A.O. Smith HPI-40C1.0AT User manual

Heat Pump Water Heater
HPI-40/50C1.0AT
User Guide
HPI-40/50C1.0AE

About A. O. Smith
In 1936, A. O. Smith developed and patented the process of
glass-lined water heaters, pioneering the modern standard in
water heater design. Over the past years, A. O. Smith has gained
respect and support of homeowners, contractors, architects, and
specifying engineers in over 60 countries by providing innova-
tive, energy-saving products designed for years of trouble-free
service.
A. O. Smith Water Products Company, now the largest water heater
manufacturer in the world, continues the tradition of innovation and
becomes a global leader in water product industry.

CONTENTS
User Guide................................................................................................................................................................ 1
Physical Characteristics..........................................................................................................................................2
Specifications ...............................................................................................................................................2
Safety Features..............................................................................................................................................3
Compressor overheating discharge protection...................................................................................................3
Abnormal operation protection of the relay....................................................................................................... 3
Abnormal operation protection of electronic expansion valve..........................................................................3
High and low voltage protection........................................................................................................................3
Refrigerant leakage protection........................................................................................................................... 3
High water temperature protection ....................................................................................................................3
High Temperature Limit Protection Switch....................................................................................................... 3
Temperature and pressure relief valve............................................................................................................... 3
Product Features......................................................................................................................................................4
Energy-saving Heating ...................................................................................................................................... 4
MAX ..................................................................... ..........................................................................4
AES (adaptive energy-saving system)............................................................................................................... 4
Circulating pump ...............................................................................................................................................4
Power-off memory.............................................................................................................................................4
Intelligent defrosting..........................................................................................................................................4
Intelligent dormancy.......................................................................................................................................... 4
Wired remote controller.....................................................................................................................................4
Glass-lined special protective tank.................................................................................................................... 4
Anode rod protection......................................................................................................................................... 4
High Efficiency Energy-saving Insulation......................................................................................................... 4
Installation Instructions..........................................................................................................................................5
Tank installation.................................................................................................................................................5
Pipe connection..................................................................................................................................................5
Condensate Water Pipe Connection...................................................................................................................6
Control box connection...................................................................................................................................... 6
Water filling.......................................................................................................................................................6
Operation Instructions............................................................................................................................................7
Electronic Controller Operation.........................................................................................................................7
Temperature and pressure relief valve Inspection............................................................................................11
Maintenance Instructions .....................................................................................................................................11
Maintenance..................................................................................................................................................... 11
Troubleshooting .....................................................................................................................................................12
Wiring diagram......................................................................................................................................................13
Notice ........................................................................................................................................................14
Packing list.................................................................................................................................................14
................

1
User Guide
Please read this instruction carefully before installation and operation of the water heater and keep this
instruction well for further reference.
zOnly professional installers acknowledged by A.O.SMITH are permitted to install the heat pump water
heater. If the water heater is installed with self-prepared installation materials or by un-authorized
personnel, A.O.SMITH will not be responsible for all losses incurred thereby, including but not limited
to pipeline leakage, fall or improper installation that may affect normal operation and performance of
water heater.
zThe heat pump water heater is for residential application. Therefore, it may affect life expectation if it is
used for commercial application.
zAfter installation and operation of the heat pump water heater, users should inspect the system regularly
and make necessary maintenance according to operation conditions. If any abnormality occurs, please
stop operation immediately, and contact local authorized dealer for repair to ensure the normal, safe, and
reliable operation of the water heater.
zThe anode rod is a consumable part and it is generally suggested to check and replace the anode rod
every 2 or 3 years. Users could contact the local authorized dealer for check and replacement to extend
life expectation of water heater.
zPrior to any maintenance or repair of the heat pump water heater, please cut off power supply.
Unauthorized personnel are not permitted to adjust and repair the heater.
zIn case the water heater is subject to dry heating, the generated steam or burning water might lead to
serious scald. Therefore, it is necessary to fill the water heater with water. If dry heating occurs, cut off
the power and water supply at once, stop the operation, contact local authorized dealer, and carry out
inspection or repair by our company recommended professional installers.
zIn case of any component soaked by water, the water heater is not permitted to use until checked by
authorized service staff.
zMain components of the storage electrical heater are protected by insulation material to ensure safety use.
Any damaged power cords should be replaced by authorized service staff.
zThe pressure relief valve, equipped on the heat pump water heater, is forbidden to change installation
position or be blocked. Discharge pipe is required to connect the valve and down toward floor drain.
zWater, including hot water, out of the heat pump water heater is not permitted for drinking.
zElectricity for the heat pump water heater should be supplied by independent branch of circuit, of which
electricity meter, breaker, maximum current need to be checked by professional electrician in advance.
zPower socket should be located at a dry place, and power cord should not be pu shed or pulled with wet
hand to avoid the danger of electric shock.
zDamaged electric wire, aged, loose and unfixed socket are not suggested to be used because of the
danger of electric shock, short circuits, fires, etc. Please ensure power cord and socket could be
connected well.
zA. O. SMITH water Heater Company Ltd reserves the rights to explain all provisions mentioned above.
CAUTION: Failure to follow instructions in the user guide may cause fire disaster, which would be a threat
to life and property security.
WARNING: Heat pump water heater is not permitted for use without reliable ground wire circuit for power
socket. In case of indicator lighted up for “ground wire circuit fault”, please immediately stop
using, pull plug and contact local authorized dealer. Well-drained floor drain is essential to
prevent the damage to surroundings or downstairs in case of leakage of heater or joint.

