It’s the thermostat

In a Whatsapp with the plumber (idraulico) he suggested I disconnect a wire from the thermostat to see if that would stop the heating pump. It did. But now no control on the heating other than turning the pellet-died boiler off and on - which is a bit of a drama as it burns what’s in its fire basket and then huffs and puffs to cool everything down for what seems like a good half hour.

Nice to see some of our tulips are finally out.

Thank you for your best wishes. Hopefully I’ll be up for some of tomorrow