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Baxi 40ga duo tec cycling a lot
So I improved the performance big time of the boiler by fixing the primary loop like ironman told me.
But when a zone, maybe a small zone at 1gom or may be a medium 2 zone of two 1gmp flow valves is on. The boiler fires, and instead of reaching and staying at my set water temp, it overshoots it up to 176(my mah CH tenp setting, options are 113 and 176)
Then pump overrun runs for 3 minutes, and after 3 min firing delay time I have set, it fires back uo and does it all over again.
It is still scavenging heat into the return from supply at close fitting T’s but not as bad when were connected twice in secondary loop. There is a grundfos pump in baci pulling on return, and I have 1 alpha 2 grundfos pump in basement before EP zone manifolds pulling on the supply.
I need to check the expansion vessel insise to see if idiot that installed it set the presseure correctly, but under full pressure boiler says 22.5-23psi, and is 15-17psi static when cold. Could the little expansion tank be effecting it? Or is the gas valve somehow not set uo right? I am running on propane, piped from outside wirh 3/4 black pipe and set on baci for propane.