Felicity Inverter Error Codes: Complete Guide for All Models

Your Felicity inverter has stopped, the red LED is on, and a number is sitting on the screen. Before you do anything else, look at that LED. Solid red with the output cut off means a fault — the inverter has shut its output down to protect itself, and the buzzer sounds continuously. Flashing red while your appliances keep running means a warning — the unit is still working, but it wants attention, and the buzzer beeps on and off. The same number can appear in both lists on some models, so the LED tells you which table to read. And if your screen says F15 instead of 15: Error 15 and F15 are the same fault — some models and firmware versions simply add the "F".

In a hurry? Type the code on your screen into the Felicity error-code lookup — 1,356 codes across 46 devices, each with the official cause and recommended fix.

How to read the code on your screen

Felicity documents two separate code tables for each inverter: fault codes and warning codes. A fault stops the output — you get a solid red LED, a continuous buzzer, and the code steady on the LCD. A warning leaves the output running — the red LED flashes, the code flashes on the LCD, and the buzzer beeps intermittently. This matters because a number like 14 exists in both tables on the newer IVPS generation: solid 14 is "output voltage high" (a fault), while flashing 14 is "input phase abnormal" (a warning). Match the LED state first, then the number.

IVPS and IVPM error codes (official list)

These two tables cover the IVPS/IVPM family — the models most Felicity owners have. The classic generation includes IVPS2512, IVPS2524, IVPS3524, IVPS5024, IVPS5048, IVPS7548, IVPS10048 and the IVPM5048/7548/10048. The newer parallel-capable generation covers IVPS3524P1G1-LV, IVPS5048P1G1-LV, IVPS7548P2G1 and IVPS10048P2G1. Codes 27, 32, 34 and the 40–72 parallel-system faults exist only on the newer P1G1/P2G1 generation; the MPPT warnings 83, 84, 85, 87 and 88 belong to the classic series with a built-in solar charger. Every chip links to that code's full page in the directory.

Warning codes — red LED flashing, the inverter keeps running

Fault codes — red LED solid, output cut off

Seeing 02 or 03? Those numbers are not defined on IVPS/IVPM inverters — on this family, battery low is warning 04 and over-temperature is fault 18. Codes 02 and 03 do exist on other Felicity devices (T-REX inverters, LUX batteries, the SCCM charge controller) with their own meanings — check your model in the directory.

The most-searched Felicity codes, explained

Error 15 / F15 — Output short circuit (IVPS family)

This is a fault: the output cuts off and the red LED stays solid. Per the official IVPS user guide, a short circuit has been detected on the AC output — in the wiring or in a connected appliance.

1. If the utility (AC input) is connected, cut off the AC input first
2. Switch the inverter off
3. Disconnect every AC output wire — no loads left on the output
4. Switch it back on

If the screen still shows 15 with nothing connected, the fault is internal — stop there and contact a technician. If it starts cleanly, the short is in your wiring or one appliance: reconnect circuits one at a time until you find it, and make sure none of the output wiring or loads are short-circuited before putting them back in service.

On other models: T-REX hybrids up to 10 kW and the Apollo ESS use F15 for a failed buck-boost current sensor (a service job), IVEM inverter-chargers use it for abnormal PV power, and on the LUX S-1600 battery, 15 means PV2 voltage too high. The code 15 page lists every device-specific meaning.

Error 34 — Heavy overload or output short (newer IVPS generation)

Defined only on the P1G1/P2G1 generation (IVPS3524P1G1-LV, IVPS5048P1G1-LV, IVPS7548P2G1, IVPS10048P2G1). The output is either heavily overloaded or short-circuited, and the manual says to handle it as fault 13 and fault 15 combined: switch off and reduce the load below the rated output; if 34 returns with a modest load, disconnect all output wiring and test for a short exactly as with error 15 above.

On other models: 34 means heat-sink over-temperature on the T-REX-3KLP1G01, radiator over-temperature on the IVCM1012 PRO, and a grid under-voltage alarm on the IVGM5KL-P1G1 — see the code 34 page.

