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My Vaillant ecoTEC plus 418 was installed in 2009 on a vented system with twin 2-port valves and conventional Danfoss controls. It has been very reliable but in an effort to reduce the running costs I have replaced the Danfoss controls with a VRC 470f, VR65 and outdoor temperature sensor.
It's getting a bit too warm for any serious testing, but the first thing I noticed was chronic microfiring, which is well documented here:
https://vaillantcyclingproblem.blogspot.com/p/problem.html
This is what a CH cycle looked like on my data logger. The target room temperature is 18C.
One suggested solution is to set d.17 to return regulation, and that has certainly improved things. This is HW from 5am to 5:15am then CH from 6am:
I'm hoping some of the experienced users on here can help me with these questions:
Is the short cycling caused by the heat load being less than the boiler's lowest output (5kW)? If so are there any settings that can correct for this?
What should the Minimum Flow Temperature be set to?
What should Pump Blocking be set to?
Thanks,
Mike
It's getting a bit too warm for any serious testing, but the first thing I noticed was chronic microfiring, which is well documented here:
https://vaillantcyclingproblem.blogspot.com/p/problem.html
This is what a CH cycle looked like on my data logger. The target room temperature is 18C.
One suggested solution is to set d.17 to return regulation, and that has certainly improved things. This is HW from 5am to 5:15am then CH from 6am:
I'm hoping some of the experienced users on here can help me with these questions:
Is the short cycling caused by the heat load being less than the boiler's lowest output (5kW)? If so are there any settings that can correct for this?
What should the Minimum Flow Temperature be set to?
What should Pump Blocking be set to?
Thanks,
Mike
