Specified power 8 kW ordered but I received 5 kW, not the power of 8 kW. Works well, only you need to let the exhaust run down so that condensate can also escape. In my case, condensate water remained in the exhaust, I heard bubbling and all soot came out of the exhaust. I blew out the exhaust, water came out, and the combustion was good again. I still need to change the exhaust.