Used a diesel hot water heater for over 10 years, I removed from T5 in September when I down sized used to use all year but stop using last spring
I only used it to make life easier but to be honest I'm still not sure wether to put back in the spare van, I'm happy as it is now, I use an additive which to be fair works as well on regular cleans
Service cost whom ever asked earlier was about 185 plus vat every other year
They are hungry for power you need to put in at least 2 battery's if you can at least 3 110 AMP not good if your stationary most days
I moved around a lot and clean between 8-12 house a day so ever had problem with batteries