3-Way Valve Motor ZWC 28-1 (MF2A / MF2K / MFA) Ref. 8717204345
The 3-way valve Motor 3-Way Valve ZWC 28-1 (MF2A / MF2K / MFA) is responsible for switching the water between the heating circuit and the domestic hot water circuit. If this part fails, you will notice that there is hot water but no heating, or vice versa, and sometimes both circuits may mix. It is compatible with boilers from the Euromaxx ZWC28 range, such as the models ZWC28-1MFA 23, ZWC28-1MFK 23, ZWC28-1MF2A 23, ZWC28-1MF2K 23, among others, as well as some models from the Euromaxx ZWC24 range. You should replace it when you experience these symptoms or if you observe a malfunction in the water distribution.
VAT included
Consult via WhatsAppJunkers boilers compatible with reference 87172043450
Three-way valve with reference 87172043450. Ten confirmed compatibilities: ZWC28-1MFA 23 and ZWC28-1MFK 23.
Proven compatibility
| Boiler model | Family | Verification |
|---|---|---|
| Junkers ZWC28-1MFA 23 | Euromaxx ZWC28 | Contrasted |
| Junkers ZWC28-1MFK 23 | Euromaxx ZWC28 | Contrasted |
| Junkers ZWC28-1MF2A 23 | Euromaxx ZWC28 | Contrasted |
| Junkers ZWC28-1MF2K 23 | Euromaxx ZWC28 | Contrasted |
| Junkers ZWC 28/28-1MFK 23 | Euromaxx ZWC28 | Contrasted |
| Junkers ZWC 28/32-1MFA 23 | Euromaxx ZWC28 | Contrasted |
| Junkers ZWC24-1MFA 23 | Euromaxx ZWC24 | Contrasted |
| Junkers ZWC24-1MFK 23 | Euromaxx ZWC24 | Contrasted |
| Junkers ZWC24-1MF2A 23 | Euromaxx ZWC24 | Contrasted |
| Junkers ZWC 24/28-1MFA 23 | Euromaxx ZWC24 | Contrasted |
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 ref. 87172043450 is the part for your boiler
What determines it is not the boiler model, but the reference printed on the part you already have installed.
- Find the reference printed on the installed part and check whether it matches the catalogue reference 87172043450. If it is not visible, do not identify the part from its shape alone.
- Check the full boiler model on its data plate and look for it in the model associations on this page.
- Compare the connections and physical body with the original part before installation.
- If anything is unclear, send us a photo of the marking via WhatsApp before placing your order.
Symptoms and faults that the 3-way valve 87172043450 resolves.
The 3-way valve diverts water between heating and domestic hot water. These are the typical symptoms and what to do:
Common symptoms and faults
- 01
The boiler only provides domestic hot water and the heating does not start even though the thermostat is calling for temperature.
Cause: The motor has not moved the valve stem to heating, so the water continues only for domestic hot water.
With the boiler cold, check if when requesting heating the motor tries to turn or remains stationary.
- 02
Do you hear a clicking or thumping sound when switching the boiler service?
Cause: The internal gear of the motor is worn and slips before engaging in the final position.
Listen to the noise during several ignition cycles and compare it with the usual sound before deciding to make the change.
- 03
The display shows a fault code related to the three-way valve and the boiler locks out.
Cause: The control board does not receive confirmation of the position change in time.
Reset the boiler and check if the fault repeats at the same point in the cycle before replacing the motor.
- 04
The valve motor is continuously making a sound, as if it's straining, without the boiler changing mode.
Cause: The motor is running but cannot move the valve body, stuck due to limescale or dirt.
With the boiler turned off, try to manually move the valve shaft to rule out mechanical sticking.
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.
Data sheet for the Junkers 87172043450 three-way valve.
- Catalogue reference
- 87172043450
- Brand
- Junkers
- Type of part
- 3-way valves
- Units in stock
- 1 unit
- Status
- Refurbished
- Warranty
- 1 year
- Shipping
- 1-2 business days
- Return
- 14 days
Data read on the part and in the manufacturer's documentation
What we have not been able to verify does not appear here.
- Component code (motor)
- 8717204345
- Voltage
- 24V
- Frequency
- 50Hz
- Thermal class
- T70
- Internal batch code
- 31650003.02
Manuals and technical documentation
Official documentation of the boiler, useful for locating the part and cross-referencing the fault codes.
- Junkers ZWC28-1MFA 23 manual (PDF)Document © Junkers, provided as a technical reference.
Frequently asked questions about the 3-way valve 87172043450
Is the 3-way valve motor ZWC 28-1 (Ref. 87172043450) compatible with a ZWB 24-1 A boiler?
What fault does the valve motor ZWC 28-1 Ref. 87172043450 resolve?
What voltage does the motor of the ZWC 28-1 valve operate at?
Spare parts related to Junkers Euromaxx ZWC28
