New house. Underfloor heating. First signs of winter 2020. Heat pump starts showing errors and stops working. Provider and repairman need 4 months to figure out that the heat pump must be replaced with a new one. In between I must check the heat pump every day just so that it can not-work properly (only lets the floor be heated with 'raw electricity' (? not an engineer) if the error sign is not blinking & the error sign started blinking at least once per day).
How can I calculate (at least approximately) how much more electricity did we have to use when the heat pump was not working?
i.e. What is the difference between electricity used for keeping a house warm between when a heat pump is working and when it is not (and the house is warmed by raw electricity alone)?
I obviously need this information so I can know how much of the electricity costs I can demand the heat pump provider to return to me because of their slow repair and unwillingness to replace the broken machine sooner. I have received quite a large electricity bill (750€) that cover the whole period (+ some more) but can not determine how big part of that is due to the broken heat pump... So far the provider has only offered me 1 free yearly service, but since the heat pump always warns that 'if not working you may get large electricity costs' and it did not work for several months I believe this gesture is too little too late.