boiler fires for upstairs but not downstairs

[jonnyohare]

I have a warmflow U70 boiler and just recently it has stopped working for the downstairs heating but not the upstairs or the water heating. when i boost it downstairs nothing happens but if i boost it for the other two it fires up no problem. all the rads downstairs are full and have no need to bleed them. please help, my wife is freaking out

 

[darrenangel]

are the downstairs rads controlled by a separate zone valve?

 

[GQuigley67]

must have something to do with your controls would get a professional out

 

[SimonG]

If it's an s plan then it's either a dodgy room stat/programmable stat if its wire free could be the batteries in the sender, or its a dodgy two port valve/motorised head. Take head off and operate stat/timer see if it operates. In the meantime you could open the motorised valve manually.

 

[diamondgas]

Hey Jonny,
Couple of things you can check before calling someone out; I'm assuming here that your heating system is split into 3 separate 'zones', 2 are working and one is not! If this be the case, check that the control for downstairs is turned on, if it's a room thermostat make sure its set to a temperature above the actual temp of the room & if its a wireless control check/replace the batteries! Some let you know that the batteries are running low! If all that is done and you're still without heat call someone out.

 

[stani]

could be the pump, gravity is running the hot water and also gravity is sending heat to up rads, if no pump then water wont be sent round rest of systyem.

 

[GQuigley67]

its the downstairs that isnt working though stani, so I can't see it being the pump. Seems to be a problem with controls or zone valve.

 

[stani]

its the downstairs that isnt working though stani, so I can't see it being the pump. Seems to be a problem with controls or zone valve.

yea, just re-read the start of the thread, its the 'boost' that threw me, it should be a zone valve if it is 2 zones, we need more info.

 

[GQuigley67]

i know what you mean, i thought he ment upstairs at first aswell until i read the OP again, you need to read them a couple of times to take it in haha