central heating and hot water operate at same time

[franby]

i have a new vaillant boiler fitted and both hot water and central heating come on at same time,i cant have hot water without central heating why?its not a combi boiler

[kia cat]

dont you have a control panel for start/stop times, isn't there an option for hot water and one for heating? Otherwise turn the heating thermostat down

[tezestwing]

Hi i'm sure kia cat means the room stat hth tez

[franby]

yes we have a control panel,but the electrician said when the system calls for hot water the heating automatically comes on,he also said the boiler will overide the room thermastat,

[tezestwing]

fran the boiler responds to roomstat/cylinderstat/froststat and any other temperature control all within the allotted programme times not the other way round if you are able to give a bit more information IE have you got a hot cylinder because if you have then the 3 port diverter valve could be at fault or installed with faults to wiring ? hth Tez

[terence7556]

hi franby what your electrician states does not make sense.
the whole point of the boiler interlock is that it is the modern way of controlling how your boiler works i.e. its all under your choice.does it really make sense to have central heating on in the summer when all you require is hot water? someone is not being straight with you. i have a hot water cylinder for stored hot water with two 2 port valves(S plan, because of the house size) and they are controlled separately, as yours should be .2 port or 3 port , it does,nt matter as long as they work or are wired in correctly.
i think the problem lies in this area as tezestwing has already indicated, unless there are some other facts you have not made us aware of.
i am watching this with a lot of interest and hope it resolves quickly toyour satisfaction

[gucciman]

is this a new replacement boiler that has been fitted into an existing system or is it a completely new system as well?

what is the make and model of your programmer?

do you have a room thermostat?

if it is a new boiler but an old system did you have the same problem when your old boiler was in place or has this only started since the new boiler was installed?

[franby]

thanks so much for your response,the old boiler was a baxi solo,we had no problems before they fitted this new boiler.it was avery good system that had been problem free from new 16 years ago.it is a pressurised system but i dont know the name of the tank model,it has a pump on either side of the tank,which were replaced at the same time.
the new control panel is a danfuss or danfoss,one side for water the other for heating,we have had to disconnect the heating side,to prevent it coming on.

[franby]

just update,its the central heating pump in the cylinder cupboard that has been disconected,just leaving the hot water pump wired up.

[genius1933]

the boiler has one flow pipe & one return pipe- The flow pipe goes to a diverter valve normally-this can go to 'hot water' only; CH only,or a mid position ,which sends the flow both ways.. The valve can be moved manually,it can stick! Try moving it manually so that flow is to 'hot water' only. Good Luck