Haier HWE24VCN User manual

Model No.
HWE24VCN
SERVICE MANUAL
Order No.AC0812S001V1
Group
Feature
Top Discharge Airflow Pattern
Modern Family-look Design
3 Cool Settings, 3 Fan Settings
Slide Out chassis
Easy-Access Washable Filter
Digital Time & Temperature Display
24 Hour on/off Timer
©2014 (Qingdao Haier Air Conditioner General corp.,Ltd)
All right reserved .Unauthorized copying and distribution is a violation of law
This service information is designed for experienced repair technicians only and is not designed for use by the general public.
It does not contain warnings or cautions to advise non-technical individuals of potential dangers in attempting to service a product.
Products powered by electricity should be serviced or repaired only by experienced professional technicians. Any attempt to service or
repair the product or products dealt with in this service information by anyone else could result in serious injury or death
WARNING
ON/OFF
MODE
SPEED
TIMER
TEMP/TIME
TEMP/TIME

1. Product Code Illumination and Series introduction.......................................
2. Specifications....................................................................................................
3. Safety and Precaution.......................................................................................4
4. Warning and Cautions.......................................................................................5
5. Installation and Accessory Parts......................................................................
7
6. Parts and Functions.........................................................................................
13
7. Abnormity Diagnose.........................................................................................
17
8. System Flow Chart...........................................................................................19
9. Circuit Diagram.................................................................................................21
10. Wiring Diagram...............................................................................................22
Table of Contents
2
3
HWE24VCN Table of Contents
Domestic Air Conditioner
1

HWE24VCN
24000/23500
230/208/60Hz
HWE24VCN

2.Specification
Item Unit HWE24VCN
Cooling capacity BTU/h 24000/23500
Heating capacity BTU/h /
Power supply 1PH/230/208/60HZ
Power input W 2550/2500
Running current A 11.1/12.1
Cooling
EER BTU/(h·W) 9.4/9.4
Power input W /
Running current A /
Heating
COP BTU/(h·W) /
Indoor side dB(A) 58
Sound Level Outdoor side dB(A) 63
18 21/32
26 9/16
24 13/32
22 3/8
29 13/16
29
Height inches
Width inches
Net dimensions
Depth inches
Height inches
Width inches
Packaging
dimensions Depth inches
Net lbs
lbs
Weight Gross
Type Rotary
Model / ASH232SN-C8DU1
Compressor
Running cap. For comp. µF 50
Hi-Pressure Psig 560
Pressure Low-Pressure Psig 270
Model R22 or
R410A R410A
Refrigerant
Charge OZ 34.2
Indoor unit / centrifugal
Type Outdoor unit / axial
Fan
Fan Speed Indoor unit r/min
Air volume CFM
Moisture removal Pints/hr
129.2
143.5
HWE24VCN Specification
Domestic Air Conditioner
2
1120/1060/980
540/510/470
7.8

HWE24VCN Safety and Precaution
Domestic Air Conditioner
4
3. Safety and Precaution
WARNING: Following these basic precautions will reduce the risk of fire ,electrical shock ,injury or death
when using your air conditioner .
1) Air conditioner must be connected to proper electrical outlet with the correct electrical supply .
4)DO NOT USE AN ADAPTER OR AN EXTENSION CORD.
5)When installing your air conditioner in a window,make sure the window is strong enough to hold the weight
of the air conditioner.You also want to secure and correctly install your air conditioner property to prevent it
from falling.Extra brackets or support may be required depending on your window.
3) DO not use if power cord is frayed or damage . Also avoid using if there are cracks or abrasion damage
along the length ,plug or connector .
6) Do not black airflow inside or outside the air conditioner with blinds,drapes,protective covers,shrubs or
bushes.
9)Always unplug the air conditioner before servicing it or moving it .
7)Be careful of sharp edges on the front and rear fins of the unit that could cut and cause serious injury.
8)Be careful when lifting the air conditioner to install or remove the unit . Always use two or more people
for this .
2) Proper grounding must be ensured to reduce the risk of shock and fire .
DO NOT CUT OR REMOVE THE GROUNDING PRONG.
If you do not have a three-prong electric receptacle outlet in the wall, have a certified electrician install the
proper receptacle . The wall receptacle MUST be properly grounded .

