INSTALLER'S GUIDE
page 9
w
S
ENTHALPY
SENSOR
SPRAY SMALL AMOUNT OF COOLANT INTO UPPER
LEFT CORNER VENT OF ENTHALPY SENSOR
CASE TO SIMULATE LOW ENTHALPY
FOR CHECKOUT.
ENVIRONMENTALLY SAFE
COOLANT, SUCH AS
ENVI-RO-TECH 1672-10S
M12163
Checkout and Troubleshooting
Checkout Procedure for Single Sensor
Response
A. Make sure enthalpy sensor is connected to SO and +. The white
resistor must be placed on SR and +.
1. Turn enthalpy set point on Economizer Logic Module to “A”
1) LED (light -emitting
diode) turns on within a
minute.
2. With power connected, spray a small amount of envronmentally
safe coolant in upper left vent of sensor to simulate low enthalpy
conditions. (See figure 12)
2) Terminals 2, 3 closed.
Terminals 1, 2 open
B. Disconnect power at TR and TR1.
Terminals 2, 3 open.
Terminals 1, 2 closed.
A. 1. Turn enthalpy set point on Economizer Logic Module past “D”
(full clockwise).
1) LED turns off.
2. With power connected, spray a small amount of environmentally
safe coolant into upper left vent of sensor connected to SO and +
to simulate low outdoor air enthalpy. (See figure 12).
2) Terminals 2, 3 closed.
Terminals 1, 2 open.
B. Spray small amount of environmmentally safe coolant in upper left
vent of return air enthalpy sensor connected to SR and + to simulate
low return air enthalpy.
1) LED turns off.
2) Terminals 2, 3 open.
Terminals 1, 2 closed.
Checkout procedure for Differential Enthalpy
(Second enthalpy sensor connected to terminals “SR” and “+”)
