Analog PCB Junkers 8 748 300 091 0 · ZWR24-2 Y Mini 8/11 AE
Analog PCB associated with the control box of Bosch MINI-8K31. Its identification as the main board of this variant is pending confirmation.
- Type of part
- PCBs (control boards)
- Status
- Refurbished
- Catalogue reference
- 8 748 300 091 0
- Warranty
- 1 year
VAT included Stock · 1 unit
Boilers Junkers (Bosch) compatible with reference 8 748 300 091 0
PCB with reference 8 748 300 091 0. A verified compatibility: Junkers MINI-8AE and MINI-11AE (series 21, 23, and 31). There are 6 other models that we are still verifying.
Proven compatibility
| Boiler model | Family | Verification |
|---|---|---|
| Junkers (Bosch) Junkers MINI-8AE and MINI-11AE (series 21, 23, and 31) | Junkers (Bosch) | Contrasted |
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 (Bosch) Junkers MINI-8K and MINI-11K (series 21, 23, and 31) | Junkers (Bosch) | Unconfirmed |
|---|---|---|
| Junkers (Bosch) Junkers MINI-8KE and MINI-11KE (series 21, 23, and 31) | Junkers (Bosch) | Unconfirmed |
| Junkers (Bosch) Junkers MINI-8KSE and MINI-11KSE (series 21, 23, and 31) | Junkers (Bosch) | Unconfirmed |
| Junkers (Bosch) Junkers MINI-8ASE and MINI-11ASE (series 21, 23, and 31) | Junkers (Bosch) | Unconfirmed |
| Junkers (Bosch) Junkers ZSR/ZWR 18, 24-5 KE/AE, ZSR 7/11-5 AE and ZSR 5/11 KE | Junkers (Bosch) | Unconfirmed |
| Junkers ZWR24-2 | Junkers (Bosch) | Unconfirmed |
Can't see your model or have questions? The printed reference takes precedence. How to check it · Send us a photo via WhatsApp.
How to check if reference 8 748 300 091 0 is the part for your boiler
The part reference, model, and equipment revision must be verified against the manufacturer's documentation.
- Locate the markings 8 748 300 091 and 8 748 300 090 on the PCB and copy them exactly as they are.
- Compare them with those on your PCB and with the Bosch reference 8 748 300 091 0 ("Leiterplatte analog").
- Do not confuse it with the 8 748 300 036 0 (another PCB) or with the 8 748 300 143 0 and 144 0 (another Bosch list).
- Note the model and suffix of your boiler on its rating plate: Bosch lists differentiate plates according to the generation.
- If they match, call us at 911 17 77 77 with the model of your boiler.
Symptoms that require diagnosis on the PCB 8 748 300 091 0
The PCB controls the ignition, modulation, and safety features of the boiler. These are the typical symptoms and what to do:
Common symptoms and faults
- 01
B1 appears on the screen and the boiler does not detect the encoder connector.
Cause: Faulty or improperly inserted encoder connector; sometimes, fault in the electronic circuit.
Check that the encoder connector is properly mounted. If the code returns, have a technician measure or replace it.
- 02
E2 appears on the screen and the boiler detects a fault in the NTC sensor.
Cause: NTC sensor interrupted or short-circuited, or defective connection cable.
Check the NTC sensor and its connection cable. If the fault code returns, have a technician check it.
- 03
The boiler tries to ignite and locks out; there is no flame.
Cause: Gas supply issue during ignition or faulty ionization electrode.
Check that the gas valve is open and reset once. If it blocks again, have a technician check it.
Junkers (Bosch) fault codes that require diagnosis
| Code | Fault | Technical checks |
|---|---|---|
| EA | Flame not detected on ignition; the boiler locks out. | Check that gas is reaching and reset once. If it blocks again, have a technician check it: it could be the ionization electrode. |
| B1 | The encoder connector on the PCB is not detected. | Check that the encoder connector is properly mounted. If the code returns, have a technician measure or replace it. |
| E2 | Faulty NTC temperature sensor (inlet sensor). | Check the sensor and its cable. If the fault code returns with the cable in good condition, 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 sheet: Junkers (Bosch) PCB 8 748 300 091 0
- Catalogue reference
- 8 748 300 091 0
- Uniclima internal SKU
- PLC262
- Brand
- Junkers (Bosch)
- Type of part
- PCBs (control boards)
- 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.