HWE24VCN Warning and Cautions
Domestic Air Conditioner
5
4.Warning and Cautions
WARNINGS: Following the safety messages is very important.
These messages can save you from being injured or killed. Warning symbols alert you to be
This room air conditioner must be grounded. Grounding reduces the risk of electric shock by
providing an escape wire for the electric current. The power cord has a grounding wire with a
grounding plug . Plug it into an outlet that is properly installed and grounded.
Improper use of the grounding plug can result in a risk of electric shock.
Call a qualified electrician if you don’t understand the grounding instructions or if you are not sure
if the air conditioner is properly grounded. If the wall outlet is not grounded, please contact an
electrician to have it replaced with a proper grounded outlet.
We strongly advise against using an adapter plug.
careful and means Danger . Always follow instructions to be safe and reduce chances of injury
or death . Warning and Danger signs will precede safety messages.
Electrical Safety
GROUNDING:
WARNING:
Do not, under any circumstances, cut or remove the third (ground) prong from the
power cord.
Adapter Plug:

HWE24VCN Warning and Cautions
Domestic Air Conditioner
6
TIPS
This air conditioner is designed for use in a double hung window.
When installing your air conditioner, make sure to seal all areas where there is a possibility of air leakage.
The airflow should not be blocked either inside by curtains, drapes or furniture, or outside bu shrubs or bushes.
Do not needlessly use electrical light or other appliances that produce heat.
Keep the blinds and drapes drawn on all other windows.
While cooking, use an exhaust fan in the kitchen to remove the excess heat.
Always use the correct BTU size air conditioner to cool the room to attain optimum efficiency.
While installing unit be sure to tilt air conditioner 5 degrees outward to have the water drip outside the house.
Install the unit on the north side, as that is normal the shaded side. This will enhance the operation of your unit.
Energy Saving Guide
The window has to be strong for installation. Extra brackets and/or support may be reqired depending on your
window. (Brachets and supports not included in all models.)
Masure the window before installing. If the window is too big for the unit, you may require professional installation.
Use the correct electric voltage and proper ampere for the unit to run effectively.
Only let a certified electrician modify your electrical outlet.
Use a dedicated line fot the operation of your air conditioner to avoid the possibility of an electrical surge.

HWE24VCN Installation and Accessory Parts
Domestic Air Conditioner
7
5. Installation and Accessory Parts
Check the following before you install your air conditioner:
1) The unit is free of all obstructions inside and outside the room e.g. drapes, curtains, furniture, plants,
shrubs, bushes, trees, other structures like building, garage etc.
Air conditioner must have clear unobstructed airflow through the condenser to remove the heat.
2) The window is strong enough to hold the weight of the air conditioner. Extra brackets or supports may be
needed depending on your windows. Brackets or supports not not provided in all models.
3) The window sill and track are strong enough to hold the weight of the air conditioner.
4) The wall is strong enough to hold the unit. Extra brackets or supports may be needed depending on the
wall. (Brackets or Supports not provided in all models).
5) There is adequate and proper power supply near the air conditioner.
6) DO NOT use adopter plugs.
7) DO NOT use extension cords.
8) DO NOT cut or remove the ground prong.
9) DO NOT modify the plug or the electrical wall outlet in any way. If plug does not fit the electrical outlet
have a certified electrician do the necessary change.
10) NOT connect electrical power to the unit before installation.
11) DO NOT use if power cord is worn out, hayed or damage. Avoid using if here are cracks or abrasion
damage along the length, plug or connection.
12) DO NOT install into any existing cabinet or sleeve which does not have ride and top air vents.
13) Be careful of exposed sharp edges of the cabinet and sharp coils (fins) on the back of the unit that could
cut and cause serious injury.

