heating water

emweaver

Do you think its cheaper to leave the water heater on all the time or only turn it on a few times a day?

Some people have said it costs more to turn it on and off as its got to restart and leaving it on all the time means it only heats a bit of water at a time rather than a full tank.

What do u think?

david29dpo

latest i have heard is its cheaper to leave on constant.

btr30

It will use less energy (and therefore cheaper) to only heat water when required. The heat loss from the tank is proportional to the difference in temperature and the surrounding air, eg. heat loss from a cylinder at 60 deg C water in a room at 18 Deg C, will be more than water at 40-30 Deg as it cools down after use. Your heater, whether it be a gas boiler or electric immersion heater, will be on longer to make up for this increased heat loss.
A well insulated cylinder and pipework, with a sensible time program to meet your demmand periods is the most efficient means of heating your water.

Cardew

david29dpo wrote: »

latest i have heard is its cheaper to leave on constant.

Completely wrong I am afraid.

http://forums.moneysavingexpert.com/showthread.html?t=493277

Look up Energy Saving Trust for further confirmation.

david29dpo

most likely yes. a new eps told me!

missile

:rotfl: Have a cold shower :rotfl:

emweaver

david29dpo wrote: »

most likely yes. a new eps told me!

sorry which are you agreeing with?

dc

Depends on what your heating system is.

If using an immersion heater then you should only switch it on to heat sufficient water for your immediate needs, just like they are saying only put the water you need in a kettle.
Same principles apply as the water tank will loose heat unless the surounding tempreature is higher than that of the water in the tank no matter how good the lagging.

With central heatiing systems used to heat water then it is not that straight forward and depends on the controls you have and the volume of water in your system. When hot water is required, all the cold water in the system has to be heated by the boiler first, to transfer heat to your hot water via the coil in the tank. If you have zone valves and the boiler is close to the hot water cylinder and all pipes are well lagged, then especially in Winter there may be no difference in cost by leaving the hot water on all the time in a busy household.

However in Summer it is likely for most of us that gas is inefficient as a water heater and timed use of an immerion heater would in most cases be less costly.

anniecave

Ours is a hot water heater and tank and only has an on and off switch (no timer) We leave ours on overnight every other night and off the rest of the time and that seems to work fine for us.
If it had a timer switch fitted we'd probably amend it to 3 hours every day or something.