Install Instructions
5
In order to diagnose the cause of problems in this system it is
necessary to determine certain values. It is helpful to have a
volt/ohm multimeter.
Modulation Function: If sensed temperature (controller display)
is less than minimum dial setting temperature, perform Step A
below, otherwise continue on to Step B.
A. Disconnect the sensor wires to terminals (amplifier - 8 and
9, amplifier/selector - 1 and 2) and replace with supplied test
resistor or with other means to obtain a resistance value falling
within the temperature range to be tested, referencing
temperature table below.*
B. Connect a DC volt meter to terminals 3 and 4, or at the M/
MR valve terminals. Do not disconnect existing wiring.
C. Rotate temperature
dial knob to maximum
setting - the DC volts
should read at least 17.5V
DC. Rotate temperature
dial knob to minimum
setting - the DC volts
should read no more than
2.0V DC. DC voltage
should gradually increase
as the dial temperature
setting is slowly rotated up
to and past the controller's
digital display
temperature.
Override Function:
(Amplifier w/Remote
Selector, 40
o
-90
o
F range,
ONLY)
Temperature TableTemperature Table
Temperature TableTemperature Table
Temperature Table
*Approximate controller display temperature with 1100 to 1800
ohms resistance across terminals (amplifier - 8 and 9, amplifier/
selector - 1 and 2).
R (ohms) T (degrees)
1100 78
o
F (25
o
C)
1200 125
o
F (50
o
C)
1300 172
o
F (80
o
C)
1400 220
o
F (100
o
C)
1500 270
o
F (130
o
C)
1600 315
o
F (160
o
C)
1700 365
o
F (185
o
C)
1800 410
o
F (210
o
C)
M Valve: Regulator upstream of modulatorM Valve: Regulator upstream of modulator
M Valve: Regulator upstream of modulatorM Valve: Regulator upstream of modulator
M Valve: Regulator upstream of modulator
valvevalve
valvevalve
valve
Typical Gas Trains
A. Connect a DC volt meter to terminals 3 and 4, or at the M/MR
valve terminals. Do not disconnect existing wiring.
B. Connect a jumper between terminals 11 and 12 - the
approximate volts should read at least 17.5V DC.
Automatic Valve Function: (Indirect Fired units ONLY) If sensed
temperature (controller display) is less than minimum dial setting
temperature, perform Step A below, otherwise continue on to
Step B.
A. Disconnect the sensor wires to terminals (amplifier - 8 and 9,
amplifier/selector - 1 and 2) and replace with supplied test
resistor or with other means to obtain a resistance value falling
within the temperature range to be tested, referencing
temperature table below.*
B. Disconnect wires to terminals 5 and 6. Connect an
ohmmeter to the terminals
(use a voltmeter for remote
system amplifier model
A1094).
C. Rotate temperature dial
knob to maximum setting.
Volt/ohmmeter should
indicate continuity. Rotate
temperature dial to
minimum setting. Volt/
ohmmeter should indicate
open circuit.
Temperature Sensor
Function: Perform the
entire "Modulation
Function" analysis,
implementing Step A. (Step
A isolates the sensor
function from the system)
Preliminary Circuit Analysis
MR Valve: Modulator-regulator valveMR Valve: Modulator-regulator valve
MR Valve: Modulator-regulator valveMR Valve: Modulator-regulator valve
MR Valve: Modulator-regulator valve