- Manufacturer reference
- 8 748 300 091 0 (Bosch ETK: analog PCB for mini-11K and mini-8K)
- Type of component in OEM catalog
- analog PCB
- Additional PCB marking
- 8 748 300 090 (without OEM cross-reference or confirmed equivalence)
- Fuse designator transcribed
- F1A; it is a designation, it does not by itself indicate a rating of 1 A.
- Marked code
- 1.3 (undefined meaning)
- Fuse in BOM mini-8K/mini-11K
- F1,0A · order 1 904 525 003 0; the catalog lists it separately and does not account for the fuse mounted in this unit.
- Voltage, firmware, and revision
- Not identified with the documentation available for this unit.
- Official Bosch catalog (8 748 300 091 0) — Description
- Analog PCB · Analog board · Official Bosch catalog
- Official Bosch catalog (8 748 300 091 0) — Distribution weight
- 0.379 kg · Official Bosch catalog
- compatibility — Junkers
- ZWR24-2 · Compatibility validated in the inventory; check the suffix and revision of the appliance.
- compatibility — Junkers
- The Bosch list 7181465043 associates the number 8 748 300 091 0 with the analog PCB of this family; confirm complete code.
- compatibility — Junkers
- The Bosch list 7181465043 associates the number 8 748 300 091 0 with the analog PCB of this family; confirm complete code.
- Technical sheet: Manufacturer reference
- 8 748 300 091 0 (Bosch ETK: analog PCB for mini-11K and mini-8K)
- Technical sheet: Type of component in OEM catalog
- analog PCB
- Technical sheet: Additional PCB marking
- 8 748 300 090 (without OEM cross-reference or confirmed equivalence)
- Designator of the fuse transcribed
- F1A; it is a designation, it does not by itself indicate a rating of 1 A.
- Technical sheet: Marked code
- 1.3 (undefined meaning)
- Fusible en BOM mini-8K/mini-11K
- F1,0A · order 1 904 525 003 0; the catalog lists it separately and does not account for the fuse mounted in this unit.
- Technical sheet: Voltage, firmware and revision
- Not identified with the documentation available for this unit.
- References — 8 748 300 091 0
- Bosch order number for analog PCB in BOM mini-8K/mini-11K; matches the marking 8 748 300 091 transcribed.
- References — 8 748 300 090
- Second marking of PCB; no Bosch sheet or official replacement chain with 091 was found.
- References — 8 748 300 036 0 / 8 718 300 072 0
- References that appear in the connection box of the Bosch list from the ZR/ZWR -2K family; they do not equate to 091/090.
- References — 8 748 300 143 0 / 8 748 300 144 0
- References from another Bosch list for ZR/ZWR -2 K.E; separate variants, not proven substitutions of 091/090.
- Registered reference
- PCB markings: 8 748 300 091; 8 748 300 090
- Additional markings
- Two physical silkscreens on PCB: 8 748 300 091 and 8 748 300 090; both are retained. Designator F1A (does not confirm 1 A rating by itself). Marked code: 1.3.
- Pending applications to verify
- Junkers ZWR24-2 — declared application in the bag; pending confirmation for the exact variant.
Before purchasing
- To confirm: Junkers MINI-8K and MINI-11K (series 21, 23, and 31) — 1 origin: Bosch (MINI-8K21, 8K23, 8K31, 11K21, 11K23, and 11K31). They only say "mini".
- To confirm: Junkers MINI-8KE and MINI-11KE (series 21, 23, and 31): official sheet from Bosch + (AE and KE)
- To confirm: Junkers MINI-8KSE and MINI-11KSE (series 21, 23, and 31): official sheet from Bosch
- To confirm: Junkers MINI-8ASE and MINI-11ASE (series 21, 23, and 31): official sheet from Bosch
- To confirm: Junkers ZSR/ZWR 18, 24-5 KE/AE, ZSR 7/11-5 AE and ZSR 5/11 KE — Not confirmed for the 091 0. it gives you the 8 748 300 346 0; Bosch (usage note 1: "ZR/ZSR/ZWR...") and specifically ("ZR, ZSR, ZWR") only mention the family: unresolved.
- Do not confuse: 8 748 300 036 0 — PCB "Leiterplatte MC": Bosch lists it alongside 091 0 in position 30 of the MINI-8K31 and alone in the ZWR24-2KD21 — It is another PCB: Bosch states it is constructed the same as 87483000500, not as 091 0.
- Do not confuse: 8 748 300 143 0 / 144 0 — Plates from another Bosch list (ZR/ZWR -2 K.E) — Separate variants; they are not proven replacements for 091/090.
