Immersion heater help!

pinkbubble

Hi everyone... I'm new here, I joined for a bit of advice...
I'm moving to a different council house early next month, the new house is lurvely, BUT has solid fuel heating - there is a stove-type of thing in the living room which heats the radiators and hot water. There is an Immersion heater upstairs for the hot water too, but everybody has ooh'd and ahh'd and said it's extremely expensive, and not to use it At All. There's no timer on it, just an on/off switch like a light switch.
So, from always having gch this is going to be a big change... I'm a bit worried and I'd like to ask for some advice on the best way to heat the house & water as cheaply as poss!
I have children age 1, 4 and 5, so I need water in the morning for 1 shower and washing up, and then water in the evening to bath 3 kids and wash up, though I can always boil the kettle to wash up and mop - but isn't that supposed to be expensive too?
In the winter I'd imagine the fire will be lit pretty much constantly so there will always be hot water - but what is the best way to get hot water in the summer, or when it's not on? Obv I don't want the fire on now at this time of year, but I need hot water... so should I leave the immersion heater on all the time, or twice a day before we need the water?
There is no timer - can one be fitted? Otherwise I'll just have to put it on before I go to bed and switch it off first thing, and try to keep it as insulated as poss to retain heat for the day, then switch it on again for an hour or so before tea.
What exactly is 'expensive' as in, is there anyway to work out how much is costs an hour to run it?
I'm not used to sorting all this stuff out on my own, lol, so any advice would be welcome... just wait in 6 months time I'll be on here asking how to light a coal fire, haha

mute_posting

pinkbubble wrote: »

What exactly is 'expensive' as in, is there anyway to work out how much is costs an hour to run it?
I'm not used to sorting all this stuff out on my own, lol, so any advice would be welcome... just wait in 6 months time I'll be on here asking how to light a coal fire, haha

can't comment on the costs of heating water using solid fuel (presumably you'll have to buy coal?)

However regarding the IH, most are 3kW.

Assuming you pay 10p per unit of electricity (1 unit is 1kW for 1 hour or a kWh) your IH will cost 30p per hour.

Even though there is no "timer" the property may have Economy 7 and the IH could be connected to a off-peak supply from the meter meaning that it is only on for 7 hours (off-peak units if they are available will be circa 5p, but will make the peak units more expensive - say 12p)

Where is the IH in the tank - top, middle or bottom?

HTH

MP

Cardew

Just to clarify the post above - as the thermostat has not been mentioned.

It will cost 30p an hour when it is heating, but just because the immersion heater is switched on it doesn't mean it is heating or costing you anything to run as the thermostat has switched off the heater.

For instance after you have had your morning showers, it might only take 30 mins to heat up the water and then the thermostat will switch off the Immersion heater.

So there is no way to work out the cost - it depends how much hot water you use.

Perhaps the best way to calculate your costs is to take the average consumption of energy to heat hot water in a UK house.

That is approx 3,000kWh say 60kWh a week.

So at the time when your solid fuel heater is not providing Hot water, the immersion heater will cost approx £6 a week for hot water.

beingjdc

We have one of those immersion heaters. It's expensive as if you want hot water in the morning, it essentially needs to be on overnight, but not madly expensive.

It would be nice if the plug was a timer plug not a light switch, wouldn't it? I've asked the letting agent who are considering what they can do as it would improve the property.

My advice - invent something battery-powered or even better wind-up that goes over the top of such a switch and acts as a timer. Do some market research, build a prototype, and go on Dragon's Den.

Money problems over.

mute_posting

Cheers Cardew - excellent clarification!

I was talking about if OP just turned the IH on for an hour in the morning and again in the evening, assuming that it wouldn't reach the stat temp in thet time - should have made that clear.

MP

mute_posting

beingjdc wrote: »

We have one of those immersion heaters. It's expensive as if you want hot water in the morning, it essentially needs to be on overnight, but not madly expensive.

It would be nice if the plug was a timer plug not a light switch, wouldn't it? I've asked the letting agent who are considering what they can do as it would improve the property.

My advice - invent something battery-powered or even better wind-up that goes over the top of such a switch and acts as a timer. Do some market research, build a prototype, and go on Dragon's Den.

