JUST WANTED TO SHARE THAT WE FINALLY GOT THE FREEZE UP ISSUE WITH OUR PROHEAT SOLVED. WENT TO CENTRAL STATES THERMO KING IN KANSAS CITY,KS. THEY ARE A MASTER PROHEAT SERVICE CENTER. THE PROBLEM WAS OUR UNIT HAD A IMPROPER CHARGE OF FREON. THE MECHANIC TOLD ME. THAT THEY HAVE FOUND THIS TO BE THE PROBLEM WITH MANY UNITS THAT WERE INSTALLED DURING THE WINTER MONTHS. HE SAID THAT THE SYSTEM IS SENSITIVE AND HAS TO HAVE AND EXACT CHARGE OF FREON. TO LITTLE OR TOO MUCH AND THE UNIT WILL NOT FUNCTION PROPERLY. THE WAY HE EXPLAINED IT TO ME WAS. THE UNIT DOES NOT USE A EXPANSION VALVE TO THE EVAPORATOR. BUT RATHER A SPRAY NOZZLE. WHEN THE UNIT HAS A LOW CHARGE IT PUTS LIQUID INTO THE EVAPORATOR, RATHER THAN A GAS. AND CAUSES A FREEZE UP PROBLEM. I READ IN ANOTHER POST WHERE DAVE KC. HAD ALSO SAID THIS PROBLEM. I DID NOT BELIEVE IT WHEN I READ IT. BUT HE WAS RIGHT ON THE MONEY. MY UNIT ALSO HAD A LEAKING WATER PUMP. WHICH THEY HAD IN STOCK AND REPLACED. SO IF YOU ARE EXPERIENCING PROHEAT PROBLEMS AND ARE IN THE KC AREA. CHECK THEM OUT. THEY ARE VERY KNOWLEDGEABLE ON PROHEAT. AND HAVE PARTS IN STOCK TO BOOT. I DROVE UP TO THE PLACE. AND THEY GOT ME RIGHT IN AND OUT.