Hot water only from 1 tap WHY?

[Needy]

Hi All

We got a baxi 105e

We only get hot water from the bathroom tap when turned on full

Downstairs runs cold also do the shower

To get hot water coming through the shower we have to turn the basin tap on full then turn the shower on at the same time.

Can anybody tell me the reason why and how to fix it

Thanks

 

[Boilerman2]

Sounds like the hot water Diaphragm is worn - needing a very large flow rate to fire the boiler, get the diaphragm replaced and all should be well
cost for a RGI to supply & fit the part should be around £60 - £100 depending on where you live

 

[Needy]

ok great thanks for that