Hi, I have a new propane gas furnace installation (we converted from oil). Everything seemed fine, except that the ground fault tripped in a bathroom, they tried the air conditioning, but it will run for a few seconds and then stop and at this time the furnace will turn on. They could not explain why this is happening. Now we tried to use the central vacuum and the motor won't turn on, even though there is power to the unit. What did they do? Somehow I feel all these things are related, please give me an insight on how these things are related. The contractor will send a service person tomorrow but I need to know what is happening.