Honeywell Q674A-E - Manual (Page 11)

11 60-1165—6
Calibration
THERMOSTAT
T874 Thermostats are accurately calibrated at the factory.
They do not have provision for field calibration.
THERMOMETER
The thermometer in the thermostat has been accurately
calibrated at the factory. The thermometer should need ad-
justment only if it has been dropped or shifted due to mishan-
dling.
If the set point lever and the thermometer reading do not
agree, use the following procedure:
1. Remove the thermostat cover by pulling up from the
bottom of the cover until it clears the mounting slots.
2. Set the thermostat cover on a table near an accurate
thermometer.
3. Allow ten minutes for cover thermometer to sense area
temperature; compare the readings. Be careful not to touch
the thermometer or breathe on it.
4. If the readings are the same, replace cover and put the
system into operation.
5. If the readings are different, insert a small screwdriver
in the thermometer slot (Fig. 24) and turn it until the ther-
mometers have the same reading.
6. Replace thermostat cover and put the system into
operation.
NOTE: Hand heat will offset the thermometer reading.
After making each adjustment, wait ten minutes for the
thermometer to stabilize before comparing.
Fig. 24—Thermometer calibration.
M5070