CAA HOC045C3AB Installation manual

Installation, Start-up
and
Service Manual
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CONTENTS
I. SafetyConsiderations
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II. Start‐Up
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III. Pre‐installation
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IV. Installation
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V. SplatLT2Controller
Generaldescription
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VI. LT2ControllerLayout&Functions
a. Speedup
b. SetupMenu
c. DashBoardScreens
d. IdleScreen
e. FaultHistory
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VII. TroubleShooting
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VIII. Service/Maintenance
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IX. Installationdrawing
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X. Wiringdiagrams
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XI. Specificationsheets
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XII. Testinformationpage
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XIII. Appendeddataforoptionunits(Optional)
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Horizontal Split Air
Conditioners
2 stage designs
with
Splat LT2 Controllers
Page 1 of 42
IM-HOA 2 ST Rev 2.0 - 21/07/2013

I. SAFETY CONSIDERATIONS
Before installation, please read carefully these precautions and warnings for safety.
The unit is designed to provide safe and reliable service when operated within design specifications.
To avoid injury to personnel and damage to equipment or property when operating the equipment, the
following safe practices should be observed as a minimum.
Check the unit weight to be sure the lifting equipment is adequate.
Disconnect power to the unit before working on it.
Do not remove access panels or doors until fans have completely stopped.
Do not enter an enclosed fan cabinet or into the unit while a fan is running.
Protect materials when welding or flame cutting. Use suitable cloth to contain sparks.
Have a fire extinguisher at hand and ready for immediate use.
To be installed by qualified persons only.
Turn off main power supply before attempting any electrical work. Make sure all power
switches are off. Failure to do so may cause electric shock.
Connect the connecting cable correctly. If the connecting cable is connected wrongly,
electric parts may be damaged. Check the earth wire for continuity.
Do not install near concentrations of combustible gas or gas vapours to avoid possible
explosion.
Never modify this unit by removing any of the safety guards or bypassing any of the safety
switches.
Make sure to conduct a trial operation after the installation work, and explain how to use
and maintain the unit to the customer in accordance with the manual. Ask the customer to
keep the installation manual safe with the unit.
II. Pre-installation
Check items received against delivery note. Examine unit for damage which may have occurred in
transit. Notify the manufacturer’s sales representative of any damage. Remove packaging from unit and
any protective foam packing from coils and pipes. Each air-conditioning unit has a Product
Identification Plate mounted externally and a second one mounted inside the electrical compartment. A
typical identification plate is shown below. Refer to the Product Identification Plate mounted on the
unit for generalized technical information.
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Product Identification Plate
Page 2 of 42
IM-HOA 2 ST Rev 2.0 - 21/07/2013

III. Installation
1. Location
The equipment must be installed in accordance with relevant authority requirements.
Position the unit on a solid, level mounting pad ensuring adequate service access as outlined on
the Installation Drawing attached. Level and fasten the units, making sure that access panels
close easily and are able to be removed. Connect all necessary ducting.
2. Drains
An adequate drain line trap must be provided outside the indoor coil for condensate run-off. The
drain pipe should be installed with a continuous downward grade away from the unit. The gradient
should not be less than 1:50. Outdoor units operating on reverse cycle will release water from
the outdoor coil as well, particularly during defrost. Where appropriate, water should be drained
to waste.
3. Refrigeration piping and charging
The system is factory charged with dry Nitrogen. This is discarded to atmosphere before
beginning the pipe installation.
Always use new, clean and sealed refrigeration grade copper tube.
Always keep refrigeration pipe ends capped while working with it.
Make sure to pass a slow steady stream of dry Nitrogen through pipes as they are welded, as
the brazing process produces oxidized scale which can block valves and driers at a later
date if not removed.
Use shields to prevent paint damage from welding flames. Wrap valves in wet rags prior to
welding near them.
Pipes should be suspended with industry standard hangars. Be sure to consider pipe
expansion/contraction when laying pipework out.
It is not normally necessary to insulate liquid line pipes, unless it is run in areas of
hot Sun, ceiling voids or underground. Suction pipes will need to be insulated to industry
standard.
Pipe runs greater than 30 m should be checked for higher than normal refrigerant pressure
drop.
Height differences greater than 10 m between indoor and outdoor units must be piped in line
with industry standard, This might for example include the use of solenoid valves, trapping
and in some instances the use of double risers.
Once the piping has been welded in place, pressurize the system to 1000 kPa with dry
Nitrogen and check it for leakage. Once piping is sound, pull a vacuum simultaneously from
the high and low sides of the compressor, down to 10 micron or better.
