Mitsubishi Electric MSZ / MSY / MUZ / MUY GL NA series error code 7 blinks, 2.5 s OFF
Inverter or control board over-temperature
Quick answer
On Mitsubishi Electric MSZ / MSY / MUZ / MUY GL NA series, 7 blinks, 2.5 s OFF is a fault. It means inverter or control board over-temperature. A first thing to check: A dirty or blocked outdoor coil reducing airflow over the inverter heat sink.
- Applies to
- Mitsubishi Electric MSZ / MSY / MUZ / MUY GL NA series
- Mitsubishi Electric MR SLIM GL series split codes · Mini Split
- Type of code
- Fault
- Urgency: Needs attention soon
- First safe check
- Clean the outdoor coil and clear the discharge grille, since airflow over the electronics is the first thing to rule out.
What 7 blinks, 2.5 s OFF means on this model
The electronics got too hot and the unit shut down. The thresholds differ by model size: fin temperature 167 to 187 F, which is 75 to 86 C, on the GL09 through GL18 but 167 to 176 F, which is 75 to 80 C, on the GL24, and P.C. board temperature 162 to 185 F, which is 72 to 85 C, on the GL09 through GL18 but 158 to 167 F, which is 70 to 75 C, on the GL24. The inverter LED blinks seven times for this one.
Symptoms you will notice
- Upper lamp blinks seven times after a three second hold, no beep
- The fault appears in hot weather or after the unit has run a long time
- The outdoor unit is in a tight space, against a wall, or under a roof overhang
- The system works in mild weather and fails when it is hot
Common causes
The code tells you what the control detected, not which part failed. These are the causes we see most often, roughly in order of likelihood:
- A dirty or blocked outdoor coil reducing airflow over the inverter heat sink
- A failed or slow outdoor fan motor
- A failed condenser fan capacitor
- The unit installed in a confined space with poor discharge airflow
- An ambient temperature beyond the unit rating
- Debris blocking the unit discharge grille
- A failed inverter heat sink or board that is running hotter than it should
What you can safely check
These are homeowner-level checks. None of them need you to open a live electrical compartment or work on gas.
- Clean the outdoor coil and clear the discharge grille, since airflow over the electronics is the first thing to rule out.
- Confirm the outdoor fan runs at full speed.
- Check the unit clearance and whether it is reflecting heat off a wall or under a roof.
- Check whether the fault follows a run of unusually hot weather, which would point at installation rather than a failed part.
Do not do these
- ×Do not keep restarting. Each attempt runs the electronics at a temperature that has already damaged them.
- ×Do not enclose or box the outdoor unit. That removes the discharge airflow this protection depends on.
- ×Do not spray the coil with a high pressure hose, which bends the fins and makes the airflow problem worse.
When to call a technician
Book a technician, do not keep resetting it
This fault will not clear on its own. Every power cycle gives the control one more failed attempt, and repeated attempts are what turn a cheap part replacement into a seized or contaminated system.
- The refrigerant circuit is sealed and legally requires licensed handling. Opening it without certification releases refrigerant and can put the whole system in violation of regulation, so a low-pressure or high-pressure fault on this equipment is a call-out, not a weekend job.
- If the appliance has stopped mid-cycle, is making a noise you have not heard before, or smells burnt, stop reading here and call. Those are symptoms of something the fault code does not describe well enough.
Coil cleaning, clearing debris and checking clearances are reasonable homeowner tasks. Fan and board work is a technician job.
What it costs to fix
Parts
Outdoor fan motor $300 to $700. Fan capacitor $30 to $80. Inverter P.C. board $500 to $1,200.
Labor
One to four hours, from cleaning through to a board replacement.
DIY or technician
Coil cleaning, clearing debris and checking clearances are reasonable homeowner tasks. Fan and board work is a technician job.
Typical US part and labor ranges, 2026. They vary by region, model and contractor, so treat them as a planning figure, not a quote.
Scope of this code
- Code table
- Mitsubishi Electric MR SLIM GL series split codes
- Models in scope
- Mitsubishi Electric MSZ / MSY / MUZ / MUY GL NA series
- Checked
- Confirm on your own unit
- Find the model number on the data plate, then check this code in the service manual for that model. Manufacturers revise code tables between model years, and a revised board can renumber a fault.