Can someone explain this system

[efficient]

Hi, can someone explain this system please. No mid position or zone valves and system runs of a Randal 102 which has heating and hot water settings. How is the hot water controlled with no valves, or could this be a C plan with a zone valve hidden away.

 

[snowhead]

Hot Water temp is controlled by the boiler stat setting.

Very common system when C-H started to become popular in the 60's /70's

 

[Ermintrude]

Performs badly?

 

[SafeGasInstall]

where is the 22mm going up to ? is there just a auto air vent ?
likely c plan with pump under the floor or back boiler with pump an mv next to it

 

[efficient]

It's got no stat on the hot water cylinder, don't understand how it can have hot water only from the controller ??

 

[IDCHAPPY]

Came across something similar the other day, tenant was complaining about bubbling noises from her cylinder, turned the stat on her BBU from max to about 2 and things were better after that.
Still shocking crap though

 

[SafeGasInstall]

programer will give ch any how , and if hw need will open hw along with ch

 

[efficient]

The boilers an old glow worn heat save 80B, shared vent and feed

 

[SafeGasInstall]

It's got no stat on the hot water cylinder, don't understand how it can have hot water only from the controller ??

can not give hot water only

 

[efficient]

That's what I said to the owners, but they reckon when they turn the room stat down they get hot water only.... Must be a valve under the floor