The system is now ready to be charged with a fresh charge of R410a refrigerant. Always
charge the system with liquid refrigerant only. This ensures the refrigerant blend amounts
are retained while transferring refrigerant from bottle to system. Do not use pre-used
refrigerant as the blend is not guaranteed.
Connect the refrigerant bottle through a manifold set and weigh in on the compressor
discharge side only. The following amounts provide a guide depending on the unit being
charged:
45/55 kW units 7 kG
65/75 kW units 11 kG
90/100 kW units 15 kG
115/120 kW units 17 kG
It is not critical that the above amounts are entered into the system. If the amount
weighed in is within 10 to 15% of the above values, it should be sufficient to ensure the
LP sensor contact has been made. Make a note of the exact amount of refrigerant weighed in
to the unit to date.
When charging, do not use the last approximately 3 to 5% refrigerant in the charging
bottle. Again, it is because R410a is a blend, and it cannot be guaranteed that the blend
is maintained in this last amount.
Leave the charging manifolds and refrigerant bottle connected to the system, with the
manifold valves completely closed. This is a good time to make sure sufficient residual
refrigerant remains in the charging bottle so that trimming of charge is able to be carried
out once the system is running.
WARNING: To minimise oxidation inside copper tubing, all brazing operations must be completed
with a small steady stream of nitrogen passing through the pipework to be welded.
VERY IMPORTANT: Never use the compressor as a vacuum pump. Do not overcharge with refrigerant.
Page 3 of 42
IM-HOA 2 ST Rev 2.0 - 21/07/2013

4. Electrical
All electrical work must be carried out by a qualified and licensed electrician. The installation
must comply with the current relevant standards wiring rules and local authority requirements.
Wire sizing is the responsibility of the installer, as it depends on the conditions and
regulations applicable to each installation site. Refer to the electrical drawing and
specification of the unit for the electrical data. The electrical installation requirements are
generally as follows:
The air-conditioning unit shall be supplied directly from a distribution board through a
mains lockable isolating switch.
Ensure that power supply phase rotation is correct.
Control circuit has been designed to be powered from a low voltage 24VAC supply.
IV. Start-up
1. Make sure all wiring has been completed correctly, and that any doors with cut-out sensors on them
have been properly closed.
2. Turn on the indoor fan circuit breaker only, and run the fan to adjust its airflow to that
desired.
3. Now, ensure all circuit breakers have been turned on.
4. Turn power on and wait for the controller to boot up and complete a self test. The unit is ready
when the idle screen has been displayed.
5. Check for system faults. See sections on faults and trouble-shooting later in this document for
assistance.
6. Resolve fault issues, if any, making sure all fault messages have been cleared.
7. The system is now ready to run. Turn it on at the thermostat and ensure the compressor and fans
all start and run in the correct direction.
V. Splat LT2 Controller
General description
The LT2 controller is an advanced microprocessor based controller for two stage air conditioning units
utilizing 1 or 2 compressors per stage. It incorporates reverse acting head pressure (RAHP) control of
the outdoor fans, with separate outputs to control the star/delta operating mode of the outdoor fans.
This has resulted in a highly integrated design utilising fewer components, improving reliability.
Features include:
High performance FLASH memory
Built in continuous self checking ensures controller is running correctly and will reset
the system if an error is detected.
Low cost thermistor sensor inputs for defrost detection with short and open circuit fault
detection.
Built in user interface with back lit LCD and 4 on board push buttons allow the system
configuration to be changed and status information to be viewed.
Speed up button with indication LED.
On board 240 VAC 20 Amp rated relay for direct outdoor fan control when RAHP mode
is not used.
RAHP control of outdoor fan with interlocked and time sequenced star and delta relay
outputs.
On board fusing of thermostat and control gear 24 VAC power.
Four levels of heating/cooling possible due to the use of 2 compressors per stage and 4
stage calls provided at the thermostat connection terminals.
High speed RS485 expansion interface for connecting a wide range of auxiliary functions
to the controller (Xwire).
Optically isolated RS485 communications interface running protocols such as MODBUS
RTU for remote control/sensing via touch screen, computer and BMS systems.
PC application available (CommAir MODBUS Diagnostic Tool) allowing unit to be monitored
and controlled remotely.
Low power design.
Built in run hour counters for all compressors.
Non volatile fault logging allows up to the last 20 faults to be viewed. Fault history can
also be cleared.
