Deye F34: AC Overcurrent Fault
F34 is an AC overcurrent on the inverter's output. In plain terms, something is drawing more current than the output is allowed to deliver, usually too much load on the backup (EPS) circuit. It's a close cousin of F18 and is normally fixed by trimming the load.
What usually causes F34
- Too much load on the backup output, above the inverter's rating.
- A surge when a motor, pump or compressor starts.
- A faulty appliance drawing abnormal current.
The safe fix, step by step
- Reduce the load. Switch off heavy appliances on the backup circuit, motors and heaters first.
- Power-cycle. AC output breaker off, wait 60 seconds, back on. If it persists, also turn the DC isolator off, wait 5 minutes, and restart both.
- Add loads back one at a time. Re-enable appliances one by one to find the one that trips it.
- Stay within the rating. Confirm the total backup load is below the inverter's rated output power.
When to call a professional
If F34 returns with little or no load after a proper restart, the issue may be internal rather than an overload. Stop resetting it and contact your installer.
Related Deye codes
FAQ
What's the difference between F18 and F34?
Both are AC-side overcurrent faults handled the same way: reduce load, restart, and find the culprit appliance. Treat them with the same approach.
It trips when my pump or A/C starts. Why?
Motors draw a large inrush current at startup. If that surge exceeds the limit, F34 trips. Staggering heavy startups or checking that the appliance is within your inverter's rating usually solves it.
Sources
- Deye Hybrid Inverter User Manual (F34 = "AC Overcurrent fault"; keep backup load within the permitted power range).
- Deye dealer technical references.
⚠️ Safety disclaimer. Solar inverters carry lethal DC and AC voltage even when "off". This guide covers external, switch-level steps only. Never open the unit or work on wiring unless qualified. When in doubt, call a licensed installer or electrician.