$49 / month O.A.C Including Install
$49 / month O.A.C Including Install

What Do AC Error Codes Mean?

24 / 7 Emergency Service Available. Call Us Now: 1.844.894.6832


[BACK]
What Do AC Error Codes Mean?

Posted On: June 2, 2024

What Do AC Error Codes Mean?

Air conditioning (AC) units can display error codes when something goes wrong. These codes are specific to the manufacturer and model of the AC unit, but here are some general explanations for common AC error codes:


General AC Error Codes

  1. E1/E2/E3/E4: These codes often indicate issues with sensors:


    • E1: Room temperature sensor error.
    • E2: Indoor coil sensor error.
    • E3: Indoor fan speed malfunction.
    • E4: Outdoor coil sensor error.
  2. F1/F2/F3: These codes are usually related to the frequency drive or the main control board.


    • F1: Indoor unit PCB (Printed Circuit Board) error.
    • F2: Outdoor unit PCB error.
    • F3: Outdoor ambient temperature sensor error.
  3. H1/H2/H3: These codes generally indicate protection errors.


    • H1: Defrosting mode.
    • H2: Overload protection of the compressor.
    • H3: High-temperature protection of the compressor.
  4. P1/P2/P3: These codes typically relate to pressure or system malfunctions.


    • P1: High pressure protection of the system.
    • P2: Low pressure protection of the system.
    • P3: Protection against lack of refrigerant or malfunction in the refrigerant system.
  5. L1/L2/L3: These codes can be related to electrical issues.


    • L1: Phase loss or imbalance.
    • L2: Overcurrent protection.
    • L3: Voltage error or under-voltage protection.

Manufacturer-Specific Error Codes

LG

  • CH 01: Indoor unit room temperature sensor error.
  • CH 02: Indoor unit pipe temperature sensor error.
  • CH 03: Communication error between indoor and outdoor units.

Daikin

  • U0: Low refrigerant.
  • U4: Transmission error.
  • E1: Circuit board malfunction.

Mitsubishi

  • P1: Abnormal rise in pressure.
  • P8: Outdoor unit air temperature sensor error.
  • E0: Inverter/compressor malfunction.

Samsung

  • E101: Communication error.
  • E121: Indoor temperature sensor error.
  • E154: Outdoor coil sensor error.

What to Do When an Error Code Appears

  1. Consult the Manual: The best source of information is the user manual or service manual for your specific AC model.
  2. Reset the Unit: Sometimes, resetting the unit by turning it off and on again can clear the error.
  3. Check for Obvious Issues: Ensure that filters are clean, vents are not blocked, and that there is no visible damage to the unit.
  4. Call a Professional: If the error persists, it's best to contact a professional technician. They can diagnose and fix the issue safely.

Understanding these codes can help you determine whether the issue is something simple that you can fix yourself or if you need to call a professional for assistance.



[BACK]

See What Our Customers Are Saying:

by Robert, Pickering on Twintech Heating and Cooling

Had new furnace installed and ran into some difficulties but the contractor responded in a timely and efficient manner - after further service calls were made, a reasonable resolution was found.

by Brian Burns, Whitby on Twintech Heating and Cooling

The work was done quickly efficiently neatly and professionally. Pleased with the service, information, product, and the company.

by Geoff, Port Perry on Twintech Heating and Cooling

Great sales member named Dave came in told us some amazing items and how they would be priced installed an all. We couldn’t believe it! The next day the ac was installed, that day one employee named Greg told us that our furnace was working way to hard and was causing us to use way too much gas. So two days later they came in an installed a new furnace!

by MB, Ajax on Twintech Heating and Cooling

Installation was done quickly and professionally. The new furnace is quiet and provides even heat.

by Richard from Oshawa on Twintech Heating and Cooling

They removed and discarded old furnace. Installed new furnace. Installed air intake pipe, that had never been installed by builder, no charge. Replaced loose hose on floor with hard pipe and rerouted it to drain, no charge. Almost 33% cheaper then quote from Enercare, which was the company we dealt with and had insurance with for 8 years. No yearly fee for cleaning/insurance, saves 300 a year. Courteous, professional, fast, and friendly. My wife and I have been recommending them to everyone we know and meet, and will continue to do so. Thanks for everything, Twintech!!!

by Darcy from Pickering on Twintech Heating and Cooling

This company was great to deal with. Our furnace went down and they installed a new furnace the next day with a lot of professionalism!

by gillian hooton from Uxbridge on Twintech Heating and Cooling

Finally! An honest company with highly knowledgeable and informative staff. Had a furnace service and found multiply errors in our system from an amateur installer. Very fair price to correct problems and will definitely use again.

