Hey all,
I'm trying to solve a problem with a brand new install of an Atwood AFMD35111 RV furnace. It's in a Tiny House, one certified as an RV. It was no 12v system, just AC so we purchased a 12v power converter rated at 20A to power the furnace. The furnace takes 11.1 amps according to the manufacturer.
When the thermostat trips, I can hear the blower try to start but then click off. It's like there's not enough power for it. If I trigger it multiple times, sometimes it will fire up then works perfectly. Basically, my theory is that hitting it a few times starts the blower spinning a little bit, so it needs less juice to get going when I trip it next. If I leave it a few minutes between tries, it won't fire up.
I've checked the sail switch, limit switch, talked to Atwood, talked to another tech, eliminated every other option. I've tested the thermostat, taken the thermostat out of the circuit and just bridged the wires, etc. Everything is fine except it not starting the blower. No blower = no ignition.
An interesting thing is that if i bypass the circuit board/breaker switch and apply 12v directly to the blower lead, it fires up no problem.
My theories: Something in the circuit board is drawing too much power, causing a voltage drop and triggering the breaker? Maybe the capacitor? Or maybe the board doesn't like the power supplied by the converter? It checks out as 12v with a multimeter. Drops to 10.7 when trying to fire up?!
I didn't have a 12v battery on site to test with, we use converters for everything.
Converter: https://www.amazon.ca/SunbowStar-Switch-Supply-Driver-Transformer/dp/B018DZQZ1Q/ref=sr_1_2?ie=UTF8&qid=1508769024&sr=8-2&keywords=12v%2B25a&th=1
Should be more than enough.
I'm stumped!
I'm trying to solve a problem with a brand new install of an Atwood AFMD35111 RV furnace. It's in a Tiny House, one certified as an RV. It was no 12v system, just AC so we purchased a 12v power converter rated at 20A to power the furnace. The furnace takes 11.1 amps according to the manufacturer.
When the thermostat trips, I can hear the blower try to start but then click off. It's like there's not enough power for it. If I trigger it multiple times, sometimes it will fire up then works perfectly. Basically, my theory is that hitting it a few times starts the blower spinning a little bit, so it needs less juice to get going when I trip it next. If I leave it a few minutes between tries, it won't fire up.
I've checked the sail switch, limit switch, talked to Atwood, talked to another tech, eliminated every other option. I've tested the thermostat, taken the thermostat out of the circuit and just bridged the wires, etc. Everything is fine except it not starting the blower. No blower = no ignition.
An interesting thing is that if i bypass the circuit board/breaker switch and apply 12v directly to the blower lead, it fires up no problem.
My theories: Something in the circuit board is drawing too much power, causing a voltage drop and triggering the breaker? Maybe the capacitor? Or maybe the board doesn't like the power supplied by the converter? It checks out as 12v with a multimeter. Drops to 10.7 when trying to fire up?!
I didn't have a 12v battery on site to test with, we use converters for everything.
Converter: https://www.amazon.ca/SunbowStar-Switch-Supply-Driver-Transformer/dp/B018DZQZ1Q/ref=sr_1_2?ie=UTF8&qid=1508769024&sr=8-2&keywords=12v%2B25a&th=1
Should be more than enough.
I'm stumped!