Junkers Control Board 8744501254 · PCB FD189 for ZWA24-1AM23

Application for the exact variant pending confirmation. It is the control PCB of a Junkers boiler. It has a chip with a label (EPROM) and a white module attached.

Type of part: Junkers
Status: Refurbished
internal SKU: PLC220
Warranty: 1 year

VAT included Stock · 1 unit

Compatibility

Compatible Junkers boilers

Junkers. 0 verified compatibilities. There are 2 other models that we are still checking.

Models pending verification

These models are associated with this reference, but we have not finished verifying them yet, so we do not consider them compatibleIf your boiler is one of them, send us a photo of the part you are going to replace and we will verify it before you purchase.

Junkers ZWC24-1MFA	Junkers	Unconfirmed
Junkers ZWA24-1AM23	Junkers	Unconfirmed

Can't see your model or have questions? The printed reference takes precedence. How to check it · Send us a photo via WhatsApp.

Guide

How to check if it is the part for your boiler

The part reference, model, and equipment revision must be verified against the manufacturer's documentation.

Look for the chip (EPROM) label on the PCB: it should say 8 744 501 254 and LF 01.34 FD:188. On the printed circuit board, the code FD 189.
Also compare the 8 746 301 238 from the welding side, the white module coupled 8 774 201 251, and the fuses marked F1 T2A, F2 T1.25A, and F3 T3.15A.
Do not confuse it with the PCBs 8748300561, 8748300488, 8 748 300 496 or with 8 744 501 228: they are different codes.
Check the rating plate to see that your boiler is a Junkers ZWA24-1AM23. If it is another model, compare the codes before ordering it.
if they match, call us at 911 17 77 77 with the model of your boiler.

Diagnosis and fault codes

Symptoms that require diagnosis in the junkers

Common symptoms and faults

01
The boiler does not ignite and shows EA.
Cause: Gas shortage, air in the line, or defective ignition or ionization electrodes. There may also be moisture on the PCB.
Check the gas valve and press reset once. If it appears again, have a technician check it.
02
The boiler displays F0 on the screen.
Cause: Internal fault in the electronics, almost always in the PCB; sometimes it is defective ignition connections or wires.
Check the electrical connections and the ignition wires. If the fault code returns, have a technician check it to replace the PCB.
03
The boiler is not working and the indicators are not lighting up, even though there is a demand for heating.
Cause: F1 or F2 fuse, transformer, faulty electrical connection or printed circuit board.
A technician should check the voltage, the fuses, the transformer, and the PCB.
04
The heating is not working, but hot water is coming out.
Cause: Incorrect signal from the room thermostat, faulty thermostat, or defective PCB.
Have a technician check it, as they need to verify the room thermostat, its connections, and the PCB.

Junkers fault codes that require diagnosis

Code	Fault	Technical checks
E9	Safety temperature limiter activated on the supply.	Check the pressure of the installation, ensure the pump is working and the fuse of the PCB, and bleed the unit. If it happens again, have a technician check it.
d3	The bridge is missing in the safety connector of the PCB (terminals 8-9 open).	Check that the jumper or connector of the thermostat is properly placed according to the diagram. If it is correct and the fault code persists, it points to the PCB; have a technician check it.
E2	NTC sensor of the supply line faulty or disconnected.	Check the flow sensor and its connection cable. If the sensor is fine, point to the PCB; have a technician check it.
EA	No ignition flame detected.	Check that there is gas and press reset once. If it repeats, it points to the ignition or ionization electrodes, or the PCB; have a technician check it.
F0	Internal electronic error (internal fault of the PCB or its connections).	Check the electrical connections and the securing of the ignition wires. If the issue persists, the PCB is usually the part that needs to be replaced; have a technician check it.
E0	Internal fault in the PCB (control board).	Check for any moisture or sulfated contacts on the PCB. If the issue persists, the PCB needs to be replaced; have a technician check it.

These symptoms can have more than one cause. If your boiler displays a fault code, send it to us via WhatsApp along with a photo of the labeling, and we'll tell you if this is the part.

Technical data

Technical sheet: Junkers

Uniclima internal SKU: PLC220
Brand: Junkers
Type of part: Junkers
Units in stock: 1 unit
Status: Refurbished
Warranty: 1 year
Shipping: Delivery time shown at checkout
Return: 14 days

Part data and available documentation

Contrast the label codes, PCB, and revision with the installed part; they are not necessarily equivalent references.

