Technicians are extremely experienced in trouble shooting and locating the problem. Once this is done, they know what part or parts are need to correct the problem. They will not cut corners or accept an incorrect or poor installation. They correct it before they leave. They corrected the propane pressure which had not been done since the house was built. They also waited until a new cable was brought to them when the old one was 8 inches too short during the installation of a new unit. I will definitely call them again.