Baxi Boston 2 hot water query

[willhay99]

Old boiler but I have problems controlling the temperature in the hot water cylinder. With the immersion heater off the water is heated by the boiler. A room thermostat controls the radiators temperature but appears to also control the temperature of the hot water in the cylinder "to the same degree". i.e. when the radiators are warm the hot water from the taps is too warm. Everything seems to be on a single zone sharing the same heating water from the boiler. I presume if I added a thermostat to the boiler that would simply override the room thermostat and turn the heat to the radiators off. Can't believe it was designed this way so there must be something I'm missing. There is a "water spreader" on the boiler but I think this is just for the heat exchanger.

Would a viable way of reducing the temperature of the hot water in the cylinder be to add a thermostatic valve to reduce flow as used on radiators.


any suggestions appreciated - thanks

 

[lame plumber]

old system, time to upgrade fm scratch probably

 

[boza]

sounds like you got poor mans fully pumped system with no two port valve to control hot water temp

 

[CM25]

I think u maybe miss understanding your heating system. could u post a few picks of the airing cupboard/ hw cylinder pipework arrangement?

 

[willhay99]

I think u maybe miss understanding your heating system. could u post a few picks of the airing cupboard/ hw cylinder pipework arrangement?

Afraid the cylinder is very difficult to access and photo since it's boxed in and highly insulated though I think I've found an exact diagram - appears to be a gravity hot water system with pumped central heating. Not allowed to add the URL (heating and plumbing solutions) but the notes suggest a motorised valve and cylinder thermostat are required to control the hot water in the cylinder.

 

[CM25]

Hi, if this is your system it's is a very old design with very little control of the hw temp if there is no cyl stat/2 port( only real control via boiler stat) . I would suggest ur best option is a boiler/system upgrade, next best an airing cupboard upgrade and cap off the gravity circuit at the boiler. U could have fitted a 2port and cyl stat but u will most likely also need a new 2 channel prog and wiring upgrades. Personally I would bite the bullet and go for a new system.