Real time status display including faults, running status and readout of outdoor coil
temperature (when defrost sensors are fitted).
Safety interlock sensors/switches act directly by interrupting the 24 VAC power to the
various control outputs, regardless of the microprocessor control.
Fault relay output (low voltage dry contact).
Page 4 of 42
IM-HOA 2 ST Rev 2.0 - 21/07/2013

VI. LT2 CONTROLLER LAYOUT & FUNCTIONS
There are four buttons located below the LCD display screen which are: SPEED UP, SETUP, TRIP VIEW and
TRIP STEP.
a. SPEED UP:
Press and release the <SPEED UP> button quickly to turn on or turn off the speed up mode. The LED next
to it will light up if the speed up is active. The LED is off if the speed up is inactive. As a
failsafe, speed up mode will automatically turn off 1 hour after activation. The Speed Up is for
testing and trouble shooting, with normally functioning delays being decreased per the table below.
Speed up can only be toggled via the speed up button while the controller is displaying any one of
it’s idle screens. The table below outlines normal vs speed up times:
Normal time Speed Up Time Description
1 second 1 second Time to wait before reporting a new stable RAHP change
5 minutes 15 seconds Minimum ODF run time before a STAR/DELTA change is permitted
5 minutes 1 minute Compressor anti cycle time
10 seconds 10 seconds Defrost sensor must be continuously low for this period before
unit commit to defrost
30 minutes 70 seconds Minimum time delay between defrost cycles
10 minutes 2 minutes Maximum defrost run time
90 seconds 10 seconds Minimum compressor run time before activating defrost
5 minutes 5 seconds Low pressure relay override timer, LP bypassed time after
defrost
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Page 5 of 42
IM-HOA 2 ST Rev 2.0 - 21/07/2013

b. SETUP Menu:
The setup menu can only be activated from an idle screen (See dbelow). Once the setup menu is active,
the buttons possess the following functions:
- <SPEEDUP>: Scroll to previous menu item.
- <SETUP>: Scroll to next menu item.
- <TRIP VIEW>: Softkey – The text above the key explains the function.
- <TRIP STEP>: Softkey – The text above the key explains the function.
The setup menu will remain visible for 1 minute after the last button has been pressed. After this
time, the system will return to the idle screen and any changes made will be lost unless already
saved. The board provides an opportunity to save at completion of setup choices.
Press and hold the <SETUP> button until the
<Setup Menu> is displayed on the screen then
release it to enable scrolling through the
menu.
As soon as the <SETUP> button is released,
Stage 1 compressor 1 runtime hours is
displayed:
Press <TRIPSTEP> to clear this compressor's
runtime hour count (if needed).
Now press the <SETUP> button again. Stage 1
compressor 2 runtime hour is displayed:
Pressing the <SETUP> button again brings up
Stage 2 compressor 1 runtime, pressing <SETUP>
one more time brings up Stage 2 compressor 2.
Again, press <TRIPSTEP> to clear each
compressor's runtime hour count (if needed).
Now press the <SETUP> button again. The MODBUS
address is displayed:
This allows the MODBUS address to be set.
Press <TRIPVIEW> to increment the address, or
<TRIPSTEP> to decrement. Holding either button
will start automatic counting.
Pressing the <SETUP> button again gives a
choice of “Control source”. Possible
choices are either “thermostat” or
“MODBUS” control. Pressing the <TRIPSTEP>
button toggles between "Thermostat" or
"MODBUS" control. (Choosing Thermostat
control does not remove the ability to
display MODBUS available outputs.)
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Page 6 of 42
IM-HOA 2 ST Rev 2.0 - 21/07/2013

Press the <SETUP> button again. “HVAC
type” is displayed allowing the user to
choose between a “Cool Only” or “Heat
pump” (Reverse cycle) system.
Press <TRIP STEP> to toggle between “Cool
Only” or “Heat & Cool”.
Press the <SETUP> button again for “Comp
selection” screen. This allows the user
to choose a simple load balancing
behaviour, called lead/lag, if desired.
Press <TRIPSTEP> to toggle between
"Direct" and "Balanced". Direct allows
each compressor to be controlled directly
from the compressor call inputs. Balanced
allows the controller to toggle between
compressors used for each successive
compressor call input. It is provided to
help balance out the wear on all
compressors.
Press the <SETUP> button again for “Comp
paired run” window. This allows the
compressors to be run as a pair only with
a 10 second interval between lead and lag
compressor start, or as individual only.
If “paired” is chosen, connect thermostat
to st 1 connection on control board.
