Hot water tank temp

yellow218

Hi all

trying to cut down on the gas bills. Have managed to tweak the amount of time we heat the water and haven't yet noticed any cold showers! But also wondering whether we are heating the water to a temp too high anyway.

Does anyone know what the recommended temp of the hot water tank should be?

Is it better to heat it to a lower temp, and therefore not have to add cold water to it to get it to the 'right' temp, and therefore potentially use more/ have to heat more? Or heat a smaller volume to a high temp and add cold to get to the correct temp?


or am i purely over thinking it?

reeac

yellow218 wrote: »

Hi all

trying to cut down on the gas bills. Have managed to tweak the amount of time we heat the water and haven't yet noticed any cold showers! But also wondering whether we are heating the water to a temp too high anyway.

Does anyone know what the recommended temp of the hot water tank should be?

Is it better to heat it to a lower temp, and therefore not have to add cold water to it to get it to the 'right' temp, and therefore potentially use more/ have to heat more? Or heat a smaller volume to a high temp and add cold to get to the correct temp?



or am i purely over thinking it?

In theory you can save some fuel by lowering the temperature in your hot tank as that will reduce the heat loss from the tank and associated oipework. In practice the saving will depend on the amount of insulation on the tank and pipes - the more insulation the smaller the gain to be made. Worth trying a reduction of 10C maybe. Depends on how many people have showers one after the other ... you could run out of HW.

CashStrapped

The minimum recommended is 60 degrees for storage tanks as this ensure any legionella bacteria is destroyed.

http://www.hse.gov.uk/healthservices/legionella.htm

I would think it probably OK to have it around 50 degrees (it mentions this on the above link as a good distribution temperature), as long as you periodically turn it up to ensure the tank is "sterilised"every so often.

My tank is set to heat to a temperature where I have to add as little cold as possible (around 50 - 60 I think). Although as winter sets in, this becomes harder as I have one control for central heating and hot water (very old boiler).

bsod

the costs depend a lot on your particular suppliers charges, but hot water heating and cooking costs are usually a small percentage (<£100) of a typical households energy bills, and any heat lost from the tank heats the house up. so it's not wasted in winter.

it needs to be 60C occasionally to kill bacteria, under 55 aids bacteria growth

It's cheaper to heat it in one go, around an hour a day with a medium to high boiler thermostat setting

yellow218

Thanks all.

I've had a look at the hse link. Think ill put it at 60 and see what that does. Its at 70 now, so hopefully the reduction in temp, plus reduction in time heating will save some pennies.

Appreciate its not going to be mega bucks, but its somewhere to save money whilst not really being impacted in any negative way.

As my grandad always said: look after the pennies and the pounds will look after themselves.

footyguy

Don't get too worked up with scare stories of legionella bacteria

The tank thermostat is probably roughly in the middle of the tank.
If you set that at 50 degrees, the top of the tank will be much hotter
... and the bottom of the tank will be much colder

With it at 70 degress, the top of the tank could be almost at, or even be at, boiling point. Listen out for the bubbles!

Swipe

I've had mine set at 55C unaltered for about 5 years and have yet to contract legionnaire's disease