HWE24VCN Installation and Accessory Parts
Domestic Air Conditioner
8
A. 31 1⁄4” (79.4 cm) minimum
B. 20 1/4” (51.4 cm) minimum
Window Installation
Window opening measurements:
■31 1/4” minimum to 40” (79.4 cm to 101.6 cm) maximum opening
width.
■20 1/4 ” (51.4cm) minimum opening height.
A
B
.
Prepare unit for installation
PrepareAir Conditioner for Installation
CAUTION:
Never expose plastic front or grille to extreme temperatures.
1. ehtetarapeS.esuretalrofswercsesehtpeeK.)A(swercstnemhcattatnorfowtehtevomeR
cabinet from the front panel.
2. ehtgnisU.tenibacretuoehtfomottobehttadnuof)B(edisrepswercsowtehtevomeR
basepan handle, slowly and evenly pull out the chassis from the cabinet. Use two or more
people to move the air conditioner.
Unpack unit in the floor near the installation location
CAUTION: Never expose plastic front or grille to extreme temperatures.
1. Install the top channel with four (4) 7/16” self-tapping screws.
2. -thgirroftaepeR.slennahcmottobdnapotfoedistfelotniylbmessaniatrucdnah-tfeledilS
hand curtain assembly.
3. gnippat-fles”61/7)6(thgiehtiwtenibacehtfosedisehtotspirtsreniaterniatrucnetsaF
screws. (3) Self tapping screws on each side.
Assemble and install side curtains and top channel

HWE24VCN Installation and Accessory Parts
Domestic Air Conditioner
9
Prepare Window for Installation
1. Measure the width of the window opening.
2. Mark the center line on the inside windowsillwith a pencil.
NOTES:
Front
7/16" Self Tapping Screws
Top Channel
7/16" Self
Tapping Screws
Side Curtains
Fig. 1
Fig. 2
7/16" Self
Tapping Screws
Top Channel
WIDTH
WIDTH OF
WINDOW OPENING
CENTER
CENTER LINE
• Be sure your air conditioner does not fall out of the opening during installation or removal.
A grounded electrical outlet must be within 4 ft. (122 cm) of where the power supply cord
exits the air conditioner.
• Do not block the air discharge or air intake areas on the front panel.
• Do not block the louvers on the outside of the air conditioner.

HWE24VCN Installation and Accessory Parts
Domestic Air Conditioner
10
INSTALL THE CABINET IN THE WINDOW
1. htiwlliswodniwehtnognitsersititahtostenibacehtecalpoterusekaM.lliswodniwehtnitenibacehtretneC
a ¼" to ½" downward tilt towards the outside. Lower the window sash behind the front flange of the top channel
to hold the unit in place. The bottom channel must rest behind the window sill.
NOTE: The appearance of your model may differ from the one shown.
Bottom Channel
Window Sill
2. Expand both curtains so they contact the side window frame. Install four (4) 1” wood screws, two (2) in the upper
corners of the curtains and two (2) in the lower corners of the curtain.
3. s in the top mounting channel.wercsdoow”1)3(eerhtesU
4. Use two (2) 1" wood screws to fix the case to window sash.
5. Install 2-1/2” leveling bolts to the left and right brackets. Secure cabinet to left and right brackets using six (6)
7/16” self-tapping screws. 3 on each side.
6. Adjust two (2)-1/2" leveling bolts to proper length and use nut lock to secure bolt. Use a wood block between the
leveling bolts and the wall if required.
Top Channel
1" Wood
Screws
Window Sash
2-1/2 Bolt and
Nut Lock
Wood Block
7/16" Self
Tapping Screws

Domestic Air Conditioner
11
3. Place the window lock bracket as shown. Use one(1)1⁄8 ” drill bit to drill a starter hole through the hole in the
window lock bracket and into the upper window sash.
4. Attach the window lock bracket to the upper window with one (1) 1” wood screw to secure the window in place.
1. Uncoil the included foam seal.
COMPLETE THE INSTALLATION
INSTALLING THE CHASSIS TO THE CABINET
When moving or lifting the air conditioner chassis, use two or more people. Wear gloves when handling the air
conditioner to protect against possible sharp edges and metal fins.
1. Pick up the chassis carefully and evenly.
2. Slide the chassis into the cabinet.
3. Reinstall the front panel.
4. )A(.noitallatsniehtfotratsehttadevomerswercsehtgnisusissahcehtotlenaptnorfehteruceS
5. )B(.noitallatsniehtfotratsehttatenibacehtmorfdevomerswercsehtfoowtllatsnieR
HWE24VCN Installation and Accessory Parts
A
B
2. Insert the foam seal behind the top of the lower window sash and against the glass of the upper window.
A. Top of lower window sash
B. Foam seal
6. ".stnemeriuqeRlacirtcelE“eeS.noemoclliwthgilneergA.drocylppusrewopehtnoTESERsserP
A
B

HWE24VCN Installation and Accessory Parts
Domestic Air Conditioner
12
Parts
Tools
ON/OFF
MODE
SPEED
TIMER
TEMP/TIME
TEMP/TIME
Top channel Foam seal
Window lock bracket 7/16" self tapping
screws(10)
1" wood screws(10)
Side curtain frames(2) Remote control
Installation
brackets
7/16" bracket
screws(6) 2-1/2" bolt and
lock nut
Phillips head screwdriver
Flat-blade screwdriver
Scissors
Level
Socket wrench & sockets
Tape measure
Cordless drill and 1/8” bit
Pencil
Pliers
Adjustable wrench
Read and follow the instructions provided with any tools listed here.

