FHP GO024 Installation And Maintenance Manual - page 5
5
GO SERIES
point for thermostat wiring, the interface board also
translates thermostat inputs into control commands for
the variable speed programmable ICM-2 DC fan motor
and displays an LED indication of operating status. The
t h e r m o s t a t c o n n e c t i o n s a n d t h e i r f u n c t i o n s a r e a s
follows:
Y2
Second Stage Compressor Operation
Y1
First Stage Compressor Operation
G
Fan
O
Reversing Valve (energized in cooling)
W1
Auxiliary Electric Heat
(runs in conjunction with compressor)
EM/W2
Emergency Heat (electric heat only)
NC
Transformer 24 VAC Common
(extra connection)
C1
Transformer 24 VAC Common
(primary connection)
R
Transformer 24 VAC Hot
HUM
Dehumidification Mode
(not used in GO Series)
If the Geo-Miser unit is being connected to a thermostat
with a malfunction light, this connection is made at the
unit lockout relay.
NOTE:: If the thermostat is provided with a malfunction
l i g h t p o w e r e d o f f o f t h e c o m m o n ( C ) s i d e o f t h e
transformer (such as FHP’s part # 641-068), the unit
must be provided with a malfunction relay (FHP option #
660-006) to properly energize the light. The relay coil will
be wired across the (ALR) and (C) contacts on the unit’s
C C M b o a r d a n d t h e r e l a y ’ s n o r m a l l y o p e n c o n t a c t s
across (ALR) and the malfunction light connection on the
t h e r m o s t a t . I f t h e t h e r m o s t a t i s p r o v i d e d w i t h a
malfunction light powered off of the hot (R) side of the
t r a n s f o r m e r ( s u c h a s F H P p a r t # 6 4 1 - 0 6 0 ) , t h e n t h e
t h e r m o s t a t m a l f u n c t i o n l i g h t c o n n e c t i o n s h o u l d b e
connected directly to the (ALR) contact on the unit’s
CCM board.
To the left of the thermostat connection block are a row
of 2 red and 4 green LED’s. These LED’s indicate the
operating status of the unit. They are labeled as follows:
EM
(red)
Emergency Heat On
W1 (red)
Auxiliary Heat On
O
(green)
R e v e r s i n g V a l v e E n e r g i z e d , u n i t i s i n
cooling mode
Y2
(green)
Second Stage Compressor On
Y1
(green)
First Stage Compressor On
G
(green)
Fan On
Just above the connector block is a single red LED
labeled CFM that will blink intermittently when the unit is
running and may flicker when the unit is off. This LED
indicates the air delivery of the blower at any given time.
Each blink of the LED represent 100 CFM of air delivery
so if the LED blinks 12 times, pauses, blinks 12 times,
etc. the blower is delivering 1200 CFM. Refer to Figure
#7 for factory programmed air delivery settings for the
GO Series.
To the right of the thermostat connection block is a green
LED labeled dehumidify. This feature is not utilized on the
GO Series.
Just above and to the right of the thermostat connection
block are four sets of jumper pins labeled ADJ, DELAY,
HEAT and COOL. The ADJ set of pins are labeled NORM,
(+), (-) and TEST. GO units will all be set on the NORM
p o s i t i o n f r o m t h e f a c t o r y , h o w e v e r , a i r f l o w c a n b e
increased (+) or decreased (-) by 15% from the pre-
programmed setting by relocating the jumper in this
section. The TEST position is used to verify proper motor
operation. If a motor problem is suspected, move the
ADJ jumper to the TEST position and energize G on the
thermostat connection block. If the motor ramps up to
100% power, then the motor itself is functioning normally.
Always remember to replace the jumper to NORM, (+) or
(-) after testing and reset the unit thermostat to restore
normal operation.
NOTE: Do not set the ADJ jumper to the (-) setting when
electric heaters are installed. Doing so may cause the
heaters to cycle on their thermal overload switches,
potentially shortening the life of the switches.
The other three sets of jumper pins are used to select the
proper program in the ICM motor for the unit. Refer to
Figure #7 for the proper jumper placement.
N O T E : A l w a y s d i s c o n n e c t p o w e r b e f o r e c h a n g i n g
jumper positions on the interface board and reset the unit
afterward.
To the left of the red and green status LED’s is a row of
1 / 4 ” m a l e q u i c k c o n n e c t s . T h e s e a r e u s e d t o p a s s
thermostat inputs on to the rest of the control circuit.
Remember to always turn off unit power at the circuit
breaker before attaching or disconnecting any wiring from
these connections to avoid accidental short circuits that
can damage unit control components.
SAFETY DEVICES AND THE LOCKOUT CIRCUIT:
E a c h G o S e r i e s u n i t i s f a c t o r y p r o v i d e d w i t h a h i g h
pressure switch, low pressure switch and a condensate
overflow switch. These switches are all normally closed,
opening on a fault condition. If either the high pressure
switch or the condensate overflow switch open, the unit
compressors will shut down immediately. Note that the
blower motor and electric heaters will remain active. The
low pressure switch is deactivated for 90 seconds after
compressor start-up by the low pressure bypass timer.
This prevents nuisance low pressure lockouts during cold
MOTOR PROFILE AIR FLOW TABLE
FAN
LOW
HIGH
AUX. EMERGENCY COOL
MODEL ONLY
STEP
STEP
HEAT
HEAT
HEAT
AIRFLOW
DELAY ADJUST
GO024
550
–
800
900
900
B
NORM
GO030
700
–
1000
900
900
A
NORM
GO036
850
–
1200
1150
1150
A
NORM
GO042
1000
–
1400
2000
2000
D
NORM
GO048
1050
1100
1600
2000
2000
C
NORM
GO060
1100
1400
2000
2000
2000
B
NORM
GO072
1600
1600
2200
2200
2200
A
NORM
(Figure #7)