I arrived for a new customer no heat call. I first spoke with the homeowner and and found that the heater runs all the time but won’t heat the house properly. I inspected the system and found the 15KW heat to be wired to run on only one heat strip. The power from the breaker box to the furnace in undersized from the construction of the home. I suspect that the system was unwired so the 15KW heat will not trip the single 60 amp breaker. I made this aware to the homeowner and told them that they are only heating about 33% of the systems capabilities. This one heat strip and blower motor are running at 23 amps. I wired all threes heat strips and for the total amp draw was 65 amp with all heating elements running. This is over the 60 amp recommendation. I wired two heat strip to run on one 60 amp breaker and the system is running at 45 amps. This is about 66% of the systems total heating capabilities. I recommended to have a electrician install a 30 amp breaker in the main breaker box an