Combi - stopping the hot water

[PeterC]

I don't use the hot water from my combi, mainly because it doesn't get to the tap in time for most things and also, even with DHW 'off', it starts the boiler which then runs on for 5 mins.

Now , I don't like leaving the water 'dead' for 6 - 7 months of the year (the boilers off for ~5 months) and it's also useful, in Winter, to have some water that'll come through at house temperaure rather than rising main temperature. There's a 2-wire connection from the pressure switch to control the 3-way valve. I've unplugged this in the middle (convenient plug & socket) and that's stopped the switching. Is this a reasonable method and will it be detrimental to the boiler?

The boiler is a Vaillant Ecomax 824 E.

[Ret.]

My Worcester Bosch condensing combi has a small 'reservoir' of hot water that it keeps hot so that you have rapid access to hot water before the boiler itself brings hot water on line. I can, however, switch this facility off if I so wish. I don't know about Vaillant boilers - but it sounds to me like a similar system to my WB - and the boiler running for a few minutes is to keep the 'reservoir' hot. Are you sure that you cannot just turn off that facility?

[PeterC]

That facility is turned off. The boiler does a 5-minute run-on after reaching set point on CH to keep the water circulating; it does the same if CH isn't called for but DHW is used. All I want to do is stop the switching when the hot taps are used.

[funkyoldcortina]

You sure the boiler is running? On ours it's only the pump. The gas turns off as soon as the call for heat is gone.

[PeterC]

Well, yes, it's the pump, but as I don't want anything to start...