Contractor came to do a semi-annual check on the furnace. He broke the control *** on the water heater by turning it too far up and then left it that way without informing us of the problem. When we discovered the water was scalding we tried to adjust it but the control was turned past the limit stop and would not adjust. Then a different service technician from Poudre Valley Air arrived and was unable to fix the previous tech's work so he started pointing fingers at the Gas Company, who we called at Poudre Valley Air's insistence because they said the gas pressure was too low. The Gas man did not have any interaction with the water heater, the Poudre Valley tech turned the water heater up to place a higher demand on the gas supply in order to test the gas pressure. The gas company returned while the Poudre Valley Air tech was still there and tried to explain that the pressure was fine for the load we had on the supply. The Poudre valley Air man presented us a invoice for $100 for the trip that was made necessary due to them breaking the water heater control which they did not fix and then he left a temporary jumper on the furnace that caused the furnace to run continuously after he left. The gas man and I were left with a broken water heater and a furnace running continuously and a $100 invoice after breaking our water heater and furnace. It is bad enough to cause the problem but then they try to invoice for their shoddy work.