02-04-2022, 06:37 PM
Okay, here's the deal.
The 4500 watt 240 vac element can run when there is a 50 amp two leg connection to the coach. The 1650 watt element runs on one of the two legs of this connection. Amp draw is near 37 amps.
When connected to 20 amp or 30 amp single leg connection, that leg is connected to both sides of the 240 element creating no potential difference across the element, so no current draw by that element. The 120 volt element is connected to the single leg and common or ground which has a potential difference and a current of about 13 or 14 amps will flow.
So if nothing else that has much of a current draw is ON, 20 amps will work. But, the burner and fans on the heating coils draw from the house batteries. The inverter charger has about 5 amps to use to keep the batteries up. So every thing that is 120 vac had better be unplugged or completely OFF so no standby loads to compete with the charger. If 120 vac air compressor comes on with the electric element, blown breaker. Good luck.
Plan B could be run the gen and keep fuel tank filled as needed till temp warms up or a 50 amp source is available.
The 4500 watt 240 vac element can run when there is a 50 amp two leg connection to the coach. The 1650 watt element runs on one of the two legs of this connection. Amp draw is near 37 amps.
When connected to 20 amp or 30 amp single leg connection, that leg is connected to both sides of the 240 element creating no potential difference across the element, so no current draw by that element. The 120 volt element is connected to the single leg and common or ground which has a potential difference and a current of about 13 or 14 amps will flow.
So if nothing else that has much of a current draw is ON, 20 amps will work. But, the burner and fans on the heating coils draw from the house batteries. The inverter charger has about 5 amps to use to keep the batteries up. So every thing that is 120 vac had better be unplugged or completely OFF so no standby loads to compete with the charger. If 120 vac air compressor comes on with the electric element, blown breaker. Good luck.
Plan B could be run the gen and keep fuel tank filled as needed till temp warms up or a 50 amp source is available.
Rudy Legett
2003 Foretravel U320 4010
ISM11 450 hp Allison 4000R
Factory Authorized Aqua Hot Repair Center
Southeast Texas Area