We have 3 upper level bathrooms where the shower temp has drastically changed in "2" of them. Our master bedroom shower all of a sudden only puts out only COLD water & my son's shower is scalding HOT? This happened to coincide immediately after we had a new refrigerator delivered from H. Depot and the service/delivery person shut our main water supply off while setting up the refrigerator? Our water heater is only 1 year old...how do we fix this! Could it have anything to do with them shutting the main water supply off while getting our fridge set up?