Generac Generator Alarm: Overload — Causes & Fixes

What Does This Error Mean?

Generac Alarm: Overload triggers when the total wattage of connected appliances exceeds the generator's rated output. The unit shuts down to protect its alternator and engine windings from heat damage. Disconnect all loads, wait 3 minutes, restart, then reconnect appliances one at a time until the total stays within the rated wattage.

Affected Models

Generac Guardian 7043
Generac Guardian 7172
Generac PowerPact 7500E
Generac GP3500iO
Generac iQ3500

Common Causes

Too many appliances connected simultaneously, exceeding rated watts
A large motor (air conditioner, well pump, fridge compressor) drew heavy starting surge watts that briefly exceeded capacity
A short circuit or faulty appliance on the output circuit pulled excessive current
Generator derated in high altitude or extreme heat, reducing effective capacity below nominal rating

How to Fix It

Shut off or unplug all connected appliances immediately

The overload alarm shuts the generator down to protect it. Before restarting, make sure every load is disconnected from all outlets. Do not restart with anything still plugged in.
Wait 3–5 minutes before restarting

The engine and alternator need a short cool-down period after an overload event. Attempting to restart immediately may trigger the alarm again before the thermal protection has reset.
Restart the generator and confirm it runs cleanly with no load

Start the generator and let it run at idle for 1–2 minutes with nothing connected. The alarm should be clear. If the alarm returns with no load attached, there may be an internal fault — stop the unit and contact a service technician.
Reconnect appliances one at a time, starting with the lowest wattage items

Add loads gradually and check the generator is not struggling (listen for engine laboring). Add high-draw items like air conditioners or refrigerators last. Never exceed 80–90% of the generator's rated wattage to leave headroom for motor starting surges.
Calculate the total wattage of your connected loads

Check the label on each appliance for running watts and starting watts. Multiply starting watts (not running watts) by 1.5–3 for motor-driven items. The sum of all starting watts at the worst moment must not exceed the generator's surge capacity.

Frequently Asked Questions

Will the overload alarm damage my Generac generator?

The alarm is a protection feature, not a sign of damage. A single overload event that the protection shuts down quickly does not typically cause permanent harm. Repeated overloads that are manually bypassed or ignored can damage the alternator windings over time. Always respect the overload alarm.

How do I find my Generac generator's rated wattage?

The rated wattage is printed on the generator's specification label, usually located on the control panel or on a sticker on the housing. It is also listed in the owner's manual. The figure shown is running watts — starting (surge) watts are typically 10–20% higher.