PAGE 6 of 61 HO-7-1237 & HO-4-1234 OIL-FIRED HEATERS
© SAMUEL JACKSON, INCORPORATED 2003 ALL RIGHTS RESERVED
HOW DO I SET THE TEMPERATURE?
The temperature is set using the UP ARROW and DOWN ARROW buttons on the left
digital temperature controller on the 20000 Temperature Control (Figure 3) located at the
remote control station. The left controller is called the PRIMARY TEMP
CONTROLLER (After-Mix Temp). The controls must be energized before the
temperature can be changed. The last temperature set and held for one minute is
remembered by the controller.
As the temperature is changed on the left controller, this action will cause the HIGH
LIMIT CONTROLLER (Before-Mix Temp) on the right to respond. The HIGH LIMIT
CONTROLLER insures that the burner operates within a temperature range that is safe
for the product being dried (for example, 350
0
F, 177
0
C, is normally the high
temperature limit for cotton fiber).
There are two temperatures displayed on each controller during burner operation. The
bottom number is the desired temperature. It is called the setpoint temperature (SP). The
top number is the measured temperature. It is called the process variable (PV).
Both of the controllers have arrow buttons. In addition, both controllers have a button
marked SETPOINT SELECT. To bypass the modulating high limit setting, press the
SETPOINT SELECT button and use the arrow buttons to set the desired temperature.
The letters RSP (for remote setpoint) preceding the setpoint temperature will be replaced
with the letters SP when the SETPOINT SELECT button is pressed. The operation of the
automatic shutdown high temperature limit is preserved even when the modulating high
limit setting is bypassed.
Pressing SETPOINT SELECT button again will put the controller back into RSP mode.
A bright rectangle will appear on the left of the control display indicating when the
Figure 3 - 20000 Temperature Control
14-3567.2
