Air Conditioner Error Codes, What E5, E6, E9 and P4 Mean

Air conditioner error codes are how a unit tells you which part has a problem. Your air conditioner has stopped and the display reads E5. You search it, find a confident answer, and book a repair for the wrong thing.

Here is the problem with every generic error code list on the internet. E5 means one thing on a Daikin, something else on a Gree, and something else again on a Braemar. The letter and number are not a universal language. They belong to whoever built the unit.

This page shows you what the common codes mean on each brand, using manufacturer documentation, and tells you plainly where a brand publishes nothing at all.

The same code, four different meanings

Before looking anything up, this is worth seeing.

What E5 means by brand

• Daikin. Overload of the compressor, described as OL started. Outdoor unit.
• Teco. Not in the published table. Teco documents dF, E1, E2, E3, E6 and E7 on its splits and does not define E5.
• Haier. Not published in Haier Australia documentation.
• Kelvinator. Listed as a code the display can show, with no meaning published.
• Gree. Referred to as part of the E code family without a published meaning.

Daikin is the only one of those that publishes a meaning, and it is a serious one. A compressor overload is not a homeowner repair.

What E6 means by brand

• Daikin. Faulty compressor start up.
• Teco. Outdoor tube temperature sensor error.
• Mitsubishi Electric. Appears in the wireless receiver check code list as an indoor and outdoor unit communication error, paired with E7.
• Actron Air. Fault discharge high temperature, which Actron links to being low on refrigerant, on its classic ducted range.
• Haier. Not published.

Two very different problems share that code. On a Daikin it points at the compressor. On a Teco it points at a sensor, which is a far smaller job.

What E7 means by brand

• Haier. Communication fault between indoor and outdoor units. This is the one people search for most.
• Teco. EEPROM communication error.
• Daikin. DC fan motor fault, outdoor.
• Dometic. Outdoor temperature sensor failure.
• Mitsubishi Electric. Indoor and outdoor unit communication error.

A Haier showing E7 has two halves of a system that have stopped talking to each other. The indoor fan often still runs while nothing useful happens to the temperature, which is exactly what a communication fault looks like from the lounge room.

What E9 means by brand

• Dometic. Compressor drive or IPM module fault.
• Braemar ducted reverse cycle. Indoor fan motor error.
• Actron Air. On its classic ducted range, high or low pressure, or a phase error.
• Daikin. Not in the consumer code list.
• Teco and Haier. Not published.

Every brand that does publish an E9 puts it somewhere expensive. Compressor drive, fan motor, or a pressure fault. None of those is a reset away.

What P4 means by brand

• Daikin. Faulty inverter circuit heatsink temperature sensor.
• Dometic. Discharge tube overheat protection.
• Mitsubishi Electric. Drain sensor error, in the wireless receiver check code list.
• Kelvinator and Gree. Listed as part of the P code family with no meaning published.

The P codes are usually protections rather than component failures. The unit has detected a condition it does not like and stopped rather than damage itself.

What about EL codes?

Here is an honest answer rather than a confident one.

Dometic publishes EL as a communication failure on the bus that links the parts of the system together.

Beyond that, an EL code followed by two digits does not appear in any manufacturer documentation that can be verified for the Australian brands covered here. It circulates widely on repair forums attached to specific meanings. Those meanings are not something a manufacturer has published, so this page will not repeat them.

If your display reads an EL code, write down exactly what it shows, including any digits, and report it. Do not act on a forum answer for a code nobody can source.

Codes that are not faults at all

Several brands use the same display to tell you about ordinary operation, and these get reported as faults constantly.

Two of those deserve special mention because they cost people money.

Demand response. On Kelvinator and Actron, and on Mitsubishi Electric systems fitted with the enabling device, your electricity provider can limit the air conditioner during peak demand. The unit runs weakly on the hottest afternoon of the year and no technician can do anything about it. If your display shows a D or dr code, that is what is happening.

Haier F25 during self clean. Haier documents F25 as a discharge temperature sensor failure in its service material, and separately tells owners that if the outside temperature drops below zero, F25 may appear during self cleaning as a normal protective measure. Same code, and the context decides whether it matters.

How to read the code in the first place

Not every brand puts the code on a screen. Some make you count flashes.

• Daikin. Hold the timer cancel button, or Cancel on newer remotes, for about five seconds. Press repeatedly and listen. A long continuous beep means the code on screen is the stored one. A short beep or two quick beeps means keep going.
• Panasonic. Hold the CHECK button for five seconds with something pointed. Press the timer up or down button until the unit beeps for about four seconds and the power light stays on for 30.
• Mitsubishi Electric wireless receivers. Count the beeps or lamp flashes. One flash is P1, two is P2 or P9, three is E6 or E7, and so on.
• Mitsubishi Heavy Industries. The run light and the timer light flash a sequence together. The mapping differs by model series, so count both and report them.
• Fujitsu. Codes come from the lamps, not the remote display, on wireless models. The full tables are in trade documentation rather than consumer manuals.
• Toshiba wired controllers. The check code and indoor unit number flash on the display.
• Kelvinator, Teco, Gree, Haier, Dometic. The code appears directly on the indoor unit or panel display.

