OMEGA-VSHPe.F-IOM-2205
12
ultra low fan speed air circulation.
Whisper Mode
Whisper mode is factory enabled and runs main blower
fan at pre
-
determined low fan speed for continuous air
circulation. A jumper is factory installed between
‘
R
’
and
‘
G1
’
terminals on TB1 of control board to enable Whis-
per mode. With Whisper Mode DIP Switch #6 is set to
(ON) Auto. The manual fan speed switch is not used.
Single Fan Speed Thermostat
If connecting thermostats with single fan speed control
connect fan speed to either the G2, or G3 terminals:
G1 =
“
Whisper
”
Mode
G2 = MEDIUM fan speed
G3 = HIGH fan speed
(Do not wire thermostat fan to G1 terminal)
Multi Fan Speed Thermostat
Up to two fan speeds can be selected from a multi
-
speed thermostat. Connect two of the thermostat fan
speeds to the G2, and G3 terminals:
G1 =
“
Whisper
”
Mode
G2 = MEDIUM fan speed
G3 = HIGH fan speed
(Do not wire thermostat fan to G1 terminal)
Fan Control with EC Motors (ECM)
Low voltage PULSE WIDTH MODULATED (PWM) sig-
nal is utilized to control motor speed between 0 and
100% of full speed. The controller has been pro-
grammed to use 3 preprogrammed speeds for
“
Whisper
”
Mode, Medium and High speed. Inside electrical box a
label indicates the factory pre
-
programmed speed set-
tings.
SEQUENCE OF OPERATION
Call for Heating and Cooling
When a compressor request is made, the optional mo-
torized auto shut
-
off control valve will open. The com-
pressor contactor will then be energized so long as none
of the following fault conditions are present:
•
High
-
Pressure Alarm
•
Low
-
Pressure Alarm
•
(Optional) High
-
Pressure Water Alarm
•
(Optional) Condensate Over Flow Alarm
•
Compressor Anti
-
Short Cycle 7 min. timer expired
•
(Optional) Entering Water Temperature (EWT) is
greater than 115oF
•
(Optional) Leaving Water Temperature (LWT) great-
er than 127oF
When call for compressor request is terminated, the
optional motorized auto shut
-
off control valve and the
blower fan will remain open until the timers have ex-
pired.
Low
-
Pressure Bypass
During a call for compressor, the low
-
pressure switch is
bypassed for the first 3 minutes of compressor operation
to prevent nuisance low
-
pressure start
-
ups.
Timers and Interlocks
Microprocessor board utilizes a number of timers and
interlocks in the control sequence of the unit.
Anti
-
Short Cycle Timer
The compressor anti
-
short cycle timer of 7 minutes
starts every time a call for compressor is terminated to
prevent compressor over cycling.
Fan
-
On/Off Timer
The Fan
-
On timer of 10 seconds starts anytime there is
a call for fan request and 10 seconds after a call for
compressor is terminated.
Valve Open/Closed Timer
The valve open timer of 1 minute starts anytime a fan
and compressor request are made to develop flow in the
water coil. The valve closed timer of 1 minute starts any-
time a call for compressor is terminated to allow for
flushing of the water coil.
Random Wait Time on Unit Power Up
Microprocessor controller uses a random wait time dur-
ing unit start up between 1
-
30 seconds.
