S.154-1 on Viessmann Vitodens 100 B1HE-199

erickyung

About a month ago I had a contractor install a Viessmann Vitodens 100 B1HE-199 boiler with an indirect tank LAARS LS-SS-50-L. For the first 3 weeks of operation, I did not pay any attention to the whole system as it was working and producing heat and DHW until I got a notification on ViCare app that the boiler had a fault F.62-50. After consulting with my contractor, I unlocked it and let it operate again. I found quite a few warnings A.19-50 in Message History -> Warning prior to F.62-50 based on timestamp - not sure if they are related. It's been operating normally for the past few days now and there are no further A.19-50 warnings. However I've started noticing S.154-1 in Active Message -> Status when the boiler is OFF and there are many (recent 10) of them in Message History -> Status. While the boiler is ON, S.154-1 disappears from Active Message -> Status.

According to the manual S.154-1 is "Boiler internal flow-switch is in open position". It's reasonable to me that the flow-switch should be in OPEN position when the boiler is off - no flow; and it should be in CLOSED position when the boiler is on - flow detected. Is it normal to see an active S.154-1 when the boiler is off? Is the purpose of the status S.154-1 simply to let us know that the boiler is operating normal and safe?

Redbaran

S.154 is a Status Message; not a fault. It is telling you the position of the flow switch. If the boiler is in standby (no heat demand/no dhw demand) it will show S.154. That being said it can be useful for troubleshooting as well; if there is an active demand on the boiler, and it is not firing while showing S154 - the boiler is telling you there is no flow; possibly a circulator issue or an air bound condition as a few simple examples.

erickyung

Thank you @Redbaran for the confirmation!