Heating on to get hot water

[scottpetrie]

Hi
My mother in law told me she has to have the heating on to get hot water in the house. She has a condensing boiler in the loft, along with a water tank and a header tank, and a cylinder in the airing cupboard. The heating control panel doesnt have a hot water option on it. There is also an immersion heater in the top of the cylinder. Something has changed recently as this never used to be the case, there always seemed to be hot water whenever. She also has a switch in the kitchen for sink/bath & immersion on or off. Has anybody got any ideas what could have changed? Also, there is no room thermostat in the house for the heating. What sort of system is this?

 

[terryplumb]

Did she previously use immersion to heat hot water cylinder ,and it's now failed so using the boiler ? If the programmer never had a hot water only facility then that wouldn't have changed.

 

[CBW]

Something has changed recently as this never used to be the case, there always seemed to be hot water whenever.

Can you elaborate on this?

 

[fixitflav]

Hi
My mother in law told me she has to have the heating on to get hot water in the house. She has a condensing boiler in the loft, along with a water tank and a header tank, and a cylinder in the airing cupboard. The heating control panel doesnt have a hot water option on it. There is also an immersion heater in the top of the cylinder. Something has changed recently as this never used to be the case, there always seemed to be hot water whenever. She also has a switch in the kitchen for sink/bath & immersion on or off. Has anybody got any ideas what could have changed? Also, there is no room thermostat in the house for the heating. What sort of system is this?

Is it W-plan, that's what it sounds like? If so, failed contact in the cylinder stat would cause those symptoms. Cylinder stat calls but nothing happens due to the failed contact. Turning on the heating at the timer and roomstat fires the boiler, the cylinder gets the flow, the rads don't get hot because the diverter valve is not powered (as the cylinder stat is calling). When the cylinder stat is satisfied the diverter valve is powered (if the other contacts are OK) and the rads heat up, at which point she should turn the roomstat down if she doesn't want heating.
I'd start by cleaning the cylinder stat contacts, and if you can't access them, replace the stat.
W-plan sketch attached, it's easier to see what I'm saying than the full wiring diagrams on the web.

 

[scottpetrie]

Did she previously use immersion to heat hot water cylinder ,and it's now failed so using the boiler ? If the programmer never had a hot water only facility then that wouldn't have changed.

She said she used to use the immersion but its been that long she cant remember what switches were on and which were off. Theres one in kitchen & one (i think) on the cylinder. She never used to have to switch anything off or on so am assuming it was maybe always on?

 

[scottpetrie]

Can you elaborate on this?

Can you elaborate on this?

She says she never used to have to switch on or off hot water so maybe immersion was on permanently