Operation
Compressor operation
Compressor operation includes the following features:
1. Compressors are controlled by the Y1 through a maximum of Y4 thermostat inputs.
CAUTION
As lead-lag function must be turned OFF, Y1 input energizes the C1 output when the compressor #1
ACSD is at 0 and all refrigerant safety devices are closed (default 5 minutes).
2. The fan output for indoor fan operation energizes with any cooling output after the indoor
fan cool on delay expires.
3. When the thermostat cooling inputs are lost and the minimum runtime expires, the
compressor outputs stage off (the default is 3 minutes).
4. A 30 second interstate delay occurs when multiple stages are requested.
5. Here is the sequence of operation for a four stage unit:
- Y1 energizes Compressor 1 stage 1
- Y2 energizes Compressor 2 stage 1
- Y3 energizes Compressor 2 stage 2
- Y4 energizes Compressor 1 stage 2
6. Here is the sequence of operation for a three stage unit:
- Y1 energizes Compressor 1 stage 1
- Y2 energizes Compressor 1 stage 2
- Y3 energizes Compressor 2
IntelliSpeed™ supply fan control
Setpoints and related data are shown in Table 26.
Table 26: Setpoints and related data
Stages
Fan control type
Fixed
Occupied, no heat or cool % command
50%
Occupied, one stage of cool % command
50%
Occupied, two stage of cool % command
60%
Occupied, three stage of cool % command
75%
Four stage
Occupied, four stage of cool % command
100%
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D-Series Vertical (DSV060C-300C) Air-Cooled Self-Contained Units, C Generation with Smart Equipment Controller
Johnson Controls
