Why might I want to programme hot water times with my combi boiler?

Worcester's range of wall-hung Greenstar gas combi boilers all feature a 'domestic hot water preheat' function.

When this pre-heat function is on, the length of time taken to receive hot water at a tap will be reduced as the boiler will have been kept hot in readiness for a demand.

If this function is off, the boiler will only ignite to warm the water once the tap is opened. This means delivery to the tap will take a little longer but energy will have been saved in not keeping the boiler preheated.

The pre-heat function can be switched on and off manually according to your requirements by pressing the 'ECO' button on the front of the boiler.

The 'ECO' button explained

ECO illuminated green = energy saving economy mode, preheat off, slight increase in the length of time for hot water to be delivered.

ECO not illuminated = comfort mode, preheat on, quicker response to a hot water demand.

Programming the times for your hot water

Rather than managing the pre-heat function manually, a twin-channel digital programmer may be chosen which will provide you with the ability to programme the pre-heat to times of peak demand (for example when your household are all getting ready to go out in the morning) and also times of lower demand when preheat is not necessary automatically.

Watch a Boiler control video to see how to use the programming feature on your boiler control.

Please note
i) Our entire wall-hung gas combi boiler range will always produce comfortable hot water at the turn of a tap, you would only be programming the preheat function.

ii) Worcester's simple mechanical controls can only operate central heating and do not have the ability to control hot water.

iii) It is impossible to estimate the difference between pre-heat on and pre-heat off as it depends upon the temperature of the cold mains, the size and length of the pipe work to the tap and when the boiler was last used.


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