2
Physical Characteristics
Figure 1 Physical Characteristics
Table 1 Outline Dimensions
Model HPI-40C1.0AT/AE
Total Height L (mm) 1610 1800
Height between Undersurface and Water Outlet L2 (mm) 1056 1243
Tank Diameter D (mm) ĭ520 ĭ520
Specifications
Table 2 Specifications
Model Rated
volume(L)
Voltage
(V)/
Frequency
(Hz)
Rated
input
power
(W)
Rated
current
(A)
Setting
temperature
range (°C)
Noise
level
dB(A)
Rated
pressure
(MPa)
Maximum
power of
quick
heating
(W)
Maximum
current of
quick
heating
(A)
Net
weight
(kg)
150 89
150 220~/50 3000 13.6 35-75 50 1.03 3000 13.6 98
Water outlet
Condensate
outlet
Relief
valve
Water inlet Base wad
(20 mm in
height)
Drain
valve
HPI-50C1.0AT/AE
HPI-40C1.0AT/AE
HPI-50C1.0AT/AE

3
Safety Feature
Compressor overheating discharge protection
The system will promptly stop the operation of the compressor to ensure safety in case the compressor
overheats due to the fault of the water heater.
Abnormal operation protection of the relay
The system will shut down all loads to prevent overvoltage, fire and other incident in case the water
temperature continues rising after the stop of pump due to the fault of the relay.
Abnormal operation protection of electronic expansion valve
The system will stop the operation of the compressor to protect the pump due to the electronic expansion
valve not working or not working properly.
High and low voltage protection
The system will promptly shut down all loads to protect the component and prevent the electric appliances
accidents due to the high or low voltage beyond the safety level.
Refrigerant leakage protection
The system will promptly stop the operation of the compressor protect the pump in case the leakage of the
refrigerant.
High water temperature protection
The system will shut down all loads to ensure safety in case any of the multiple sensors inside the water
heater reaches 90°C.
High Temperature Limit Protection Switch
A high temperature limit protection thermal cutout is equipped on the
heat pump water heater. The switch cuts off the phase and neutral line
instantaneously and simultaneously to guarantee safety in case water
temperature reaches the high temp limited due to water heater fault. If
this happens, please contact local authorized dealer.
Temperature and pressure relief valve
The water heater has a temperature and pressure relief valve, model
number: NPT3/4 1.03(see Figure 1), Default setting by factory is at
1.03MPa and not adjustable. The valve must be installed in the
position shown in Figure 1. The valve will release the pressure
automatically when the pressure in the water heater exceeds 1.03MPa or the temperature exceeds 99°C..
Figure2
Temperature and pressure relief
Relief valve
Drain valve
This valve must install with a drain pipe at its outlet, and the pipe should be installed downward in a
frost-free environment, the diversion pipe overflow water should be discharged to floor drain.