Press <TRIPSTEP> to toggle between
"Individual" and "Paired".
Pressing the <SETUP> button again selects
“Comp fault mode”. This feature provides
compressor fault pairing if desired.
Press <TRIPSTEP> to toggle between
"Paired" and "Individual". "Paired" means
any single compressor electrical fault
will shut down both compressors in the
tandem pair. "Individual" means a single
electrical fault only shuts down the
offending compressor. Note that with
tandem compressor arrangements, because
of common pipework between the
compressors in a tandem arrangement, an
HP or LP fault will automatically shut
down both compressors.
Press the <SETUP> button again. The “RAHP
sensor” window is displayed providing
control of Outdoor Fan speed. Press
<TRIPSTEP> to toggle between "Not Fitted"
and "Fitted". "Not Fitted" means the
Outdoor fan runs at one speed only.
"Fitted" means with RAHP inputs, the
Outdoor fan can operate with LOW or HIGH
speed based on the measured Outdoor coil
pressure during Cooling mode only. RAHP
will be ignored during Heating hence the
outdoor fan will be forced to run in HIGH
s
p
eed.
Now press the <SETUP> button again.
“Defrost sensor” is displayed which
allows the user to set the presence of a
defrost sensor.
If “Heat&Cool” has been selected in <HVAC
type> window above, the choice of defrost
sensor fitment is removed and the program
forced to "Fitted"(ie: heatpump systems
must have defrost sensors on the outdoor
coils). Otherwise for cooling only
systems, press <TRIPSTEP> to toggle
between "Fitted" and "Not Fitted". If set
to fitted for a cooling only system,
thermistor faults will be logged, but the
stage will not be shut down.
Further notes on “Comp paired run” above:
1. For single compressor installations, “Paired” or
“Individual” mode can be selected. Make sure the
1 stage thermostat is connected to St 1 output on
control board.
2. For tandem compressors, see separate window above
left for setu
p
choices.
Page 7 of 42
IM-HOA 2 ST Rev 2.0 - 21/07/2013

c. “Dash Board” Screens
Picture 1 Picture 2
Stage 1 run hours Stage 2 run hours
Press <SETUP> button again to give
access to “Current transfmr”. This
enables the user to set the presence of
a Current transformer (CT). The use of a
CT is purely for information. It does
not control anything in the system.
Press <TRIPSTEP> to toggle between "Not
Fitted" and "Fitted". "Not Fitted" means
the Current Transformer is not used.
"Fitted" means the Current Transformer
is used and connected to the LT1
controller for measuring the current
consumption of compressor(s).
Now press the <SETUP> button again. The “Save
changes?” is displayed which allows to save the
changed item(s), by selecting "Y" (pressing the
<TRIP VIEW> button) or abandoning the changes by
selecting "N" (pressing the <TRIP STEP> button)
and returning to the idle screen.
A collection of other readings are available on
the dashboard screen. The dashboard can only be
activated while one of the idle screens is
visible.
Press and hold the <TRIPSTEP> button to see the
dashboard. Each press and hold of <TRIPSTEP> will
display the next dashboard. Dashboards are
displayed in the following order:
- Defrost sensor temperature. This will
appear as picture 1 if the unit has sensors
fitted, good connection and LT1 controller
configured with “Defrost sensor [Fitted]“
or as picture 2 if the unit has sensors
fitted, bad connection (or faulty sensor)
and LT1 controller configured with “Defrost
sensor [Fitted]“ .
Compressor(s) runtime hours
Page 8 of 42
IM-HOA 2 ST Rev 2.0 - 21/07/2013

d. Idle Screen
When the controller is powered and no buttons are being pressed, the screen will read out the current
operating status of the controller. Typically the screen will look like this:
S1 C1 = xxx C2 = xxx
S2 C2 = xxx C2 = xxx
"S1" indicates the state of the compressors for stage 1 and “S2” for stage 2.
The marker "xxx" will be one of the following messages:
"Off" : The compressor is off and no calls are pending.
"O/L" : The compressor is currently in overload and has been shutdown.
"Flt" : The compressor had been in overload but isn't any longer. It is now waiting for the
call to be removed to reset the fault and permit it to run again.
"Icy" : The compressor is running in Cool mode.
"Hot" : The compressor is running in Heat mode.
"Tmr" : The compressor is now off and the anti-cycle timer is running.
"Rdy" : A compressor call is present and this compressor is scheduled to start once other
items, like the outdoor fan, have turned on.
