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Hydrostat 3250+ adapting to new boiler?
I moved my Hydrostat 3250+ from a Weil McLain WTGO-3 to a Buderus g115 ws3. The Buderus has half the BTU and half the mass of the old one.
The Hydrostat will run the burner to the set max temp of 180 degrees. After the burner turns off, the boiler continues to warm -- today it got to at least 221. The Hydrostat appears to be running the burner longer than is needed, and I am wondering if it is using the target temperature or 'curves' it determined for the old boiler. Question: Is this a thing? How quickly do old data points get wiped from the Hydrostat's memory so it can learn and adjust for a new boiler? Does it not learn if the only calls come from ZC/ZR and not TT (because in the summer the only call is from the indirect tank)?
The Hydrostat's thermal pre-purge function is turned on, so it should only fire the burner when the latent heat available is insufficient to meet the demand. On the WM, the Hydrostat would show "Pur" on its display; on Buderus it never does (even though it appears to be in that mode, as the circulator is running but the burner is off).
Hydrostat settings: factory reset yes, then low temp off (cold start), hi temp 180, efficiency 4, pre-purge on, circulator on TT and ZC/ZR, circulator hold off active. Hot water and heat work; the system has been checked by a Buderus installer/servicer and is running properly.