6. Parts and Functions
HWE24VCN Parts and Functions
Domestic Air Conditioner
13
1. Press mode until you see the indicator light come on next to the desired setting.
2. Choose Fan, Cool, Energy Save or Dehum.
■Fan—Only the fan runs. Press SPEED to select High, Med or Low fan speed. The display shows the current
room temperature.
MODE
■Energy Save—In this mode the fan runs only when cooling is needed. The fan will run for 3 minute after the
compressor shuts off. The fan then cycles on for 1 or 2 minutes at 10 minute intervals until
the temperature in the room is above the set temperature. The compressor then turns back on.
■Dehum—Aids in removing humidity from the room. This setting will NOT cool the room.
1. Press FAN SPEED until; you see the indicator light come on next to the desired setting.
2. Choose High, Med, Low or Auto Cool
■High—For maximum cooling
■Med—For normal cooling
■Low—For minimum cooling
SPEED
FAN
DEHUM
ENERGY
SAVE
HIGH
MED
AUTO COOL
LOW
ON
OFF
SLEEP
MODE SPEED TIMER
°F/°C
Hr
TEMP/TIME
CLEAN
POWER
AUTO RESTART
FILTER
RESET
FILTER
MODE
SPEED
TIMER
FILTER RESET
TEMPERATURE / TIME
CLEAN FILTER INDICATOR
POWER
Auto Cool—Adjusts the fan speed automatically to provide ideal cooling based on the room temperature.
■
TIMER
To set the air conditioner to turn off between 1 hour and 24 hours (The air conditioner must be ON to set):
1. riaehterofebsruohgniniamerehtwohslliwyalpsidehT.hsalflliwthgilrotacidniffOremiT.REMITsserP
conditioner will turn off.
2. .sruoh42otruoh1morfemityaledehtegnahcotnottubworranwodropuEMIT/PMETehtsserP
3. roFFOremiTotemittfelehtwohslliwyalpsidehT.noniamerlliwthgilrotacidniffOremiT,sdnoces5retfA
the current temperature.
To set the Timer to turn on the air conditioner, keeping the previous settings:
1. Turn on the unit.
2. riaehterofebsruohgniniamerehtwohslliwyalpsidehT.hsalflliwthgilrotacidninOremiT.REMITsserP
conditioner will turn on.
3. .sruoh42otruoh1morfemityaledehtegnahcotnottubworranwodropuEMIT/PMETehtsserP
4. Timer On indicator light will remain on.
COOL
■Cool—Cools the room. Press SPEED to select High, Med , Low or Auto Cool speed. Press the TEMP/TIME
up or down arrow button to adjust the temperature.