"Ast" : The compressor is assisting with a defrost cycle. It is providing heat to
compensate for the other stage that is defrosting.
"Dfr" : The compressor is running in defrost mode to remove ice from the coil.
A fault that affects the whole stage will appear on the whole line for that stage. The following
errors are possible.
- "Low Pressure" : The refrigeration gas pressure is too low.
- "High Pressure" : The refrigeration gas pressure is too high.
- "ODF overload" : The Outdoor Fan is currently in overload, or the door of the outdoor fan
compartment is open, which has caused the Door safety switch to exhibit an open circuit. The outdoor
fan circuit breaker might also be turned off, or the Internal thermal protection of outdoor fan motor
is opened circuit and the motor has been switched off. No compressors for this stage are running.
- "Pending reset" : The Outdoor Fan had been in overload but isn't any longer, or the defrost sensor
was faulty and the fault has been corrected. It is now waiting for all the stage calls to be removed
to reset the fault and permit this stage to run again.
A fault that affects both stages will occupy the whole screen. If any of these errors occur, neither
stage will be able to run. The following errors are possible:
- "Mains Phase Fault" : The mains phase error input has triggered.
- "Indoor Fan Overload" : The indoor fan is in overload.
- "Indoor Fan Fault Reset IDF call" : The indoor fan had been in overload but isn't any longer. The
system is now waiting for the indoor fan call to clear to reset the fault and permit it to run again.
- "Mains Fuse Failure" : The fault chain fuse blown.
- "Thermostat Fuse Failure" : Thermostat fuse blown.
e. Fault History
The system saves the last 20 faults and retains this information even during power failure. The fault
history can only be activated whilst one of the idle screens are visible.
Press and hold the <TRIPVIEW> button to see the history. While keeping <TRIP VIEW> held, press and
release <TRIP STEP> to step through the history.
The following faults are able to be reported:
- "Main fuse " : Fault chain fuse blown
- "Phase failure " : Phase failure
- "Indoor fan O/L" : Indoor fan overload
- "S1 low press " : Stage 1 low pressure
- "S1 high press " : Stage 1 high pressure
- "S1 ODF O/L " : Stage 1 outdoor fan overload
- "S1 Comp 1 O/L " : Stage 1 compressor 1 overload
- "S1 Comp 2 O/L " : Stage 1 compressor 2 overload
- "S1 RAHP fault " : Stage 1 RAHP fault
- "Config chkfail" : Config checksum corruption
- "Hr mtr chkfail" : Hour meters checksum corruption
- "ErrLog chkfail" : Error log checksum corruption
- "ThermostatFuse" : Thermostat fuse blown
- "S2 low press " : Stage 2 low pressure
- "S2 high press " : Stage 2 high pressure
- "S2 ODF O/L " : Stage 2 outdoor fan overload
- "S2 Comp 1 O/L " : Stage 2 compressor 1 overload
- "S2 Comp 2 O/L " : Stage 2 compressor 2 overload
- "S2 RAHP fault " : Stage 2 RAHP fault
- "S1 defr sensor" : Stage 1 defrost sensor (shorted or open circuit wires)
- "S2 defr sensor" : Stage 2 defrost sensor (shorted or open circuit wires)
- "S1 CT CommsErr" : Stage 1 current transformer lost comms
- "S2 CT CommsErr" : Stage 2 current transformer lost comms
The fault history may be cleared while it is being viewed. To clear it, keep <TRIPVIEW> held and hold
<TRIPSTEP> for 6 seconds. The history will then be erased and cannot be recovered.
Please note that if faults "Config chkfail", "Hr mtr chkfail" and "ErrLog chkfail" occur in the field,
the board should be replaced.
Page 9 of 42
IM-HOA 2 ST Rev 2.0 - 21/07/2013

VII. Trouble shooting
Fault Code Displaying Symptom(s) Part(s) to check and How to correct the
fault(s)
S1 C1=Off C2=Off
S2 C1=Off C2=Off
The compressors and
Outdoor Fans are off.
Indoor fan is
running.
The compressors are off and no calls are
pending.
S1 C1=Tmr C2=Tmr
S2 C1=Tmr C2=Tmr
The compressors and
Outdoor Fans are off.
Indoor fan is
running.
The compressors are off and the anti-cycle
timers are running.
S1 C1=O/L C2=Off
S2 C1=Off C2=Off
The compressors and
Outdoor Fans are off.
Indoor fan is
running.
Compressor 1 Overload Relay of the stage 1 is
tripped. Reset it.
