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Logomatic 2109 - constant call problem
I have been installing Buderus boilers for years and have never seen anything like this.
The 2109 I installed today had the dip switches set for a 10 minute purge on the circulator and boiler on stand down down for priority.
When the control was first powered I got nothing.
The 10 amp fuse was check and showed no resistance.
Replaced the fuse and the burner fired on a call for hot water.
after the tank call finished, the circulator ran well past 10 minutes and then the burner fired as the boiler lost temp.
It is acting as if the TT were jumped but they are not.
I pulled all the low voltage and still the burner fires and the circulator runs.
I am thinking that the mother board is toast but I am willing to listen to idea's.