The brands that publish nothing

This is the part no other page will tell you, and it saves you chasing an answer that does not exist.

• Toshiba does not publish a consumer facing check code table. Its fault code material is aimed at installers.
• Fujitsu keeps its blink count tables in a trade document, and they are model specific.
• Braemar publishes no numbered fault code table for its gas heaters at all. A single code appears once in the documentation with no meaning attached.
• Bonaire deliberately withholds code meanings from owners. Its manuals say to have the code ready for the service operator instead.
• Kelvinator and Gree list E, P and F code families in their manuals without defining the individual codes.
• Teco publishes codes for its fixed speed splits and portables but not for its inverter range.

If your brand is on that list, every code meaning you find online came from somewhere other than the manufacturer. Some of it will be right. None of it can be checked.

What to do with a code

1. Write it down exactly. Letters, numbers, and whether anything is flashing.
2. Check this page for your brand rather than for the code on its own.
3. Rule out the non faults. Defrost, demand response, cleaning cycles, freeze protection.
4. Check the filters. Several protection codes across every brand are triggered by restricted airflow, and that is the one cause you can fix yourself.
5. Wait, then power cycle. Kelvinator says to wait ten minutes first. Daikin says to switch the breaker off for twenty. Most brands then need three minutes before the compressor will run.
6. If the code returns, report it with the brand. E7 on a Haier and E7 on a Daikin need different technicians looking at different parts.

Codes that mean stop now

• Anything pointing at the compressor. Daikin E5 and E6, Dometic P9 and E9, Actron E6.
• Refrigerant related codes. Daikin U0, Kelvinator EC, Actron E6 on classic ducted.
• Pressure protections. Braemar E1 and E3, Actron E09 and E11, Panasonic H98 and F95.
• Any code accompanied by a burning smell. Switch off at the breaker before anything else.
• Any code that trips the breaker when you restore power.

Why brands do not share a code system

It seems like an obvious thing to standardise, and there is a reason it never happened.

An error code is not a description of a symptom. It is a reference into the service documentation of the manufacturer, pointing a technician at a specific board, sensor or protection on a specific platform. The code is only meaningful alongside the wiring diagram, the sensor positions and the control logic of that particular system.

That also explains why the same letter and number turn up everywhere. Manufacturers number their faults from the start of their own list, so E1 is simply the first entry on whatever that brand decided to number first. On a Teco that happened to be the room temperature sensor. On a Braemar ducted system it happened to be high pressure protection.

It gets more tangled still, because several brands share a manufacturing platform. A unit sold under one badge in Australia may carry the code set of the factory that built it rather than the brand on the front. That is part of why a code sometimes matches the table of a completely different brand and sometimes does not.

What a code cannot tell you

Worth setting expectations, because a code answers a narrower question than people hope.

A code names what the unit detected. It does not name the cause. A freeze protection code tells you the indoor coil got too cold. It does not tell you whether that was a blocked filter, a failing fan, a closed zone, or low refrigerant, and those are four very different jobs at four very different prices.

Equally, a unit can be badly wrong with no code at all. A system slowly losing refrigerant often runs happily for a season, cooling worse each month, and never trips anything. Nothing on the display will warn you. The only symptom is that it stops keeping up.

So a code is a starting point for a technician rather than a diagnosis, and no code does not mean no problem.

Reading the code instead of guessing at it

An error code is the most useful thing your air conditioner will ever tell you, and it is worth almost nothing without the brand attached to it. E5 on its own is not information. E5 on a Daikin is a compressor overload, and that is a sentence a technician can act on before they arrive.

Write the code down, find your brand above, and rule out the handful that are not faults at all. If the symbols on your remote are the puzzle rather than a code, our guide to air conditioner symbols covers those by brand.

When the code points at the compressor, the refrigerant circuit or a pressure protection, that is the point where guessing costs more than asking. We send a licensed technician who works on split, multi head and ducted systems across Melbourne, and the price is confirmed before any work starts. It is also worth knowing how often you should service your air conditioner, since a good share of the protection codes above are triggered by dirt rather than by failure.

Some codes point at the compressor, which is the one repair worth pricing before you commit, and our guide to compressor replacement cost in Melbourne covers the range.

Once you have the code, the diagnosis is quick. Our air conditioner service in Melbourne works across every brand on this page, and you can request a quote with the code written down.