vaillant combi

[mial]

hello all newbie can anyone tell me what would be the cause of got central heating but hot water is tepid boiler is about 12 yrs old thanks mial

 

[Puddle]

what model vaillant is it

Could be as simple as flow rate to high with very cold water coming into property at the moment,if you turn tap down does it get hot ?
Does boiler light when tap turned in ?

 

[mial]

hi thank you for your help itis model vcw gb 221h dont know if this helps you if you turn the tap down to slow flow or water it gets warmer also if you have a shower water is tepid but if you turn on cold water tap in bath room water gets hot thanks mial

hi dont know if i sent you a reply correctly so sent you this again it is vcw gb 221h vaillant combi dont know if this helps but if you turn the hot tap flow down the water gets warmer also in the shower water is tepid but if you turn on the cold water tap in the bathroom and let it run while your in shower water gets hotter in the shower hope this helps thank you mial

 

[Puddle]

Well turn heating off,if boiler does not light,will probably be hot water diaghram,if lights could be divertor valve stuck,so trying to do hot water and heating at the same time or you could have a blockage and main burner is only staying on low flame