by dflynn in Ajax on Twintech Heating and Cooling

Had to replace the heating & a/c unit in a condo apartment dwelling. this company recommended by the property manager and president of the condo building. found their workmanship and attention to details very good and very thorough. were able to resolve small problems and situations and happy to feel the heat in my unit. it's pricey, but happy was done by a very professional service. thank you.

by alisiena from Toronto on Twintech Heating and Cooling

Fantastic team. Completed the job as per the specifications and in under 3 hours. Highly recommended Twintech.

by David from Toronto on Twintech Heating and Cooling

During the summer, I previously hired TwinTech to replace my air conditioner when it failed. They did an excellent job so when I decided to proactively replace the furnace I contacted them. The furnace I had was 22 years old and showed signs of internal leakage. It still worked but rather than wait to have it fail in cold weather, I decided to purchase a higher efficiency model before it failed and take advantage of energy efficiency rebates. TwinTech offered very useful advice on the make and model of furnace to choose including high efficiency and variable speed motor. The price was reasonable, TwinTech arrived at the allotted time, installed the new furnace (including some re-routing of exhaust lines since the existing ones were too close to other vents), removed the old furnace, tested the installation and cleaned everything up. Overall, it was a good experience, they did a great job and the new furnace is working well.

Related Links:
oshawa gas furnace problems, ac service call, pickering hvac prices, local ac services, ajax furnace inspection, ac repair services, whitby furnace replacement, furnace repairs pickering, oshawa hvac furnaces, central ac service, ac unit maintenance, pickering gas furnace problems, ac installation near me, ajax hvac repair, hvac repairs, ac contractors, ac repair and service, whitby furnaces, residential furnace, residential ac repair, pickering hvac furnace, pickering furnace service, pickering furnaces, oshawa furnace inspection, oshawa furnaces, nearby ac repair,


See What Our Customers Are Saying:

by Robert Rogers on Twintech Heating and Cooling

Very pleased with the professional service that TwinTech Heating and Cooling provided in replacing my furnace. I got several quotes from different service providers. Their price was excellent and they explained the features very well. We are very glad we went with TwinTech and highly recommend their services.

by Robert Mizuno on Twintech Heating and Cooling

We were new homeowners in need of a second opinion. TwinTech Heating & Cooling were Amazing and professional. Very knowledgeable and great service all around. Recommend to anyone looking for honest and reliable services. Treated with respect and care. Thank you Greg, Mitch and Bob!

by Ruth on Twintech Heating and Cooling

TwinTech is an excellent and honest company! I called them for a second opinion after being told by another company that I needed to replace my furnace. Turns out this was not the case at all! I did not need a new furnace. TwinTech did not push to make an unnecessary sale and saved me from a huge expense. Bob and Mitch were extremely professional and above all honest! I definitely recommend TwinTech!

by Anna Chin on Twintech Heating and Cooling

Amazing experience with TwinTech Heating & Cooling! Their team was professional, knowledgeable, and efficient from start to finish. They installed my new furnace quickly and left everything spotless. The technicians took the time to explain everything and made sure I was comfortable with the system before they left. Great customer service and fair pricing. I highly recommend them for anyone needing HVAC services!

by Connor Agnew on Twintech Heating and Cooling

Great experience all around. Bob was sharp and easy to talk to, and Greg handled the installation perfectly. Would hire them again in a heartbeat.

Why You Should Maintain Your HVAC Systems Regularly

  • SUBMITTED BY:
  • TWINTECH HEATING & COOLING
  • - July 7, 2018

One of the most important money-saving practices of home ownership is having your HVAC systems regularly maintained. Having your HVAC systems maintained lets them work at peak efficiency all year-round and it also saves you money in terms of utili

Read More

Expert HVAC Services in Pickering

  • SUBMITTED BY:
  • TWINTECH HEATING & COOLING
  • - March 16, 2025

When it comes to heating and cooling services in Pickering, Twintech Heating and Cooling stands out as a trusted provider with years of experience in the industry. Whether you need a furnace repair, air conditioning installation, or routine HVAC m

Read More

Internal Furnace Issues

  • SUBMITTED BY:
  • TWINTECH HEATING & COOLING
  • - October 9, 2024

When addressing internal furnace issues, it's important to recognize common problems and their potential causes. Here’s a breakdown of some key internal furnace issues and how they can be resolved: 1. Clogged or Dirty Filters Cause

Read More

Preventing a Total Furnace Breakdown

  • SUBMITTED BY:
  • TWINTECH HEATING & COOLING
  • - September 27, 2024

Preventing a total furnace breakdown requires regular maintenance and attention to key components of your heating system. Here are some tips to help: 1. Schedule Regular Maintenance Have a professional inspect and service your furnace at least

Read More