Marked port: SCL;SDA;5V;GND
Marked fuse: T3.15A F3
Inventory — Chip/EPROM label: 8 744 501 254; LF 01.34 FD:188
Inventory — Marked supply: 230 V
Inventory — Fuse F1: T2A
Inventory — Marked subcomponent: 68 nK275~
Inventory — Blue condenser: 0.47 μF; 400 N9
Inventory — Relay/subcomponent: H11-24
Inventory — White coupled module: 8 774 201 251; E 372/6/6
Inventory — Code visible on the welding face/label: 8 746 301 238
Inventory — Application indicated in inventory: ZWA24-1AM23
Identification — Marked code: 8 744 501 254
Identification — Marked code: LF01.34
Identification — Marked code: FD188
Identification — Marked code: FD189
Identification — Marked code: HTIII-2a /BA BB BB
Puerto marcado: SCL;SDA;5V;GND
Technical sheet: Marked fuse: T1.25A F2
Technical sheet: Marked fuse: T3.15A F3
Inventory data — Chip/EPROM label: 8 744 501 254; LF 01.34 FD:188
Inventory data — Marked supply: 230 V
Inventory data — Fuse F1: T2A
Inventory data — Marked subcomponent: 68 nK275~
Inventory data — Blue condenser: 0.47 μF; 400 N9
Inventory data — Relay/subcomponent: H11-24
Inventory data — White coupled module: 8 774 201 251; E 372/6/6
Inventory data — Code visible on the welding face/label: 8 746 301 238
Inventory data — Application indicated in inventory: ZWA24-1AM23
Additional markings: Chip/EPROM label: 8 744 501 254; LF 01.34; FD:188. PCB silkscreen: FD 189. Fuses F1 T2A; F3 T3.15A; F2 T1.25A. Subcomponent marking 68 nK275~. Blue capacitor: 0.47 μF; 400 N9. Relay/subcomponent: H11-24. Coupled white module: 8 774 201 251; E 372/6/6. Code visible on solder joints/label: 8 746 301 238. Port: SCL; SDA; 5V; GND. Marked code HTIII-2a / BA BB BB.
Pending applications to verify: ZWA24-1AM23 — noted compatibility; pending confirmation by variant. Statements from (documentation 23/10/2026; revision 24/10/2026), pending confirmation by manufacturer. Check reference, revision, and serial number before use: Euromaxx ZWC 24-1 MFA · Euromaxx ZWC 28-1 MFA · Euromaxx ZWC 24-1 MFK · Euromaxx ZWC 28-1 MFK

Before purchasing

To confirm: Junkers ZWC24-1MFA: the 8744501254; others provide 8748300506 and 87144111740 for it.
Do not confuse: 8748300561 — PCB (control board) that is a spare part ready for the Junkers ZWA24-1AM23 — It is another code: without additional confirmation read, it links it to 8744501254. It is not stated that they are interchangeable.
Do not confuse: 8748300488 — PCB 288.45.0020 from a distributor (original code 87483004880) that lists the ZWA24-1AM23, the ZWA24-1KM31, and the ZWA24-1AM31 — It is another code: without additional confirmation read, it links to 8744501254.
Do not confuse: 8 748 300 496 — PCB of the Eurosmart ZWA 24-1 A in the official spare parts list 7 181 465 343 — It is from the ZWA 24-1 A variant, not from the AM 23, and it is a different code: without additional confirmation read, it links to 8744501254.
Do not confuse: 8748300506 / 87144111740 — Boards for the Junkers ZWC24-1MFA (the 87144111740 as "encoder") — They are other codes: without additional confirmation read, it links them to 8744501254.
Do not confuse: 8 744 501 228 — Reference visible on the chip of a Junkers ZWA 24 advertised in — It looks similar in the first digits, but it is a different code. It is not listed as the same PCB.
Different ones are provided for the ZWA24-1AM23 with other codes (8748300561, 8748300488). For that boiler, registered confirmation: this one, 8744501254: refer to the code printed on your PCB.
registered. Outside of it, spare parts (ZWC24-1MFA) and (Junkers ZWA) provide the code 8744501254. We have not found an official parts list.
Pending registered applications to confirm by model, variant, or programming: Junkers ZWA24-1AM23.

Frequently Asked Questions

Frequently asked questions: junkers

How do I identify the Junkers 8744501254 PCB?

Look for the code 8 744 501 254 on the chip label (EPROM) with LF 01.34 FD:188, and on the printed circuit board the serigraph FD 189. Also check the 8 746 301 238 on the solder side, the attached white module 8 774 201 251 (E 372/6/6), and the port marked SCL, SDA, 5V, GND.

Is it compatible with my Junkers ZWA24-1AM23?

The compatibility of this variant is pending confirmation. Registered application: this PCB 8744501254 for the ZWA24-1AM23. We have not found an official parts list that mentions the code. Outside, it gives 8744501254 for a Junkers ZWA, without the complete model. Always compare the code printed on your PCB.

Is it compatible with the Junkers ZWC24-1MFA?

The compatibility of this variant is pending confirmation. The spare part code 8744501254 is listed for the ZWC24-1MFA (only the title of the technical sheet was read), but there are other PCBs for that boiler: 8748300506 and 87144111740 (encoder). If your boiler is that one, compare 8 744 501 254 on the chip and FD 189 on the circuit, and send us a photo of the label from Contact or call 911 17 77 77.

Is the 8748300561 board the same as the 8748300488 or the 8 744 501 228?

We do not know: without additional confirmation, it links them to 8744501254, so we do not consider them equivalent. The 8748300561 for the ZWA24-1AM23 and a distributor the 8748300488 (original code 87483004880). It gives you 8 744 501 228 on the chip of a ZWA 24. For the ZWA24-1AM23, confirmation registered: the 8744501254: compare the complete code of your PCB.

What do the codes 8 744 501 254, FD 189, and LF 01.34 mean?

8 744 501 254 is the chip label code and the main code of the part. FD 189 is the code printed on the PCB and LF 01.34 FD:188 is the rest of the marking on the chip label: the FD:188 of the chip is not the FD 189 of the PCB. We have taken them from the part marking: we have not found manufacturer documentation explaining each code.

Is the code 8744501254 required?

To confirm: Yes, outside: of spare parts (technical sheet of the ZWC24-1MFA), in Italy, titled "Boiler sheet Junkers ZWA 8744501254". None provide the complete model ZWA24-1AM23 or technical data of the PCB. These are 2 of the ones we requested to verify the code outside the workshop.

Who should install this PCB?

A qualified technician: the PCB is marked 230 V. Before replacing it, check the marked fuses: F1 T2A, F2 T1.25A, and F3 T3.15A.

Entrega calculada por destino Delivery time shown at checkout

1-year warranty reviewed and tested

14-day return uninstalled parts

Technical support we verify your model

Junkers Control Board 8744501254 · PCB FD189 for ZWA24-1AM23