Before you buy, ask how the burner is powered. Yes, perhaps you will save money on the initial purchase of a 12 volt system, but you will need the money you saved for the future repairs! 12 volt units draw their power to run the burner system from the battery. The engines diodes recharge the battery. The problem is that at times the diodes do not generate enough amps to keep up with the burner. As a result the fan motor slows down and the heating coils soot up from the lack of air flow. This huge engineering problem creates a mess and requires the coils to be cleaned more often. Vibration, operator controls, elevation, engine RPM all affect the engine diodes*. The pressure wash equipment we build all have their own separate generators – producing 115 volts to power the burner system! Obviously a 115 volt system with its own generator has 10 times the voltage and therefore is 10 times more reliable in operation.
*The 18HP unit utilizes a 12 volt burner and is NOT rated for continuous service.