The unit is new to me and sitting on a stand in my shop with 4 feet of vertical vent for testing purposes. When I bought the heater four months ago and brought it home, I found the heat exchanger in bad shape, I have rebuilt the heat exchanger. When I first test fired the heater, it would not stay lit. I took a part, the burner assembly removed all the plugs from the aluminum manifold block, thoroughly cleaned the passages with bore brushes and solvent/Carb Cleaner, Reassembled with a 70371-service kit, new electrode, nozzle kits in both regulators and solenoids with all new O-rings. The pump will pull and hold a vacuum. The unit still shuts off about the time it has run long enough for the fan to come on. The electronic eye is disconnected for test purpose only, when I get the bugs worked out of the unit and mounted, I plan to hook it back up. The heater has what looks like a new 33400 , Oil Primary Control on it, the oil primary control goes to red when the unit shuts off, I’m not able to discern whether the unit goes to red and shuts off because the flame goes out, or if the unit is going to red and shutting off, causing the flame to go out. Could the oil primary control be bad causing my problem? With the eye disconnected what would cause the flame to go out?