4
Product Features
Energy-saving Heating
A new generation water heater, heating residential water by air-source
based on the Inverse Cano Principle.
MAX
MAX function means more hot water output, therefore, better bath
experience.
AES (adaptive energy-saving system)
By recording and learning user’s habit of water usage, patented AES
feature adopts heating cycles automatically, which will facilitate water
usage and save energy by minimizing thermal loss.
Hot Water Amount Display
Five light blocks visibly indicate the hot water amount available in tank.
Circulating pump
The cold water section can be removed by pump circulation (sold separately) to ensure hot water at all time.
Power-off memory
By power-on more than 4 hours, the water heater could keep setting information for 72 hours when power
supply is cut-off.
Intelligent defrosting
The automatic intelligent defrost function can solve the problems effectively such as freezing of exchanger,
frost remaining etc., and ensure the system to be operated efficiently and stably.
Intelligent dormancy
If no operation is performed within 3 minutes, the water heater enters into a dormant state.
The unit will enter sleep state with no operation within three minutes.
Wired remote controller
The controller and the unit are to be installed separately for clear sight and convenient operation.
Glass-lined special protective tank
The Glass-lined protection tank is a patent by A.O.Smith, coating tank with Silicide smoothly and fusion at
870 . The anti℃-rust and anti-scaling glass coating has pass 100,000 cycles fatigue life test in accordance
with relevant UL Standards.
Anode rod protection
A powerful steel-core-anode rod is used to protect tank and greatly prolong service life of the heat pump
water heater.
High Efficiency Energy-saving Insulation
A polyurethane foam insulating layer without Freon reduces heat loss effectively.
Figure 3
EFFICIENCY
1 2
SETTING
PROGRAM
INSTANT
MODE PUMP
HYBRIDTURBO
PUMP

5
Installation Instructions
CAUTION:
z2 or more staffs are needed to move or install the heat pump water heater due to the heavy weight.
zThe water heater can be suitable for outdoor installation. In this situation, firm fixed measures for the
water heater are required. The water heater has the risk of falling down and seriously injuring without a
confirmation of the reliability before operation.
zTo climb on the tank or outdoor unit of the water heater is prohibited, which has the risk of serious
personnel injury accident.
zDo not touch the aluminum sheet on the air inlet side of the outdoor unit of the water heater, or there is a
risk of cut.
zThe maximum power of the water heater is 3000W. It’s recommended to use separate circuit with the
wire diameter no less than 2.5mm2.
zEnsure the water heater to stand still for at least 30 minutes after the unit is loaded, and then connect it
to the power supply.
Tank installation
zMake sure the floor where the tank is placed can bear approximately 1.5 times weight of the tank when
it is fully filled with water. During the installation, the tank cannot touch the floor directly, and there
should be a raised bottom at around 20mm under the tank. Please make sure the tank is loaded steadily.
zThe tank of the water heater shall be installed near to the power socket, sewer mouth and the area where
water is needed (Figure 4).
zBecause high temperature water may drain from the temperature and pressure relief valve on the tank
during the usage of the water heater, the drainage pipes of the pressure relief port must be connected to
floor drain to prevent scald.
zThe water heater should be located in an area where leakage of the water heater or the pipe joint will not
damage to the subjects around or the lower floors of the building.
Pipe connection
Please install the inlet and outlet pipe with the instruction on the according
points on the water heater. The check valve in the accessories must be
installed at the water inlet pipe. If the water pressure of the water inlet pipe
is near to or exceeds the release value of relief valve (1.03MPa), please
install a pressure reducing valve in the water inlet pipe far from the water
heater (Figure 5).
CAUTION: Teflon tapes or sealing rings shall be used at the pipe joints to
prevent leakage. Meanwhile, the relief valve cannot be too tight to prevent
damage.
Figure 4
Installation diagram of tank
Condensate
Water Pipe

