Viessmann Vitodens 100-W Compact boiler and pump overrun

[Agile]

Its a pity this thread died a few months ago. Also odd Alex did not get involved over the 2% Sedbuk.

I found what I needed as instructions on the Cylinder Demand unit.

Perhaps someone could confirm my expectation that if the relay in this unit identifies a HW demand then joining the two pins on the X21 its connected to then cause the boiler to ignore the external weather sensor and then to run at maximum temp?

Obviously that is not going to be the best temp for maxum efficiency.

I have a suspicion that I am going to produce my own unit to C/O the external sensor to a preset which will give about 70 C to the HW. Any coments on this?

Tony

 

[DP]

Tony wrote

I have a suspicion that I am going to produce my own unit to C/O the external sensor to a preset which will give about 70 C to the HW. Any coments on this?

How can you have suspicion about what you are going to or not going to do somethiung? Surely one has suspicion about something SOMEBODY ELSE is going to do surely

Getting back on track to boiler in question, I SUSPECTED the 100-W elevated primary temperature to be about 70 when HW zone was active. Surely you will be modifying the dedicated controls to get the boiler to do something the makers did not intend therefore working contray to Gas Safety (Installation and Use) Regulations stipulate