would be unnecessary because the immersion heater's thermostat turns off the heater once the cylinder is hot anyway.

Insulation is more important so that the cylinder stays hot and does not cool so that the immersion has to keep coming back on to top it up because of heat losses.

But having said all of that, I am wondering if you have a boiler, why are using using the immersion heater in the first place, and not heating your hot water from the boiler?

Stem - I have exactly the same thoughts in regards to the boiler but I can't get to boiler to fire up on demand for the hot water. It is a very old boiler Potterton Flamingo 50 and I'm not sure if the feeds are right for it to heat the hot water.

In any case the boiler is so intermittent (possible thermocouple or gas valve problem) that I dare not mess with it through fear of ending up without hot water at all - heating I can live without until the boiler is replaced in about 6 weeks time.

Fully understand regards the heating of the cylinder so guess I'll just live with the times as they are for now until replacement.

I was surprised to see the timing mechanism on the board though as was the BG electrician that came out recently.

I'm no longer on a two rate meter as was recently replaced but understand about the economy 7/10