HWE24VCN Parts and Functions
Domestic Air Conditioner
14
TO SET THE TIMER TO TURN ON THE AC, AND CHANGE THE PREVIOUS SETTINGS:
1. Turn on the air conditioner.
2. Adjust the mode to Fan, Cool, Energy Save or Dehum.
3. ehttsujda,edomevaSygrenErolooCroF.woLrodeM,hgiHotdeepsnafehttsujda,edommuheDronaFroF
fan speed to High, Med, Low or Auto Cool.
4. Adjust the temperature between 61°F and 86°F (16°C and 30°C).
NOTE: In Fan mode, the temperature cannot be set.
5. riaehterofebsruohgniniamerehtwohslliwyalpsidehT.hsalflliwthgilrotacidninOremiT.REMITsserP
conditioner will turn on.
6. .sruoh42otruoh1morfemityaledehtegnahcotnottubworranwodropuEMIT/PMETehtsserP
7. Timer On indicator light will remain on.
TO CLEAR TIMER PROGRAM:
NOTE: Air conditioner can be either on or off.
Press TIMER until Timer indicator light turns off.
TO VIEW OR CHANGE THE REMAINING TIME (IN HOURS):
TIMER OFF
1. Press the TEMP/TIME up or down arrow button to increase or decrease the time.
2. .erutarepmettnerrucehtroFFOemiTot
emitgniniamerehtwohslliwyalpsideht,sdnoces5retfA
TIMER ON
1. The display will show the remaining time.
2. .emitehtesaercedroesaercniotnottubworranwodropuEMIT/PMETehtsserP
3. After 5 seconds, the display will show the remaining time to Timer ON.
SLEEP
1. Press the TIMER button to choose Sleep mode. The indicator light will turn on.
2. The temperature will increase by 2˚F 1 hour after the mode is chosen. The temperature then
increases another 2˚F after 1 hour. The unit will hold this temperature for 6 hours then stops.
3. To turn off Sleep mode, press the TIMER button until the indicator light is off.
TEMP/TIME
1. ehtsserpuoyemithcaE.erutarepmetehtesiarotnottubworrapuEMIT/PMETehtsserP
TEMP/TIME up arrow button, the temperature will go up 1°F until it reaches 86°F (30°C).
2. ehtsserpuoyemithcaE.erutarepmetehtrewolotnottubworranwodEMIT/PMETehtsserP
TEMP/TIME down arrow button, the temperature will go down 1°F until it reaches 61°F (16°C).
NOTE:
After 5 seconds the display will show the current temperature.
FILTER RESET
This feature automatically notifies you that the air filter must be cleaned. The indicat or light will come on after 240
hours of operation.Clean the air filter(refer to Care and Cleaning),place it back in the front panel, and press the Filter
Reset button. The light will turn off.

HWE24VCN Parts and Functions
Domestic Air Conditioner
15
Using the Remote Cotrol
ON/OFF
MODE
SPEED
TIMER
TEMP/TIME
TEMP/TIME
Remote control may differ in appearance from the image shown.
NOTE: Remove and discard protective film prior to use. The remote control runs on one CR2025 battery (included).
Replace battery after 6 months of use,or when the remote control starts to lose power. To change battery,
first remove screw on back panel of remote.
POWER
Press ON/OFF to turn on the air conditioner.
Mode
Press MODE to choose Fan, Cool, Energy Save or Dehum.
Speed
Press SPEED to choose High, Med, Low or Auto Cool.
TIMER
To set the air conditioner to turn off after a set amount between 1 hour and 24 hours (unit must be ON):
1. .hsalflliwlenaplortnocrenoitidnocriaehtnothgilrotacidniFFOremiT.REMITsserP
2. .sruoh42otruoh1morfemityaledehtegnahcotnottubworranwodropuEMIT/PMETehtsserP
3. .noniamerlliwlenaplortnocrenoitidnocriaehtnothgilrotacidniFFOremiT,sdnoces5retfA
TO SET TIMER TO TURN ON THE AIR CONDITIONER, KEEPING PREVIOUS SETTINGS:
1. Turn on the air conditioner.
2. hsalflliwlenaplortnocrenoitidnocriaehtnothgilrotacidninOremiT.REMITsserP
3. .sruoh42otr
uoh1morfemityaledehtegnahcotnottubworranwodropuEMIT/PMETehtsserP
4. .noniamerlliwlenaplortnocrenoitidnocriaehtnothgilrotacidninOremiT,sdnoces5retfA
TO SET TIMER TO TURN ON THE AIR CONDITIONER, AND CHANGE THE PREVIOUS SETTINGS:
1. Turn on the air conditioner.
2. Adjust the mode to Fan,Cool,Energy Save or Dehum.
3. nafehttsujda,edomevaSygrenErolooCroF.woLrodeM,hgiHotdeepsnafehttsujda,edommuheDronaFroF
speed to High,Med, Low or Auto Cool.
4. Adjust the temperature between 61°F and 86°F (16°C and 30°C).
NOTE: In Fan mode, the temperature cannot be set.
5. gniniamerwohslliwyalpsiD.hsalflliwlenaplortnocrenoitidnocriaehtnothgilrotacidninOremiT.REMI
TsserP
hours before the air conditioner will turn on.
6. .sruoh42otruoh1morfemityaledehtegnahcotnottubworranwodropuEMIT/PMETehtsserP
7. Timer On indicator light on the air conditioner control panel will remain on.

