Pros and cons of water heater on timer
Jul 3rd 2014, 12:56 pm
#1
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Pros and cons of water heater on timer
I would really appreciate your thoughts on the pros and cons of having the electric water heater on permanently or on a timer and if on a timer what is the sensible length of time to put it on.
Graham set it up on a timer years ago but last week something went wrong with the timer so now it is plugged in permanently. I do not have any idea at all about what he had things set at but I know that the water was always burning hot. However now that there is only one person using the water I wondered about which system is the best so thought that I would ask you all.
Rosemary
Graham set it up on a timer years ago but last week something went wrong with the timer so now it is plugged in permanently. I do not have any idea at all about what he had things set at but I know that the water was always burning hot. However now that there is only one person using the water I wondered about which system is the best so thought that I would ask you all.
Rosemary
Jul 3rd 2014, 3:03 pm
#2
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Re: Pros and cons of water heater on timer
It's a very difficult one to answer Rosemary - there probably isn't one straightforward answer.
It depends upon a few variables such as how well is your tank insulated and what is your pattern of hot water usage.
One opinion says it should be on all the time so you are not heating a full tank up from cold, another opinion says that it's pointless keeping a tank of water at a high temperature when you don't need to.
I suspect the answer is that either is right or wrong depending upon the circumstances.
The other problem is that it's not easy to test which is the most efficient regime. I suppose you could try different regimes over a period and note the electric usage to try to work it out but there is a lot of 'noise' in the system - other electric usage and so on - not easy. And very boring.
If it's any help, we put ours on first thing in the morning and off again after the morning shower/bath/washing up rituals are finished. This leaves enough hot water for just about anything we need during the rest of the day.
I would guess if, like us, you have a peak usage time it's worth just heating up the tank for that and then switching it off but if you use water regularly throughout the day it would seem to make some sense to leave it on all the time.
Bit of a rambling answer with no real conclusion I'm afraid. I would like to see any other opinions on this...
It depends upon a few variables such as how well is your tank insulated and what is your pattern of hot water usage.
One opinion says it should be on all the time so you are not heating a full tank up from cold, another opinion says that it's pointless keeping a tank of water at a high temperature when you don't need to.
I suspect the answer is that either is right or wrong depending upon the circumstances.
The other problem is that it's not easy to test which is the most efficient regime. I suppose you could try different regimes over a period and note the electric usage to try to work it out but there is a lot of 'noise' in the system - other electric usage and so on - not easy. And very boring.
If it's any help, we put ours on first thing in the morning and off again after the morning shower/bath/washing up rituals are finished. This leaves enough hot water for just about anything we need during the rest of the day.
I would guess if, like us, you have a peak usage time it's worth just heating up the tank for that and then switching it off but if you use water regularly throughout the day it would seem to make some sense to leave it on all the time.
Bit of a rambling answer with no real conclusion I'm afraid. I would like to see any other opinions on this...
Jul 3rd 2014, 3:32 pm
#3
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Re: Pros and cons of water heater on timer
Thanks, I have been thinking the same sort of things. One minute I decide to leave it on all of the time then I decide that I should put it on a timer so that is why I thought that I would see what others say about it. The tank itself is excellent for keeping the water hot and is up in the hottest room (the washroom on the roof) so I have no worries there until the winter and to be honest have never noticed a difference.
Rosemary
Rosemary
Jul 3rd 2014, 3:37 pm
#4
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Posts: 192
Re: Pros and cons of water heater on timer
I suppose your heater is not the most modern type?? These days there is usually an "economy" setting which tends to be set some way short of "full". If your water feels too hot, try and reduce the temperature by lowering the setting to around 75% of maximum. Keep adjusting through use until you are satisfied with the level of heat.
On the basis of the economy setting I would suggest that it is better to keep the thing going 24/7, unless of course you are away from home for a while.
I expect that some better "expert" on here will give a more reasoned solution.
On the basis of the economy setting I would suggest that it is better to keep the thing going 24/7, unless of course you are away from home for a while.
I expect that some better "expert" on here will give a more reasoned solution.
