Hi. Ignore the cascade bit. At this point it’s just a question about EI’s, how it is calculated and how the value determines whether the heat pump runs. The sense from everyone I speak to is that it turns off at 0 and back on at -60. I’m looking to see whether people have evidence that actually happens.
And yes Vaillant are aware of this matter as is my installer. Neither have answers.
How is the" Compressorhyster.Heat." setting ? Default 7K, max, 15K, means that when the flow temperature is above 7K than desired flow temp, the compressor stops regardless of the integral.
It may help to prevent the to early switch off.
Today I installed a new motherboard, which came with firmware 351.09.05 - previously I was on 351.06.05, installed in 2020. Mine is a 12kW unit. Below you can see the cycling before I installed it, around 0900 this morning, and after (please ignore the data error, still working on getting air out of the system!).
Currently I have everything default, so “Compr Start Heat From” is set to -60. I’ve just changed it to -100 now, so will keep an eye on it. Interestingly, my system only cycles above 10 degrees.
That’s quite a marked difference. Looks good now.
Did you manage to get Vaillant to swap the board for free under warranty? Or did you have to do this yourself?
Hi @Zarch sorry for the delayed reply - I didn’t get Vaillant to swap the board, I bought it from Pirate Heating and installed it myself.