I'd a 7kw arotherm plus installed beginning of the year. It has the cooling chip which had been working for about 2 months in the summer.
However, for the last month or so, when cooling is run for a while (approx 0.5-1 hour), I lose all water pressure. See that anti freeze valves are releasing all the water.
When cooling turned off, water pressure has been fine and hot water cycle can run without issue.
Installer changed both valves but still the same. Vaillant tech/engineer said it's not designed to have the anti freeze for this usecase. They can only recommend I remove the valves and use Glycol for anti freeze instead. My installer has not other suggestions.
Has anyone had similar issue or any other suggestions? TIA
