JustAnswer
justanswer.com › australia-whitegoods › 80fux-code-u1-showing-flashing-dikin-air-con-controller.html
How to Fix Daikin Error Code U1: Expert Solutions
Hi, welcome to Just Answer. My name is ***** ***** I look forward to helping you! The U1 code means there was a drop or loss of voltage. Check the incoming power supply connections for signs of heat or burning.
Reddit
reddit.com › r/hvac › help - daikin 20kw ducted system is throwing a u1 fault code
r/HVAC on Reddit: HELP - DAIKIN 20kw ducted system is throwing a U1 fault code
October 31, 2025 -
DAIKIN 20kw ducted system is throwing a U1 fault code.
We did change the power and incorrectly orientated the phases but have rectified this issue but we can’t clear the code to restart the unit.
I have continuity checked all the fuses on the PCB’s and carried out numerous power off resets including one over night but the fault code persist.
I think the indoor controller is just telling the out door unit it has a problem at this point.
Have cleared the fault off the remote but the out door unit still won’t start.
PCB’s don’t have any visible issues.
Any ideas on what to try next?? We really need this thing going as it’s being used for temperature control in a factory.
HELP - DAIKIN 20kw ducted system is throwing a U1 fault code
Attention! It is always best to get a qualified electrician to perform any electrical work you may need. With that said, you may ask this community various electrical questions. Please be cautious of any information you may receive in this subreddit. This subreddit and its users are not responsible for any electrical work you perform. Users that have a 'Verified Electrician' flair have uploaded their qualified electrical worker credentials to the mods. If you comment on this post please only post accurate information to the best of your knowledge. If advice given is thought to be dangerous, you may be permanently banned. There are no obligations for the mods to give warnings or temporary bans. IF YOU ARE NOT A QUALIFIED ELECTRICIAN, you should exercise extreme caution when commenting. I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns. More on reddit.com
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October 31, 2025[Daikin VRV] [220 VAC] U4-01 Error Code Help
They have their own specific setup that I can’t remember (too many schematics in my brain). If it runs for a little bit and then shuts off for a while, kicks on for a bit and yada yada, check your condensate line, might be tripping a “safety switch.” Thats a quick fix, vacuum out the line. Check around the condenser and see if there’s a bunch of droppings. Rodents like to keep warm and chew on wires, those little bastards. Could be a number of things. But I’d start with the condy line. More on reddit.com
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September 6, 2024HELP - DAIKIN 20kw ducted system is throwing a U1 fault code
U1 error says youre missing a phase. verify you have all your phases, at the correct voltage. after that, its time to call tech support. More on reddit.com
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October 31, 2025HELP - DAIKIN 20kw ducted system is throwing a U1 fault code
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Daikin
daikin.com › products › ac › services › error_codes
Error Codes | After Sales Service | Air Conditioning and Refrigeration | Daikin Global
Error Code Search offers information on the cause of the malfunction and the status of your air conditioner by entering the error code. Error Code Search List of Error Codes(0.1MB) Please refer to "How to Check Error Codes" for step-by-step instruction to check the error codes.
RemoveandReplace.com
removeandreplace.com › home › home air conditioning › daikin air conditioner ac error codes
DAIKIN Air Conditioner AC Error Codes
December 22, 2022 - U0 System Shortage of refrigerant or EEV failure U1 System Negative phase, Open phase U2 System Power supply insufficient U3 System Wiring check operation not executed U3 System Mismatch of indoor and outdoor units – Split only U4 System ...
JustAnswer
justanswer.com › hvac › roaz1-u1-error-code-daikin-controller-not-know.html
Daikin U1 Error Code: Troubleshooting Guide & Solutions
I am getting error code U4 on my Daikin air conditioner. It was working OK, when I switched on 'mouth' would open then, My daikin air conditioner is not running but the thermostat works. How do I get it to work. HVAC Technician: André R. I am the technician, and I will be happy to assist you. HVAC Technician: André R. ... HVAC Technician: André R. Certainly! Here’s a sequence of troubleshooting steps you can try to resolve the U1 error code on your air conditioning unit when you have time:
Airway Group
airway-group.co.uk › home › help & advice › daikin air conditioning fault codes explained [infographic]
Daikin Air Conditioning Fault Codes Explained [Infographic] | Airway
April 2, 2026 - U1 – Reverse phase – The three phase power supply has been reversed. U2 – Open phase or power voltage imbalance – There may be an open phase or a voltage imbalance in the power supply.
JustAnswer
justanswer.com › australia-whitegoods › 58gw0-error-code-u1-solution-daikin-model-brc1e61-indoor-unit.html
How to Fix Daikin Error Code U1: Expert Solutions and Troubleshooting
The code U1 indicates a reverse phase or an open phase, suggesting there may be a fault or damage due to a power outage.
Star-supply
star-supply.com › content › Daikin-Troubleshooting Codes.pdf pdf
Trouble Shooting www.climatecenter.co.uk Daikin Trouble Shooting Guide
Capacity setting error · Incorrect ... Codes · Fault Code · Definition · Supposed Causes · Split · Skyair · VRV · Package · HRV · U0 · Shortage of refrigerant · Undercharged, EEV fault, faulty sensor · • · • · • · • · U1 ·...