Error 24 — Output voltage low (IVPS family)

A fault: the inverter's output voltage has dropped below range. Per the official guide: switch the inverter off, disconnect all AC output wiring, and switch it on again. If it still shows 24 with nothing connected, it needs service. If it runs normally, a big load was probably pulling the output down — identify it, disconnect it, and confirm the inverter stays normal.

On other models: 24 is a software-detected overcurrent/surge on the T-REX-3KLP1G01 and excessive inverter current on the IVCM1012 PRO — see the code 24 page.

Error 27 — Battery disconnected (newer IVPS generation)

Only on the P1G1/P2G1 generation. The inverter can no longer see the battery — the connector is loose or disconnected. The official fix is exactly that simple: check the battery connector. Make sure it is fully seated and the connections are tight; if the fault stays with a good connection, contact a technician. The classic IVPS/IVPM series does not define 27.

On other models: on the IVGM5KL-P1G1, 27 is a battery over-current fault — see the code 27 page.

Error 05 — Power derating, low utility voltage (warning)

A warning, not a fault: the red LED flashes and the inverter keeps running at reduced output power. The cause is a low AC input voltage, around 90–170 V. Read the input voltage on the screen: if it really is in that band, this is normal behavior — output derates until the utility recovers. If the input voltage is not low, contact a technician.

On other models: 05 means high charging current on LUX-Y batteries, PV over-current on the IVGM5KL-P1G1, and PV high loss on the SCCM3024-III controller — see the code 05 page.

Error 01 — Overload warning (IVPS family)

Flashing red, still running: the connected load is above the inverter's rated output power. The manual is blunt — the inverter forbids overload, and the remaining working time depends on the load percentage. Reduce the load promptly; if you leave it, the unit escalates to fault 13 and cuts the output.

On other models: 01 means high battery voltage on LUX batteries and PV voltage too high on the T-REX-3KLP1G01 — see the code 01 page.

Error 13 — Overload fault (IVPS family)

Solid red, output cut: the load exceeded the rated output power in battery mode. Switch the inverter off, reduce the load below the rated output, then switch it on again. If the overload happens while the AC input is on, wait about 30 seconds and the fault clears automatically. If 13 keeps returning, measure your actual load — motor appliances such as pumps and air conditioners can surge well above their nameplate figure at startup.

On other models: 13 is a slave-communication failure on LUX-Y batteries — see the code 13 page.

Error 17 — Battery voltage high (IVPS family)

A fault. Per the official guide: read the battery voltage from the screen and measure it at the battery with a multimeter. If both readings are above 60 V (on 48 V models), stop using the battery — it may have a problem. If the two readings disagree, the issue may be on the inverter's measurement side — contact a technician.

On other models: 17 is an overload timeout on the T-REX-3KLP1G01 and an EEPROM fault on the SCCM3024-III — see the code 17 page.

Error 18 — Over temperature (IVPS family)

The inverter has overheated and shut its output down. Switch it off and let it cool; once the temperature is back to normal, it can be used again. To stop it recurring, keep the vents clear, keep the unit out of direct sun, and clean dust from the grilles. Note: generic code lists on the web put over-temperature on 02 — on Felicity IVPS units it is 18.

On other models: 18 is a battery under-voltage alarm on the IVGM5KL-P1G1 — see the code 18 page.

Other Felicity model families

Not an IVPS? Every Felicity product line has its own code table, and the directory keeps one page per device with the full official list:

Look up your exact code

The Felicity error-code directory holds 1,356 codes across 46 devices — every inverter, battery, ESS unit, charge controller and charger above, each code with its official cause and recommended fix. Type the code from your screen (for example 15, 34 or E10) and you go straight to the answer for your model.

📞 Still showing the code after these steps? Message a technician on WhatsApp +971 4 255 0887 — free lifetime support is included with every unit we supply. Prefer to talk? Call us or reach out through the contact page.