The compressor 2 of stage 1 and compressor 1 & 2
of stage 2 are off and no calls are pending for
those.
S1 C1=O/L C2=Tmr
S2 C1=Tmr C2=Tmr
The compressors and
Outdoor Fans are off.
Indoor fan is
running.
Compressor 1 Overload Relay of the stage 1 is
tripped. Reset it.
The compressor 2 of stage 1 and compressor 1 & 2
of stage 2 are off and the anti-cycle timers for
those are running.
S1 C1=Off C2=O/L
S2 C1=Off C2=Off
The compressors and
Outdoor Fans are off.
Indoor fan is
running.
Compressor 2 Overload Relay of the stage 1 is
tripped. Reset it.
The compressor 1 of stage 1 and compressor 1 & 2
of stage 2 are off and no calls are pending for
those.
S1 C1=Tmr C2=O/L
S2 C1=Tmr C2=Tmr
The compressors and
Outdoor Fans are off.
Indoor fan is
running.
Compressor 2 Overload Relay of the stage 1 is
tripped. Reset it.
The compressor 1 of stage 1 and compressor 1 & 2
of stage 2 are off and the anti-cycle timers for
those are running.
S1 C1=Flt C2=Off
S2 C1=Off C2=Off
The compressors and
Outdoor Fans are off.
Indoor fan is
running.
The compressor 1 of stage 1 has been in overload
but isn't any longer. It is now waiting for the
call to be removed to reset the fault and permit
it to run again.
S1 C1=Flt C2=Tmr
S2 C1=Tmr C2=Tmr
The compressors and
Outdoor Fans are off.
Indoor fan is
running.
The compressor 1 of stage 1 has been in overload
but isn't any longer. It is now waiting for the
call to be removed to reset the fault and permit
it to run again.
S1 C1=Off C2=Flt
S2 C1=Off C2=Off
The compressors and
Outdoor Fans are off.
Indoor fan running.
The compressor 2 of stage 1 has been in overload
but isn't any longer. It is now waiting for the
call to be removed to reset the fault and permit
it to run again.
S1 C1=Tmr C2=Flt
S2 C1=Tmr C2=Tmr
The compressors and
Outdoor Fans are off.
Indoor fan is
running.
The compressor 2 of stage 1 has been in overload
but isn't any longer. It is now waiting for the
call to be removed to reset the fault and permit
it to run again.
S1 C1=Off C2=Off
S2 C1=O/L C2=Off
The compressors and
Outdoor Fans are off.
Indoor fan is
running.
Compressor 1 Overload Relay of the stage 2 is
tripped. Reset it.
The compressor 1 & 2 of stage 1 and compressor 2
of stage 2 are off and no calls are pending for
those.
S1 C1=Tmr C2=Tmr
S2 C1=O/L C2=Tmr
The compressors and
Outdoor Fans are off.
Indoor fan is
running.
Compressor 1 Overload Relay of the stage 2 is
tripped. Reset it.
The compressor 1 & 2 of stage 1 and compressor 2
of stage 2 are off and the anti-cycle timers for
those are running.
S1 C1=Off C2=Off
S2 C1=Off C2=O/L
The compressors and
Outdoor Fans are off.
Indoor fan is
running.
Compressor 2 Overload Relay of the stage 2 is
tripped. Reset it.
The compressor 1 & 2 of stage 1 and compressor 1
of stage 2 are off and no calls are pending for
those.
S1 C1=Tmr C2=Tmr
S2 C1=Tmr C2=O/L
The compressors and
Outdoor Fans are off.
Indoor fan is
running.
Compressor 2 Overload Relay of the stage 1 is
tripped. Reset it.
The compressor 1 & 2 of stage 1 and compressor 1
of stage 2 are off and the anti-cycle timers for
those are running.
S1 C1=Off C2=Off
S2 C1=Flt C2=Off
The compressors and
Outdoor Fans are off.
Indoor fan is
running.
The compressor 1 of stage 2 has been in overload
but isn't any longer. It is now waiting for the
call to be removed to reset the fault and permit
it to run again.
S1 C1=Tmr C2=Tmr
S2 C1=Flt C2=Tmr
The compressors and
Outdoor Fans are off.
Indoor fan is
running.
The compressor 1 of stage 2 has been in overload
but isn't any longer. It is now waiting for the
call to be removed to reset the fault and permit
it to run again.
S1 C1=Off C2=Off The compressors and The compressor 2 of stage 2 has been in overload
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IM-HOA 2 ST Rev 2.0 - 21/07/2013