Carrier WeatherMaker 50TCQ07 Installation Instructions Manual

Also see for WeatherMaker 50TCQ*07: Product data

20UNIT WITHOUT THRU-BASE CONNECTION KITPass the thermostat control wires through the hole provided inthe corner post; then feed the wires through the raceway builtinto the corner post to the control box. Pull the wires over tothe terminal strip on the upper-left corner of the Central Termi-nal Board. See Fig. 32.NOTE: If thru-the-bottom connections accessory is used, refer tothe accessory installation instructions for information on routingpower and control wiring.Fig. 32 — Field Control Wiring RacewayHEAT ANTICIPATOR SETTINGSSet heat anticipator settings at 0.14 amp for the first stage and0.14 amp for second-stage heating, when available.Central Terminal BoardThe Central Terminal Board (CTB) is a pass through connec-tion point. The CTB provides the capability to add factory-in-stalled options and field-installed accessories to the units bycutting jumper wires without having to change or reroute wiresthrough the structure of the unit. The CTB does not provideany microprocessor control; it is simply a basic multifunctionwiring terminal configuration.Commercial Defrost ControlThe Commercial Defrost Control Board (DFB) coordinatesthermostat demands for supply fan control, 1 or 2 stage cool-ing, 2 stage heating, emergency heating and defrost controlwith unit operating sequences. The DFB also provides an in-door fan off delay feature (user selectable). See Fig. 33 forboard arrangement.Fig. 33 — Defrost Control Board ArrangementThe DFB is located in the 50TCQ unit’s main control box (seeFig. 34). All connections are factory-made through harnessesto the unit’s CTB, to IFC (belt-drive motor) or to ECM (direct-drive motor), reversing valve solenoids and to defrost thermo-stats. Refer to Table 6 for details of DFB Inputs and Outputs.REVERSING VALVE CONTROLThe DFB has two outputs for unit reversing valve control. Op-eration of the reversing valves is based on internal logic; thisapplication does not use an “O” or “B” signal to determine re-versing valve position. Reversing valves are energized duringthe cooling stages and the defrost cycle and de-energizedduring heating cycles. Once energized at the start of a coolingstage, the reversing valve will remain energized until the nextheating cycle demand is received. Once de-energized at thestart of a Heating cycle, the reversing valves will remain de-en-ergized until the next cooling stage is initiated.COMPRESSOR CONTROLThe DFB receives inputs indicating Stage 1 Cooling, Stage 2Cooling and Stage 1 Heating from the space thermostat or unitcontrol system (PremierLink™ controller or RTU Open con-troller); it generates commands to start compressors with orwithout reversing valve operation to produce Stage 1 Cooling(one compressor runs), Stage 2 Cooling (both compressors run)or Stage 1 Heating (both compressors run).Fig. 34 — Defrost Control Board LocationRACEWAYHOLE IN END PANEL (HIDDEN)DIPSwitchesSpeed-UpJumpers