RGM 465, Mfg No. 175758, Page 33
General
Service
Reznor
®
used oil fired boilers have been designed and manufactured to
provide years of trouble free operation.
However, as with any type of mechanical equipment, it can malfunction.
For your safety, we suggest that if you are unfamiliar with servicing this
type of equipment, contact a qualified service person. The material con-
tained in this section is prepared to aid an experienced service person in
diagnosing problems and repairing the burner on a Reznor Model RAB
used oil boiler.
How the used-oil burner on a Reznor
®
Model RAB boiler operates
When service is necessary, it is always helpful to understand the operation
of the device being serviced. With this in mind, the following information
has been prepared. Because of the many unique features of the burner, we
as the designer and manufacturer believe that it will be worth your time to
read this information before beginning any service function.
This burner differs from the burner on most residential and commercial oil
furnaces and used oil heaters or boilers in that the oil pump meters the
volume of oil supplied to the burner. A constant volume of oil is delivered
by the pump to the burner regardless of the oil viscosity. Oil pressure at the
outlet of the pump will vary depending upon oil grade, the length and height
of the supply line, and the oil temperature.
If a pressure in excess of 50 psi is experienced at the pump, a relief valve
will open and return the oil to the supply tank.
Oil pressure at the atomizing nozzle will vary from .25 psi to 4 psi depend-
ing on the type of oil being burned. Nozzle oil pressure is not critical be-
cause compressed air is used to atomize the oil.
A solenoid valve and a check valve control the oil flow. The solenoid valve
located adjacent to the burner housing performs two tasks. The primary
task is to prevent oil from flowing into the combustion chamber due to oil
expansion in the heater. The second task is to assist in preventing oil from
flowing backwards. The check valve at the pump is used to prevent back-
wards flow of oil in both the heater supply line and the suction line to the
pump. Both the solenoid valve and the pump motor are turned on and off by
the ignition controller.
To properly atomize the different types of used oil, the oil must be heated.
The oil flows through an aluminum heat exchanger (pre-heater) with a heat-
ing element. Sizes 140 and 235 have a 300 watt element; Size 350 has a 650
watt element; and Size 500 has a 770 watt element. This oil heater which is
Burner
Operation
Service Notes
