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fused disconnect
for
pumps other
than
PumpPAKsrM).
When there is
a
call for
an
M1
output
from
the
controller,
the
contactor
will
energize, starting
the
compressor
and
earth
loop pump.
3. Compressor
Operation
A Y
signal
from
the
thermostat
will tell
the
controller
to
initiate
forced air heating or
cooling.
The
controller
then
decides, based
on lockouts, anti-short-cycle periods,
and
priorities,
when to
bring
the
compressor
on.
The
Ml
output
of
the
controller
energizes the
compressor. The
compressor
stays
on
until
either
the
thermostat
is
satisfied,
the aquastat
calls
for hydronic
heating
with
hydronic
priority,
or
a
lockout condition
occurs.
An H
signal
from
the aquastat
will
tell
the
controller
to
start
in
hydronic heating
mode.
Depending
on
lockouts,
anti-short-cycle periods
and
priorities,
the
controller
will
send
an
Ml
signal to
start the
compressor. The
compressor
will
stay
running in hydronic
mode
until
the
aquastat
is satisfied,
the
thermostat calls
for
forced
air
heating
or cooling with
forced air
priority,
or
a
lockout
condition
occurs.
4.
4-Way Valve
Control
The
conffoller
energizes the
4-way reversing valves to
direct
the
flow
of
refrigerant. When
the
unit
is running
in
forced air
cooling,
the
controller
energizes
its
M3
output
to
send
control
power to
fhe
cooling
reversing valve
(VRl),
to
switch
the
refrigerant
circuit
to
the
cooling
mode.
When
the
unit
is
running in hydronic
heating
mode, the
controller
energizes
its
M4
output
to
send
control
power
to
the
hydronic reversing valve
(VR2), to
switch
the
refrigerant
circuit
to
the
hydronic
mode.
5. Compressor Lockouts
A
compressor
lockout
occurs
if
the
high-pressure,
low
pressure,
or
freeze
protection
pressure
switches
open.
The
controller
blocks
the
signal
from
the
thermostat
or
aquastat
to
the
contactor that
normally would
energize the
compressor.
In
the event
ofa
compressor
lockout
the
controller
will
send
a
signal
from
L
on
the
terminal
strip
to
an
LED
on
the
thermostat to indicate
a
lockout
condition.
On GeoSource
DuaITEK
units,
if
the heat
pump locks out
in
either
the
forced air or hydronic mode,
the
controller
will
let
the
other
mode
run
until
that mode
also
locks
out.
For example,
if
a
problem
with
the
hydronic loop
causes
the heat
pump to
lock
out
on one
of
the pressure
switches,
the heat
pump
will still
be able
to
run
in
forced air
mode.
If
the heat
pump then locks
out
while
it
is
in
the
forced air mode.
the
unit
will
not come
on
in
either
mode.
A
lockout condition
means
that
the
unit
has shut
itself
down to protect
itself.
The
unit
will
have
to be
shut
off
at
the
circuit
breaker
for
one
minute to
reset the
controller.
Problems that could
cause
a
lockout
situation include:
a.
Water
flow
or
temperature problems
b.
Air flow
or
temperature problems
c.
Internal
heat
pump operation problems
d.
Cold
ambient air temperature conditions
tlf
a
lockout
condition
exists,
the heat
pump should
not
be reset
more
than
once;
a
service technician should
be
called
immediately.
9The
cause
of
the
lockout
must
be
determined.
Repeated reset
may
cause damage
to
the
system.
6.
Compressor
Anti-Short-Cycle
An
anti-short-cycle is
a
delay period between
the
time
a
compressor
shuts
down
and
when
it
is allowed to
come
on
again.
This protects
the
compressor
and
avoids nuisance
lockout conditions. Anti-short-cycles
occur after
these
four
conditions;
l)
A
one
to
two
minute
time-out
period
occurs
on
the compressor
before
it
will
start after its last
shutdown.
2)
A
four
minute
35 second
delay is incorporated
into
the
timing function immediately
after power
is applied to
the heat
pump. This
occurs
only
after reapplying power to
the
unit.
To
avoid this
timeout
while
servicing
the
unit,
apply power,
disconnect
and
reapply power very
quickly.
This
can sometimes
eliminate
the
waiting
period.
3)
A
30
second
to
one
minute anti-short-cycle
will
occur after
a
low-pressure switch
opens
in
the
cooling mode.
This is
done
to eliminate
nuisance
lockout conditions.
If
the
compressor
continuously
short cycles
in
the
cooling
mode,
shut the
thermostat
off
and
call
your service
technician.
4)
A
one
to
two
minute anti-short-cycle occurs
when switching between forced air
and
hydronic
modes.
7. System
Diagnostics
The
controller
is equipped
with
diagnostic
LED lights
which
indicate
the system status at any
particular
time.
The
lights
indicate
the
following
conditions:
a. 24Yolt
system
power
GREEN
b.
Faultorlockout
RED
c. Antishort-cycle
mode
RED
d.
Forced
Air
Compressor
operation
RED
e.
Hydronic
Compressor
operation
RED
f.
Pressure
switch
status
on
lockout YELLOW
g.
controller
outputs
(Ml
thru
M10)
RED
h.
Condensate
overflow
(optional)
RED
8.
Forced
Air/Ilydronic Priority
Dip
Switch #1 on
the
controller
decides
forced
airl
hydronic
priority.
When
the
dip
switch is
in
the
ON
position
(factory preset),
the
forced air
mode
has
priority
over
hydronic mode. This
means
that
if
the heat
pump is
running
in
the
hydronic
mode, and the
thermostat gives
a
16
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