Maintaining Heat in Water!

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debstar

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Can anyone help again please!

Can you tell me which is more economical?

Leaving the Imersion heater on 24 hours a day or switching it off at 9pm then on again at 6am. Which is more economical? Maintaining the temperature or reheating it? ?:|

 

The Godfather

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Depends on a number of factors.

1 Why is it being left on 24/7 ?

2 Is it a modern day tank, fully insulated?

3 What is the demand for hot water like through the day?

4 What are the supply charges and is a overnight rate of reduced electricity available?

You could experiement and switch on only when required and observe the bill, accordingly.

Rates for overnight use can be very economical and this is the period when most users heat their tank (Combined with a day time boost option).

Don

 

debstar

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There is quite a large amount of hot water needed during the day as i run a baking business from home.

The tank is quite old but has a very good jacket(recently fitted) which is very effective at maintaining the water temp.

Because the tank is switched off at night and i cannot put it on a timer i have to wait in the mornings for the water to reheat after i switch it on.

I don't have lower night time electricity charges but i just wondered if keeping the tank on overnight would maintain the temp,and whether this would work out cheaper than having to reheat it every morning?

 
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There is quite a large amount of hot water needed during the day as i run a baking business from home.The tank is quite old but has a very good jacket(recently fitted) which is very effective at maintaining the water temp.

Because the tank is switched off at night and i cannot put it on a timer i have to wait in the mornings for the water to reheat after i switch it on.

I don't have lower night time electricity charges but i just wondered if keeping the tank on overnight would maintain the temp,and whether this would work out cheaper than having to reheat it every morning?
Given your circumstances; quite possibly better to leave it on.

It is also worth noting that there are instantaneous hot water units, which may be more beneficial to you, in the long run. Or even a real, gas powered combi????

 
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I don't have lower night time electricity charges but i just wondered if keeping the tank on overnight would maintain the temp,and whether this would work out cheaper than having to reheat it every morning?
Find a kid doing A level physics and get him to work out some thermal heat equations. Work out heat needed and then cost of electric (you will also need to measure temperature drop overnight). I would do this for you but quite frankly its been a long time since I did my A levels. This will then give you a difinitive answer to your qeustion, and will also give answers to the payback of instantaneous water heating systems as suggested above.

 
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Hello there..

a few questions spring to mind from your posts..? ?:|

There is quite a large amount of hot water needed during the day as i run a baking business from home.The tank is quite old but has a very good jacket(recently fitted) which is very effective at maintaining the water temp.
Is this the same tank & immersion mentioned on this thread?

http://www.talk.electricianforum.co.uk/showthread.php?t=779

Pre 1976, 30+ years old?

IMHO no matter what sort of jacket you put round it, it would never be as good as a modern cylinder with the totally encased type of foam insulation moulded & stuck around the outside of the cylinder.

If you are leaving the immersion on... how do you know the jacket is good at maintaining the temp?

As you also say you have to wait for it to heat up if you do switch it off?

Are you sure you are not loosing a lot of wasted heating energy?

Because the tank is switched off at night and i cannot put it on a timer i have to wait in the mornings for the water to reheat after i switch it on.

I don't have lower night time electricity charges but i just wondered if keeping the tank on overnight would maintain the temp' date='and whether this [u']would work out cheaper than having to reheat it every morning?
What is the reason you cannot put a timer switch on?

is the element greater then 3kW?

A basic 24hr or 7day timer can be purchased for around

 

extension15

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Ah...

I'm watching football:D and responding to 2 forums at the same time..

Tricky at the best of times..

:D

 

Admin1

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Ah...I'm watching football:D and responding to 1 forum at the same time..

Tricky at the best of times..

:D
This is the ONLY place to be. :D

 
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As well as all the above wonderful comments, You could fit a economy 7 type cylinder. This has 2 immersions, one at the bottom to heat the whole cylinder and a second at the top to give a quick heat up of 1/4 of the cylinder. You can connect these to a normal electric supply, but may need some additional wiring

 

Stoday

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Logic says you'll always save by switching off. Question is, does it? Is it worth it?

Well, I got an old fag packet out & worked out a possible annual saving.

Wait for it... 26 kWh a year. That should be around

 
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Erm.....

`Scuse me??

r.e Legionnaires. If the customer only turns on their DHW when they want a bath; then, for the rest of the time, their tank is at a temperature of Tamb. Are you suggesting they are at risk of Legionnaires disease??

 

Stoday

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I'm only basing my comment on the Water Regulations Guide, G18.2

"Hot water should be stored at a temperature of not less than 60

 

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