Hot water tank firing but heating and water off

[Alessandro]

This is a similar problem that I have, the system is about 2 years old Unvented, Nest with Baxi, and a Y system.

I have Smart meters, and can see the use of gas, while the heating is off and no call for hot water.

I have found the boiler firing up late evening 11 pm and cannot find why, it works fine to supply demand when required,

My current solution is to switch boiler off, (if I find it rouge firing) on the front of the boiler, this then allows pump to continue working to clear not required heat from the boiler, turn back on next morning and boiler fires up at normal @9am.

Has anyone met this with a Nest system?

I am currently having the same problem - the boiler engineer saying that it is a problem with Nest miscommunicating with the water boiler valves which then sends the wrong input to the boiler. ie boilers fires up for 1 min as Nest thinks we need a top up but only lasts for 30sec. Boiler /water tank/valves all good heating valve is good only have issue with the hot water side. Did you manage to find a solution? Thinking of calling a Nest installer Thanks for your help!

 

[mikerotherby]

Hard copy I’m afraid but you probably replaced receiver when you installed Nest.
Included this in case the receiver was left in place !

Hard copy I’m afraid but you probably replaced receiver when you installed Nest.
Included this in case the receiver was left in place !

 

[mikerotherby]

Thanks all for the help, it is the bio function so sorted