6
Condensate Water Pipe Connection
Ensure the condensate water pipe, connected with condensate water outlet, is unobstructed and toward floor
drain without bended. (Figure 4)
Control box connection
When installing the control box on the wall, if the threading groove or wire
clamper is installed on the surface, please put the control wire directly into the
threading groove or wire clamper and then set the control box on the fixed
plate (standard configuration) which is preinstalled on the wall. If the
threading groove is pre-buried in the wall, firstly open the cover of the control
box then remove the 4 screws from the control box. And open the control box
and tale out the control wire from it, pulling out it from the display board.
And then let the control wire pass through the wire pipe (please note not to
damage the two-core plug and the wire), inserting the two-core plug on the
display board. Next send the display board back to the control box and close
the lid of control box with tightened screw. Finally fix the whole control box
on the 86 box which is preinstalled on the wall.
Power Connection
zAll the wires must come with water heater and be installed or replaced by authorized dealer, instead of
being installed by user’s own.
zIt must be reliable grounded as showed in Figure 6 to avoid electric shocking. Make the ground wire
connect the longer wire core than others and be the final one to be tightened under external force.
zEnsure the wires be fixed well with the plates after finish connecting.
Water Filling
After all the pipes connection, open the outlet valve of the heater and then the
inlet valve. Fill heater tank with water until water flowing smoothly through
outlet pipe, which means the tank is full of water. Shut off the outlet valve,
and check if there is any leakage at joints. If yes, evacuate the tank, fix joints
and repeat until no leakage appears.
Figure 5
Installation diagram of
check valve
Figure 6
check valve water inlet pipe
Water pipe nipple
Pressing line
plate for the unit
Indoor/outdoor unit
communication
Power supply wiring diagram
Terminal strip of
outdoor unit
Ground
3-wired cable

7
Operation Instructions
NOTICE: Please make sure the water has been fully filled into the tank and power cord is well connected.
Then make sure the water heater stand still for at least 30 minutes before powering up.
Electronic Controller Operation
1. Initial Power On
For the first-ever power connection.electronic
controller will run self-inspection program. All
indicators on the screen will light up and last for a
few minutes and then power-off. ( Figure 7)
Note
If the water heater is powered off (power outage or
power supply disconnected), when the water heater is
recycled, the temperature, timer, AES, operating
mode settings will return to the states before power
off.
2. Power On/Off
Press Power ON/OFF button, the heater will
be power-on. Setting temp and actual temp will be
displayed a few seconds later. ( Figure 8)
When heater is power on, pressing Power ON/OFF
button turn the heater into power-off status.
Default settings: Temperature at 65℃, Clock at
12:00.
Figure 7
Figure 8
3. Temperature setting
With the power on, press “ ” or “ ” to increase or decrease the set temperature by 1℃. Press and hold
the buttons to change the set temperature continuously and release to stop changing. The temperature range
is 35℃-75℃.
4.Timing
Prior to timing, clock should be set to the standard time. With the power on, Press “
” button to display
the clock, and then press it repeatedly to display “TIMER 1”, “TIMER 2” “TIMER 1+TIMER 2” in a
sequence.
Power Switch
Increase
Hot Water Amount Display
Decrease
AES Function
Heating Indicator
EFFICIENCY
1
2
SETTING
PROGRAM
INSTANT
MODE PUMP
HYBRIDTURBO
PUMP
SETTING
PROGRAM
INSTANT
MODE PUMP
PROGRA
“”