HWE24VCN Parts and Functions
Domestic Air Conditioner
16
TO CLEAR TIMER DELAY PROGRAM:
NOTE: Air conditioner can be either on or off.
Press TIMER until Timer indicator light turns off.
TO SEE OR CHANGE THE REMAINING TIME (IN HOURS):
TIMER OFF:
1. .emitehtesaercedroesaercniotnottubworranwodropuEMIT/PMETehtsserP
2. remiTotemitgniniamerehtwohslliwwohslliwlenaplortnocrenoitidnocriaehtnoyalpsideht,sdnoces5retfA
Off or the current room temperature.
TIMER ON:
1. Display on the air conditioner control panel will show remaining time.
2. .emitehtesaercedroesaercniotnottubworranwodropuEMIT/PMETehtsserP
SLEEP
1. Press the TIMER button to choose Sleep mode. The indicator light will turn on.
2. The temperature will increase by 2˚F 1 hour after the mode is chosen. The temperature then increases another 2˚F
after 1 hour. The unit will hold this temperature for 6 hours then stops.
3. To turn off Sleep mode, press the TIMER button until the indicator light is off.
TEMP/TIME
• worrapuEMIT/PMETehtsserpuoyemithcaE.erutarepmetehtesiarotnottub
worrapuEMIT/PMETehtsserP
button,the temperature will go up 1°F until it reaches 86°F (30°C).
• EMIT/PMETehtdlohrosserpuoyemithcaE.erutarepmetehtrewolotnottubworranwodEMIT/PMETehtsserP
down arrow button, the temperature will go down 1°F until it reaches 61°F (16°C).
CHANGING THE AIR DIRECTION
The air directional louvers let you control the direction of the airflow. The airflow can be directed
up-down or left to right.
Vent: The Fresh Air vent allows the air conditioner to recirculate inside air, draw fresh air into the
room, and exhaust stale air to the outside.
4-Way Air Flow Vent

7. Abnormity Diagnose
If air conditioner does not operate:
Check if unit is plugged in. The plug may have come loose.
Check if the unit is in the :Off” mode.
Air from air conditioner is warm:
The A/C setting may need to be raised.
Ice formation on cooling coils:
The outside temperature is too cold. Set the unit on “fan only” setting to defrost ice.
The temperature setting may be too cold.
The unit BTU may be too high for the room.
Air conditioner is working but room is not cooling:
The room may have appliances that produce heat. Use an exhaust fan to remove excess heat.
Redirect the airflow. Remove any obstacles.
All doors and windows need to be closed so cool air does not escape the room.
The air filter may need cleaning.
The unit BTU may be too low for the required cooling area.
On extreme hot & humid days, air conditioners may take a little longer to cool.
Vent may be in the open position. Vent has to be closed for optimum cooling.
Air conditioner is making noise when cooling:
You may hear sounds of air movement, water, compressor clicking on and off or window vibrations.
Please read Operating Guide - Normal Operating Sounds.
Water in the air conditioner cabinet:
This is normal, as your air conditioner not only cools but also dehumidifies the air. If there is water dripping
inside the room, check the installation of the unit. The unit may need to be reinstalled.
HWE24VCN esongaiDytimronbA
Domestic Air Conditioner
17

Trouble shooting:
Indoor Possible Reasons
E0 1) Room-temperature sensor is broken.
2) Indoor PCB is damaged.
E1 1) Connection is bad.
2) Indoor PCB is damaged.
E0: Room temperature sensor malfunction
Firstly check whether
Terminal CN2 on the
mainboard contact well
or not?
Pull out the terminals on
the mainboard and
reinsert them.
Pull the sensor out of the mainboard
1) Measure the value of resistance
between its two jumpers
2) Measure the temperature at the room
temperature sensing head.
Check the specifications of the sensor
to decide whether the sensor is
damaged or not?
Replace with new
sensor.
The PCB is broken.
Replace with new PCB
No
Yes
Yes
No
HWE24VCN esongaiDytimronbA
Domestic Air Conditioner
18

HWE24VCN esongaiDytimronbA
Domestic Air Conditioner
19
E1: Bottom malfunctions
Repair the plastic keystrokes of the
electric box to keep them away from
the keystroke of mainboard.
Replace the indoor
PCB with new one.
Yes
No
Check whether the keystroke
can't work due to extrusion.