C E N T R I F U G A L H E A T E R - C S A
Chief Industries, Inc. 800-359-7600 OPERATION - 416274
Page 30
Adjustments:
The following adjustments will have to be made, depending upon the kind of heater and plenum
external controls being used. These adjustments cannot be made at the factory due to the differences in
bin setups, drying methods, and weather climates. These adjustments should be checked at least twice a
day or every 6 hours of operation to verify that the heater is functioning properly, and that the desired
results are being achieved. In using the recommended drying temperatures keep the following
considerations in mind:
Vaporizer Adjustment
The vaporizer is used on LPGE units and is located in the flame established by the burner. The
vaporizer uses heat from the burner to convert the liquid propane at the vaporizer entrance to vapor
propane. The burner requires vapor propane for proper operation.
The vaporizer outlet is connected to the vapor plumbing line by a vapor propane hose. The
temperature of the vapor plumbing line is sensed by a vapor limit thermostat, which will cycle the heater
off if the temperature exceeds 160°F (71°C). The proper location of the vaporizer will establish a vapor
plumbing line temperature of about 110°F (43°C). At this temperature, the vapor plumbing line should
be warm to touch. If the temperature of the vapor plumbing line is too low, move the vaporizer into
the flame by loosening the square headed setscrew holding the vaporizer in place, adjusting the
vaporizer location and re-tightening the setscrew. If the temperature of the vapor plumbing line is too
high, the vaporizer should be moved out of the flame with the procedure indicated above.
Regulator Adjustment
The regulator should be set at the firing rate required. This can be done by first setting the heater to the
desired firing rate with the vapor valve, then reopening the vapor valve and adjusting the regulator by
turning the adjusting screw until the pressure gauge shows the desired pressure at the desired firing rate.
When setting the heater at the desired firing rate, the operator must take into account the heater size,
the static pressure the fan is working against, the ambient temperature, orifice size, and fuel used and
the type of plenum control. Refer to operation instructions that are supplied with the humidistat,
thermostat, or modulating valve. The
of this manual are set up to help the operator
select the desired firing rate.
Humidistat Control Adjustment (Heater Operation)
Set the humidistat control at the desired setting (50% - 60% relative humidity is recommended). To
obtain even drying, adjust the firing rate of the heater unit so that the humidistat maintains a constant
humidity of the drying air. The heater should be set at a firing rate of approximately 2 psig (14kPa) for
propane, or 1 psig (7kPa) for natural gas, and then be adjusted to maintain correct operation of the
heater. The heater firing rate must be checked as humidity conditions change.
Thermostat Control Adjustment (Heater Operation)