8
Clock setting
Long press the key“ ” to enter clock setting state
under non-timing state, the hour digit will flash;
press the key “ ” or “ ”to set the hour with a range
of “0-23”, then press the key “ ”, the minute digit
will flash; press the key “ ” or “ ”to set the minute
with a range of “0-59”. If the key is hold, the data
will change consecutively, then press the key“ ”,
the clock setting will be completed and exit the clock
setting state.
Figure 9
Clock view:
Under the startup state, press the key “ ” once to
display the time (Figure 9) for 16 seconds and then to
return to original state.
Long press the key“ ” to enter clock setting state under non-timing state, the hour digit will flash; press
the key “ ” or “ ”to set the hour with a range of “0-23”, then press the key “ ”, the minute digit will
flash; press the key “ ” or “ ”to set the minute with a range of “0-59”. If the key is hold, the data will
change consecutively, then press the key“ ”, the clock setting will be completed and exit the clock
setting state.
Clock view: under the startup state, press the key “ ” once to display the time (Figure 9) for 16 seconds
and then to return to original state.
Timer Setting
With the indicator TIMER 1 lighted up, long press and hold “ ” button to enter TIMER1 starting time
setting state. “TIMER 1” “ON”, hour and minute digits will flash at the same time. Press “ ” or “ ” to
increase or decrease the hour by 1 and the minute by 30.If the key “ ” or “ ” is hold, the set digit will
change consecutively. After finishing the start time setting, press “ ”button to enter TIMER 1 ending
time setting state. “TIMER 1” “OFF”, hour and minute digits will flash at the same time. The stop time
setting is same as above. Press“ ” button to confirm the “TIMER 1” setting. (Figure 10, 11)
When the indicator light “TIMER 2” is on: the setting method is same as above.
With indicator of both Timer-1 and Timer-2 light up, water heater will work in both periods.
Figure 10 Figure 11 Figure 12
PROGRAM
INSTANT
MODE PUMP
1
PROGRAM
INSTANT
MODE PUMP
1
PROGRAM
INSTANT
MODE PUMP
SETTING
PROGRAM
INSTANT
MODE PUMP
PROGRA
PROGRA
PROGRA
PROGRA
PROGRA
PROGRA
PROGRA
PROGRA
PROGRA
PROGRA
PROGRA
The heating timer interval can be set based on the personal water consumption need, i.e. the point to start or
stop of the water heater.

9
NOTICE:
1. “TIMER 1” default timer interval: 21:00-08:00;
2. “TIMER 2” default timer interval: 08:00-13:00;
4.AES
Press“ ”button to display and enter AES mode. Press“ ”button again to exit from AES
working mode. (Figure 12)
Note: AES could not work simultaneously with any timer, which means once AES turns on, Timer will turn
off automatically.
5. Instant heating
Figure 13
Figure 14
SETTING
PROGRAM
INSTANT
MODE PUMP
SETTING
PROGRAM
INSTANT
MODE PUMP
Neither TIMER 1 nor TIMER 2 could work simultaneously with AES, that means once TIMER 1 or
TIMER 2 turns on, AES will turn off automatically.
Press “ ”to turn on “ Instant heating ” with flashes for three times, both electric heater and pump heater
are operating at same time ( Figure 12, 13), the circulating pump is operating single time at same time, the
electric heater will be activated in case the pump heater is not under operation condition. Press again to
turn off “Instant heating” with flashes for three times.
INSTANT
INSTANT
“ ”

10
6. Pump circulation (Figure 15)
Press the key “ ”, and then the character “Pump” will be lighted on and the pump installed in the inlet
and outlet pipes of the water heater will start the circulation immediately.
Timing setting of circulation pump
Long press the key “ ” to enter the setting of
the circulation pump, and press the key “ ” or “ ”
to adjust the temperature. Then press the key “ ”
to enter the setting of the starting and ending time of
the circulation pump. Detailed timing setting
operation please refers to the timing setting.
The default set temperature of the circulation pump
is 45°C; the adjustable range of the temperature is
40°C-65°C.
The default operation period of the circulation pumps
respectively are 06:00-09:00 and 17:00-22:00.
Figure 15
7. Reset
Reset may help heater recover from misoperation or fault. Press and hold both “PROGRAM” and
“INSTANT” simultaneously for 8 seconds, will turn off the heater after 2 seconds display off all characters
on screen, and reset setting temp, clock, timer to default status and remove AES memory and faulty code.
8.Heating mode
Press the key “
” to switch the heating mode between “EFFIENCY” and “HYBIRD TURBO” with the
lighted up indicator.
In Efficiency mode, the heater is heating highly efficiently;
In Hybrid Turbo mode, the heater is heating rapidly.
Temperature and pressure relief valve Inspection
Temperature and pressure relief valve is a kind of protection device against overpressure, thus it is a normal
phenomenon to see water discharged from safety valve when water pressure rises over 0.8Mpa due to
heating or supply reason. User should check temperature and pressure relief valve regularly as follow: open
handle on temperature and pressure relief valve to get rid of the calcium carbonate deposit and etc., if water
dose not discharge from valve, please contact local authorized dealer.
SETTING
PROGRAM
INSTANT
MODE PUMP
PUMP
PUMPP
PUMPP
MODE
”
PROGRA