Money problems over.

It should have something a little more substantional than a lightswitch to switch 3kW! Although it may look like a lightswitch, it should be rated to at AT LEAST 16 amps, probably 20.

Unless you are being sarcastic, why re-invent the wheel? There are plenty of IH timers already on the market.

MP

pinkbubble

okeydoke, thanks for that, so - have I got this right, if I leave it on all day, the thermostat will keep clicking on & off all day to keep the temp hot? So it won't be constantly 'on' ? Or I could really buy a timer and have someone install it? That would be great. But which would be cheaper? Does an electrition need to do it?
I'm not sure where the thing in the tank is MP, I'll have a proper look on tues I think and report back. I don't think it's economy 7, just a plain basic cronky old thing with an on/off switch.
It's quite an old one I think, I want to make sure it's safe too!
Sigh, I'm really going to miss my gch combi boiler!


ps, lol @ the gadget invention!

Cardew

if I leave it on all day, the thermostat will keep clicking on & off all day to keep the temp hot? So it won't be constantly 'on' ?

Yes that is correct.

Or I could really buy a timer and have someone install it? That would be great. But which would be cheaper? Does an electrition need to do it?

A timer will be cheaper, but not by a huge amount.

Cyclone_Cyd

Pink,
Here's what to do:

1. No matter what fuel you're using, insulate the tank. If it's a plain copper tank get down to Wickes and buy two lagging kits. If it's got foam on it get one lagging kit. Insulate, insulate, insulate. Tank lagging is very easy to fit - you can do it yourself.

2. Contact your electricity supply company and ask if you can be put onto an economy 7 tarrif - if you're not already.

3. Contact a local electrician or plumber. Ask him (or her!) to check whether your immersion heater is an 11 or 27 inch version. What you're looking for here is to make sure that you get a FULL tank of hot from each charge. So you'll need a 27 inch fitted if it's only an 11 inch now.

4. Set the immersion thermostat to 70C. This is very hot, but should not be hot enough to cause scalding. Reason: to get the most heat energy into the water when using the immersion on E7, thus getting best value.

5. Have your Leccy fit a timer to the immersion along with a half hour boost control. Set the timer to come on at 5am and stay on untill the end of your E7 period (usually between 7 and 8 am in quarter intervals - ask your supplier). This will provide you with a full tank of hot in the morning which will be refreshed if you use some before the end of the E7 period. Only use the boost if you really need it outside the E7 period.

6. Try to bathe or shower in the morning before the end of the E7 period.

7. Try to find free sources of wood for the stove. Also buy a half load of logs in early autumn. Burn mostly wood during the autumn and spring months when it's not so cold. Do not burn tanalised wood (eg decking off cuts)

8. In the winter get a supply of house coal. If you're in a smokeless zone try and find a product called Excel at your merchants (it burns like a nuclear furnace!! I use it in my chiminea).

9. If you're out most days at work / school, then use a couple of 2kW fan heaters in the mornings during the E7 period rather than faffing with the stove.

10. Get the stove going as soon as you get home from work. Keep it going as long as it's needed. Add fuel half an hour before bed when it's coldest (so you can check it). Boost with the fan heaters if required (don't burn too much fuel and end up sweating, you'll just be wasting it).

11. Now you've got E7 run your washers and driers overnight on timers.

Economy 7 electricity is quite cheap, so use as much of it as you can. Similarly, wood is cheaper than coal, but has lower heat output, so only use coal when it's coldest. You can buy a device that makes fuel "bricks" out of all those free newspapers and junk mail. The stove will take a while to get going from cold, hence not worth using just for an hour or two in the morning when you've got E7 available.

Have the loft insulation checked and get the council to top it up to at least 8 inches if it's less.

Cyclone_Cyd

A timer will be cheaper, but not by a huge amount.

WRONG! Using a timer properly will be loads cheaper than just leaving it on.

mute_posting

Cyclone_Cyd wrote: »

A timer will be cheaper, but not by a huge amount.

WRONG! Using a timer properly will be loads cheaper than just leaving it on.

Exactly how do you come to that conclusion?

an immersion heater doesn't draw current 24/7 hence WHY a timer will only make a small difference!