- Do not confuse: 8 748 300 346 0 — Junkers PCB for ZSR/ZWR 18, 24-5 KE/AE, ZSR 7/11-5 AE and ZSR 5/11 KE — it is only associated with those boilers, not with 091 or 090.
- To confirm: note the 090 as the second marking of the PCB and it has not confirmed its crossover with the 091 0. Bosch lists it as the previous code. Individuals and (Warmwasserkönig) offer the 091 and the 090 together.
- To confirm: Identity verified by Bosch, Warmwasserkönig, and Romanian. The ZWR24-2 confirms it; the official breakdown of the ZWR24-2KD21 lists 036 0, not 091 0. Mini-8K and mini-11K: only Bosch.
- Pending confirmation of registered applications by model, variant, or programming: Junkers ZWR24-2.
Frequently asked questions: PCB 8 748 300 091 0
Where is the code for this PCB and which one should I compare?
On the PCB, the markings 8 748 300 091 and 8 748 300 090 are listed: compare them with those on your PCB. Bosch requests it as 8 748 300 091 0 ("Leiterplatte analog", item 30 of the MINI-8K31 parts list) and lists the 090 as the previous code.
Is it compatible with my Junkers ZWR24-2?
Check the status of each model in the compatibility sections; the pending variants are not validated. To confirm: Yes: registered: for the ZWR24-2. It states "für ZWR Serie 2 und mini mit CE425" and provides the 090 taken from a ZWR 24-2KDR23. Note: the Bosch models for the 091 0 are all MINI (its usage note 1 refers to the family "ZR/ZSR/ZWR...") and the parts list for the ZWR24-2KD21 lists the 036 0 in its control box, not the 091 0. Check the suffix of your unit or call us at 911 17 77 77.
Is it compatible with the Junkers mini-8K or the mini-11K?
Check the status of each model in the compatibility sections; the pending variants are not validated. Only Bosch connects it with the mini-8K and mini-11K (1 origin): it remains to be confirmed. Their catalog lists the "Leiterplatte analog" 8 748 300 091 0 in position 30 of the breakdown for the MINI-8K31 and includes it in 36 MINI-8 and MINI-11 models, such as MINI-8K21, 8K23, and 11K31. Compare the marking on your PCB with the 8 748 300 091 or send us a photo of its label and the boiler's PCB from Contact (911 17 77 77).
What is the difference between 8 748 300 091 0 and 8 748 300 090?
Bosch lists it as the previous code ("Ersatzteilvorgänger 1") of the 091 0, with 8715555185 as the second one. Without confirming that crossover. Individuals and (Warmwasserkönig) offer both the 091 and the 090 together, and this PCB has both markings printed on it. Bosch marks the 091 0 as unavailable.
Are the 8 748 300 036 0, the 143 0, or the 144 0 equivalent?
It is not stated that the 143 0 or the 144 0 are equivalent: they appear on another Bosch list (ZR/ZWR -2 K.E) as separate variants, without proven substitution. The 036 0 is another PCB: in the MINI-8K31 Bosch lists in the same position 30 the "Leiterplatte MC" 8 748 300 036 0, which is constructed the same as the 87483000500.
Does the "F1A" on the PCB confirm a 1 A fuse?
Not on its own: it is a transcribed designator. The breakdown of the MINI-8K31 separately lists a fuse F1,0A (1 904 525 003 0, pack of 10), but that does not confirm the fuse installed in this unit.
What is the identified manufacturer reference?
8 748 300 091 0. Bosch lists it as an analog PCB for mini-8K and mini-11K.
What does 8 748 300 090 mean?
It is a second marking transcribed on the PCB. No official equivalence or substitution linking it to 8 748 300 091 0 was found.
Is it compatible with Junkers ZWR24-2?
Check the status of each model in the compatibility sections; the pending variants are not validated. That compatibility is validated in the inventory. Since the Bosch lists distinguish several revisions, the complete code of the device must be checked before selecting the PCB.
Is it also listed for mini-8K and mini-11K?
Yes. The Bosch catalog associates order 8 748 300 091 0 with the analog PCB of both families. The additional marking 090 is not explained by that list.
Does F1A confirm a 1 A fuse?
Not by itself. It is transcribed as a designation. The mini BOM includes a fuse F1,0A separately, but that does not confirm the component mounted in this unit or its variant.
Are 8 748 300 036, 072, 143, or 144 equivalents?
It has not been proven. They appear in lists for different families or revisions and are kept separate from the markings 090/091.
Analog PCB Junkers 8 748 300 091 0 · ZWR24-2 Y Mini 8/11 AE