11
Maintenance Instructions
Only authorized service staff is permitted formaintenance service. Improper maintenance
may have risk of serious injury or property damage.
WARNING: Ensure heater is disconnected from power source before maintenance to avoid electric shock.
CAUTION: User may do some easy repair works referring to the trouble shooting chart, before contact
local authorized dealer.
Maintenance
zDrain the tank if needed: Close water inlet valve, open drain valve, rotate the handle on the temperature
and pressure relive valve then drain water through discharge pipe.
zClean the tank regularly.
1. Cut off the power and empty the tank
2. Connect the water outlet pipe with tap water and fill water through this end. Open the drain valve to
connect with floor drain, and discharge water through this end.
3. Open water inlet valve to get maximum tap water flow, flush the tank until clean water come out of
tank.
4. Close the drain valve and reconnect the pipe joint, and check if there is leakage.
DECLARATION:
Be cautions in the hot water discharged from the tank, as it is at the risk of scald.
CAUTION:

12
Troubleshooting
Fault phenomenon Possible reasons Solution
No display
No hot water Water heater power off No power available in electric socket
Failure in control circuit or internal wiring
Power on water heater
Check electric socket
Contact local authorized dealer.
No display
Too high water
temperature
ECO error
Power board error Contact local authorized dealer
Display
No hot water Heating element or internal wiring failure Contact local authorized dealer
Water leakage Pipe connection lose
Tank leakage Contact local authorized dealer
Display “E1” White wiring with eight-core terminal short
circuit or open circuit Contact local authorized dealer
Display “E2” Blue wiring with eight-core terminal short
circuit or open circuit Contact local authorized dealer
Display “E4” Black wiring with eight-core terminal Short
circuit or open circuit Contact local authorized dealer
Display “E6” Red wiring with eight-core terminal short
circuit or open circuit Contact local authorized dealer
Display “E8” Abnormal anode bar wiring Contact local authorized dealer
Display “H6” Green wiring with eight-core terminal short
circuit or open circuit Contact local authorized dealer
Display “H7” Blue wiring with eight-core terminal short
circuit or open circuit Contact local authorized dealer
Display “H8” Yellow wiring with eight-core terminal short
circuit or open circuit Contact local authorized dealer
Display “H9” Black wiring with eight-core terminal Short
circuit or open circuit Contact local authorized dealer
Display “H0” The circulation pump temperature probe is
shorted or opened when the circulation pump
is started.
Contact local authorized dealer
Abnormal noise The inner components, brackets or pipe
deformation.
Screw is loosing
Contact local authorized dealer
Abnormal noise during
operation The normal noise during operation including: Fan operation
Compressor operation
Refrigerant flowing
Action of relay.
Contact local authorized dealer

13
Wiring diagram
Figure 16 Electrical wiring diagram
1
/3(
1

14
Notice
zBefore installation, check and confirm if water heater power, electricity meter and wiring match up with
each other.
zThe heat pump water heater should be grounded reliably. It is prohibited to connect the earth wire to
neutral wire or tap water pipe.
zWater of 50℃or above may have risk of scald. Please check water temp by hand and use water mixing
valve to get water in appropriate temperature.
zBe cautious about the hot water discharge through temperature and pressure safty valve, as it may have
risk to cause scald.
zFor indoor installation, it is normal that the air outlet grill may have a little condensate water if the
indoor environment temperature and humidity is at a higher level.
zThe display panel needs to be installed indoors, and waterproof measures must be taken if installed
outdoors.
Packing list
ITEM DESCRIPITION QTY
1 Tank of water heater 1
2 Fixed plate of controller 1
3 Screw 2
4 Silicon rubber sealing ring 4
5 Drain pipe 1
6 Water pipe nipple 2
7 Temperature and pressure relief
valve 1
8 Check valve 1
9 Drain valve 1
10 Manual 1

A.O.SMITH WATER HEATER CO., LTD
A.O.Smith reserves the right to make product changes or improvements at any time without notice. 500444-022 Rev. 00