Gas boiler to heating issue

[Mark DM]

Hi , speaking to a relative recently and they described a heating issue they have. Said I could post it up and see if anyone could come up with any ideas. They have a conventional wall mounted boiler on the ground floor and a hot water cylinder upstairs. When the hot water demand is required, 2 of the ground floor radiators go nearly cold. Once hot water is satisfied the rads then heat back up. I have little knowledge in this area so hopefully someone will come up with a diagnosis. Many thanks

 

[Schooldays]

Sounds like a balancing issue, unless a hot water priority system.

 

[Mark DM]

I did wonder about balancing but wasn't sure if that could affect the system with hot water being effectively on a separate circuit

 

[Schooldays]

It’s conventional system, which uses the same circulated water to heat the cylinder, so starving the rads when hot water is calling.

 

[Mark DM]

It’s conventional system, which uses the same circulated water to heat the cylinder, so starving the rads when hot water is calling.

Thanks, while there's hot water demand is that a good time to try and balance out the problem to some degree

 

[Schooldays]

Thanks, while there's hot water demand is that a good time to try and balance out the problem to some degree

I would yes, that way it can be distributed evenly regardless of which circuit it’s heating.