Strange DHW cycle behaviour

[Timbones (Tim)]

Related topics:

Kamstrup Multical 403 Stops Working During Hot Water Cycle (Interference?)

Here are a couple of other threads that discuss similar issues: Kamstrup Multical 403 Erratic flow readings - Hardware / Heatpump - OpenEnergyMonitor Community New emonHP install with strange readings - Hardware / Heatpump - OpenEnergyMonitor Community In my case it eventually resolved itself, especially after space heating started to run more often as we went into Autumn so it was probably dissolved air that was being released at higher temperatures when doing DHW runs. Hasn’t been a problem…

Advice from Marco:

Kamstrup Multical 403 Stops Working During Hot Water Cycle (Interference?)

Dissolved air in your system. Raise the fill pressure; get it good and hot; bleed the radiators; switch back and forth from DHW to purge the water with disoolved air from the DHW loop; bleed the radiators etc. Once there isn’t air in the flow sensor it will work correctly.