Step 14 - Fan Speed Set Up; Units With Electro-Mechanical Controls - Carrier WeatherMaster 50GC 04-06 Series Installation Instructions Manual

Step 14 — Fan Speed Set Up

UNITS WITH ELECTRO-MECHANICAL CONTROLS

The fan speed set up controls are located on the lower section of
the Unit Control Board (UCB). See Fig. 53 for location.
1. Check the job specifications for the CFM (cubic feet per min-
ute) and ESP (external static pressure) required.
2. Using the chart on the fan speed set up labels (see Fig. 54),
calculate the Vdc from the CFM and ESP for the base unit.
Then add Vdc for any accessories installed per the "Field
Accessories" section of the label.
NOTE: The fan speed set up labels are located on the High Volt-
age cover in the Control Box.
3. Connect a multimeter to the Vdc terminals on the UCB.
4. Set the Range Switch to either A, B, or C per the Switch
Range table.
5. Using a straight blade screwdriver, turn the Vdc control dial
to fine tune the Vdc reading.
6. Record the reading in the Field Setting field.
NOTE: Fan set-up Vdc is not affected by the operating stage of
the unit.
Fig. 53 — UCB Fan Speed Controls
38
FAN SPEED SET UP CONTROLS