Zone
Zone
SEQUENCE OF OPERATIONS
Pioneer Gold 1.10 & 2.05 Controller Technical Guide
1-28
Thermostat Controlled Compressor, Reversing Valve, Electric Heat
Compressor Operation
Unless an alarm is active, the compressor will enable upon receiving
a 24VAC input on the “Y1” terminal or upon receiving a 24VAC
input on the “TH_NS” terminal if in Night Setback Mode. The
water valve/pump terminal will energize right away when the input
is received into “Y1”. If the Supply Fan was not enabled prior to
the compressor call, then the Supply Fan will enable for 5 seconds
before the compressor is started.
Compressor staging up and staging down are subject to the following
setpoints:
•
Compressor On Delay
(5 seconds, non-adjustable)
•
Compressor Minimum On Time
(default: 180 seconds; range: 120-255 seconds)
•
Compressor Minimum Off Time
(default: 120 seconds; range: 60-255 seconds)
•
Compressor Interstage On Delay
(default: 60 seconds; range: 30-255 seconds)
•
Compressor Interstage Off Delay
(default: 60 seconds; range: 30-255 seconds)
If the unit goes into an alarm, the minimum on time of the
compressor(s) will be ignored and the compressor(s) will be disabled.
All alarms will disable the compressor(s).
Reversing Valve Operation
For a single stage compressor, the Reversing Valve will enable if
the controller receives a 24VAC input on the “O” terminal and the
compressor has been operational for a minimum of 5 seconds. This
delay allows the difference in line pressures to assist the Reversing
Valve in changing positions. Once the compressor call is removed,
the Reversing Valve will be reset, and (1 second later) the compressor
will be disabled.
For a Single Compressor 2-stage application, when the first
compressor stage “Y1” is called for and the reversing valve in
the opposite state required, the compressor will first enable at full
capacity “Y2”, and after 5 seconds, the reversing valve will change
positions. Following an additional 3 seconds, the compressor will
stage down to “Y1” operation.
The default Reversing Valve position is for heating operation, no
24VAC input on the “O” terminal. Therefore, in compressor cooling
operation, 24VAC must be applied to the “O” terminal.
Electric Heat Operation
External Duct Heater(s)
The W1 Heat Output is designed to be used with duct heaters. The
W1 heat output will be enabled whenever the W1 input has 24VAC
applied to it. The duct heaters will provide any staging, delays,
and safety protections required. The Electric Duct Heater Setpoint
must be set to ON.
Integral Electric Heat (Electric Heat Board)
Integral Electric Heat Inputs and Outputs will be contained within
an expansion module. The Integral Electric Heat setpoint must be
set to ON. Whenever the W1 input has 24VAC applied to it, the
heat stages will enable and disable according to its interstage delays.
Waterside Economizer Operation
(WSE)
On/Off Waterside Economizer (WSE)
Coil Operation
In this operation, the Waterside Economizer (WSE) can be
configured for four modes:
Off
– Default. No condenser water loop function.
Cool Only
– WSE Valve cycles ON based on Cooling
Entering Water Temperature Setpoints.
Heat Only
– WSE Valve cycles ON based on Heating
Entering Water Temperature Setpoints.
Dual
– WSE Valve cycles ON based on Entering Water
Temperature Setpoints of corresponding mode demand.
Cool Only Operation
The WSE will act as the unit’s first stage of cooling. As the Entering
Water Temperature drops below the Cooling Entering Water
Temperature Setpoint (default: 45°F, range: 45-60°F), the call for
the compressor, if enabled, will be removed once the minimum
on time has been satisfied, and the WSE 24VAC output will be
enabled, sending the cold loop water through the air coil to utilize
“free cooling”. Once the Entering Water Temperature rises above
the Cooling Entering Water Temperature Setpoint plus the deadband
(2.5°F, non-adjustable), the WSE will be disabled, and compressor
cooling will be utilized following a 60 second delay.
If the cooling call has not been satisfied within a user-adjustable time
in minutes of operation (default: 10 minutes; range: 10-255 minutes),
the WSE Valve will disable. Following a 60 second delay, the unit
will resume normal compressor cooling operation until the cooling
input is removed. When this happens, the display will signify the
WSE was unable to meet the cooling call.
For Freeze Protection, the Entering Water Temperature will be
monitored.