Daikin
my.daikin.eu › content › dam › DASW › supportavdelningen › Felkoder_SM-TS3errorcode_chart.pdf pdf
Simple Self-Diagnosis by Malfunction Code After Sales Service Division (SM-TS3)
U1 · Reverse phase, open phase · Power supply reverse phase · T phase open phase · Defective outdoor unit PCB (A1P) k k k k k k k · U2 · Malfunction of power supply or · instantaneous power failure · Abnormal power supply voltage · Instantaneous power failure · Defective main circuit ...
Daikin ONE
daikinone.com › smart_thermostats › oneplus › pros › PhaseTwoErrorCodes.pdf pdf
Climate Talk Fault Code Dealer error code Possible causes Corrective actions
Thermostat internal communication error · ClimateTalk coprocessor was not anle to start. •Conduct a warm start of the thermostat. •Call Daikin support at 1-855-DAIKIN1(option 1) •Replace thermostat if needed · Thermostat · Critical · Internal hardware error ·
Scribd
scribd.com › document › 425197901 › Daikin-error-code-pdf
Daikin VRV Error Code Troubleshooting Guide | PDF | Manufactured Goods | Electrical Engineering
U1 − 01 Reverse phase/open phase for power supply (Master) U1 − 04 Reverse phase for power supply [with power supply turned ON] (Master) U1 − 05 Reverse phase/open phase for power supply (Slave 1) Refer to the “U1” flow chart of each ...
CoolAutomation
coolautomation.com › blog › daikin error codes: comprehensive breakdown
Daikin Error Codes (Malfunction Self-Diagnosis)
July 20, 2025 - Easily identify Daikin HVAC system faults with this complete list for simple self-diagnosis & troubleshooting. Includes VRV, SkyAir, HRV systems, and more.
Airconditioningmackay
airconditioningmackay.com.au › home › daikin air conditioner error codes
Daikin Air Conditioner Error Codes and Troubleshooting Faults
January 22, 2026 - The list below features all the malfunction error codes for Daikin air conditioners and their potential causes.
Glow HCE
glowhce.com.au › home › daikin fault codes – system errors
Daikin System Error Codes | Simple Self Diagnosis | Daikin Fault Codes
October 13, 2023 - For error codes beginning with A or C, find causes here · For error codes beginning with E, F, H, J, L, M or P, find causes here
Facebook
facebook.com › groups › electricalenggtechnology › posts › 1704032466751428
How to recfy Daikin inverter centelis AC error code U1 and ...
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Perthaircon
perthaircon.com.au › home › daikin error and fault codes
Daikin Error and Fault Codes – Daikin Air Conditioning Perth by Airpro Air Conditioning
J1 Outdoor Malfunction of pressure ... sensor malfunction PJ Outdoor Failure of capacity set resistor U0 System Shortage of refrigerant or EEV failure U1 System Negative phase, Open phase U2 System Power supply insufficient U3 System Wiring check operation not executed U3 ...
Arlington Air Conditioning Services
arlingtonairconditioningheating.com › arlington hvac audit › air conditioner error codes › 99 daikin aircon error codes + troubleshooting
Daikin AC Error Codes & Troubleshooting (2026 Interactive Decoder)
April 21, 2026 - ⚠️ Pro Safety Tip: While issues like cleaning blocked filters to stop a freeze-up (A5) or topping up refrigerant (U0) are straightforward fixes, errors involving the inverter PCB (L1), reverse phase wiring (U1), or Intelligent Power Module ...
HVAC Toolkit
hvactoolkit.org › home › resources › error codes › daikin
Daikin Error Codes - Complete Fault Code List & Solutions | HVAC Toolkit
Complete Daikin error code list for mini-splits, VRV systems, and air conditioners. Find meanings, causes, and troubleshooting solutions for all Daikin fault codes.
Reddit
reddit.com › r/askelectricians › help - daikin 20kw ducted system is throwing a u1 fault code
r/AskElectricians on Reddit: HELP - DAIKIN 20kw ducted system is throwing a U1 fault code
October 31, 2025 -
DAIKIN 20kw ducted system is throwing a U1 fault code.
We did change the power and incorrectly orientated the phases but have rectified this issue but we can’t clear the code to restart the unit.
I have continuity checked all the fuses on the PCB’s and carried out numerous power off resets including one over night but the fault code persist.
I think the indoor controller is just telling the out door unit it has a problem at this point.
Have cleared the fault off the remote but the out door unit still won’t start.
PCB’s don’t have any visible issues.
Any ideas on what to try next?? We really need this thing going as it’s being used for temperature control in a factory.
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Attention! It is always best to get a qualified electrician to perform any electrical work you may need. With that said, you may ask this community various electrical questions. Please be cautious of any information you may receive in this subreddit. This subreddit and its users are not responsible for any electrical work you perform. Users that have a 'Verified Electrician' flair have uploaded their qualified electrical worker credentials to the mods. If you comment on this post please only post accurate information to the best of your knowledge. If advice given is thought to be dangerous, you may be permanently banned. There are no obligations for the mods to give warnings or temporary bans. IF YOU ARE NOT A QUALIFIED ELECTRICIAN, you should exercise extreme caution when commenting. I am a bot, and this action was performed automatically. Please contact the moderators of this subreddit if you have any questions or concerns.
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Try r/HVAC . As far as the manual says, just reversing the phase rotation should clear the fault.