Help with immersion heater and electricity

kunalsk8

Hi There,

I have an electric hot water immersion heater in my flat with a top heater and bottom heater and also a booster timer. Installed in my flat is a comfort plus meter through Scottish Power. I recieved my tarrif in for this year and says that I will be paying a fixed amount of £75 a month which seems to be very high considering me or my flat mate are not in during the day.

The water heater had both switches (top heater and bottom heater) on at all times with the unit beside it set at timer.

If i switch the top heater off and leave the bottom heater on will this save on the amount of electricity i use for Hot Water?!

Does anyone know of any cheaper providers that supply Comfort Plus?!

Many Thanks,

Kunal

Cardew

Welcome to the forum.

Firstly I doubt that you are paying a fixed sum of £75 a month if you have an account with Scottish power - I am assuming that you don't pay this £75 to your landlord.

£75 is the amount of the the Direct debit and this will be adjusted up or down depending on your consumption and by the way £75 is below average for an all electric property.

The top heater warms enough water for washing up, washing bowls etc, while the bottom heater provides enough for baths showers etc. Provided the timer is set to come on during the cheap rate periods of Comfort plus leaving them both on will not cost very much extra. In fact they are probably wired so they only come on during the cheap rate periods.

I doubt if there are any other suppliers who provide comfort plus; I assume you live in Scotland?

[Deleted User]

Hi,

if the tank is well insulated, you should only need the heater on for about an hour a day, so make sure the timer is set to come on about the end of the cheap rate, 11-7.30/12-8.30.

Premier_2

[Deleted User] wrote:

Hi,

if the tank is well insulated, you should only need the heater on for about an hour a day, so make sure the timer is set to come on about the end of the cheap rate, 11-7.30/12-8.30.

It obviously depends on many factors, but it'll take a lot longer than 1 hour to raise the temperature of say a 180l tank from say 20C to 60C with a domestic immersion heater

Energy required to raise 1Kg of water through 1 C is about 4200J (or 1.167W)

So to raise 180kg through 40C would be

1.167 x 180 x 40 = 8402.4 (or about 8.4kW)

That almost 3 times the rating of a typical electric immersion heater ... so it would take almost 3 hours (and that's assuming no heat loss at all). Some tanks are bigger than 180l, especially those designed for use with E7.

kunalsk8

Cardew wrote: »

Welcome to the forum.

Firstly I doubt that you are paying a fixed sum of £75 a month if you have an account with Scottish power - I am assuming that you don't pay this £75 to your landlord.

£75 is the amount of the the Direct debit and this will be adjusted up or down depending on your consumption and by the way £75 is below average for an all electric property.

The top heater warms enough water for washing up, washing bowls etc, while the bottom heater provides enough for baths showers etc. Provided the timer is set to come on during the cheap rate periods of Comfort plus leaving them both on will not cost very much extra. In fact they are probably wired so they only come on during the cheap rate periods.

I doubt if there are any other suppliers who provide comfort plus; I assume you live in Scotland?

Thank you for all your respones. I've only checked back today.

Yeah I do live in Scotland and as far as I know SP are the only comfort plus provider.

We don't really use the Hot Water that much - mainly only for dishes as we have an electric shower installed in the flat. The direct debit to scottish power as far as I know is set at £75. But, this will go down dependant on usage I guess. I have turned the top heater off and just left the bottom one on. Do you know if this will cause damage to the element on the bottom heater though?!

The timer doesn't give me an option to set particular times during the day when the heater is on or off. It just has a boost option (dial up to 2 hours) and a switch that says on/timed. Would it be an idea to get a serperate timer installed alongside this unit? Or does this already take in to account off peaks and peak times?!

Many Thanks for all your help.

Kunal