Jul 3rd 2014, 4:50 pm
#5
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Re: Pros and cons of water heater on timer
It is always cheaper to heat it on a timer for a limited period.
If you had a perfectly insulated tank, it would make no difference, but they are all relatively poorly insulated.
The real cost of keeping it on 24/7 is the loss of heat. The rate of heat loss is dependant on the temperature difference between the hot water and the outside temperature. The higher the difference, the greater the heat loss - that is simple physics, not an opinion.
Jimenato says it is not easy to test - it is if you have a "power meter" which plugs in between the heater and the mains and actually measures the actual power used. I have one and have used it and it shows a very significant difference between the two options in favour of the time switch.
If you have a night meter system the savings are huge. Another important point is the reduce the thermostat to the minimum temperature that provides you with adequate hot water based on your usage.
If you use a lot in the early morning and another lot later in the evening then just set the timer accordingly to give two heating periods.
If you had a perfectly insulated tank, it would make no difference, but they are all relatively poorly insulated.
The real cost of keeping it on 24/7 is the loss of heat. The rate of heat loss is dependant on the temperature difference between the hot water and the outside temperature. The higher the difference, the greater the heat loss - that is simple physics, not an opinion.
Jimenato says it is not easy to test - it is if you have a "power meter" which plugs in between the heater and the mains and actually measures the actual power used. I have one and have used it and it shows a very significant difference between the two options in favour of the time switch.
If you have a night meter system the savings are huge. Another important point is the reduce the thermostat to the minimum temperature that provides you with adequate hot water based on your usage.
If you use a lot in the early morning and another lot later in the evening then just set the timer accordingly to give two heating periods.
Jul 3rd 2014, 6:18 pm
#6
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Re: Pros and cons of water heater on timer
It is always cheaper to heat it on a timer for a limited period.
If you had a perfectly insulated tank, it would make no difference, but they are all relatively poorly insulated.
The real cost of keeping it on 24/7 is the loss of heat. The rate of heat loss is dependant on the temperature difference between the hot water and the outside temperature. The higher the difference, the greater the heat loss - that is simple physics, not an opinion.
Jimenato says it is not easy to test - it is if you have a "power meter" which plugs in between the heater and the mains and actually measures the actual power used. I have one and have used it and it shows a very significant difference between the two options in favour of the time switch. If you have a night meter system the savings are huge. Another important point is the reduce the thermostat to the minimum temperature that provides you with adequate hot water based on your usage.
If you use a lot in the early morning and another lot later in the evening then just set the timer accordingly to give two heating periods.
If you had a perfectly insulated tank, it would make no difference, but they are all relatively poorly insulated.
The real cost of keeping it on 24/7 is the loss of heat. The rate of heat loss is dependant on the temperature difference between the hot water and the outside temperature. The higher the difference, the greater the heat loss - that is simple physics, not an opinion.
Jimenato says it is not easy to test - it is if you have a "power meter" which plugs in between the heater and the mains and actually measures the actual power used. I have one and have used it and it shows a very significant difference between the two options in favour of the time switch. If you have a night meter system the savings are huge. Another important point is the reduce the thermostat to the minimum temperature that provides you with adequate hot water based on your usage.
If you use a lot in the early morning and another lot later in the evening then just set the timer accordingly to give two heating periods.
Rosemary
Jul 3rd 2014, 8:01 pm
#7
Joined: Jun 2011
Location: In the middle of 10million Olive Trees
Posts: 12,053
Re: Pros and cons of water heater on timer
As Fred says, timer is my preference when using electric heating.
many say more electricity is used in taking it up to temp rather than continually on, but I have found that our continually on uses more electricity than the time system we had in the UK.
After all, if you want it you can already use the override button, but most people require warm/hot water at specific times of the day every day, so why heat it when it isn't needed.
the secret is in the times and also to ensure the thermostat is not set too high
hth
many say more electricity is used in taking it up to temp rather than continually on, but I have found that our continually on uses more electricity than the time system we had in the UK.
After all, if you want it you can already use the override button, but most people require warm/hot water at specific times of the day every day, so why heat it when it isn't needed.
the secret is in the times and also to ensure the thermostat is not set too high
hth
