3-Way Valve For Boilers ZW20 And ZW23 - Ref. 8708505014

Junkers boilers compatible with reference 8708505014

Three-way valve with reference 8708505014. 12 verified compatibilities: ZW20-1AME and ZW20-1KD.

Proven compatibility

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. 8708505014 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.

1. Find the reference printed on the installed part and check whether it matches the catalogue reference 8708505014. If it is not visible, do not identify the part from its shape alone.
2. Check the full boiler model on its data plate and look for it in the model associations on this page.
3. Compare the connections and physical body with the original part before installation.
4. 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 8708505014 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

  When opening a hot water tap, the radiators suddenly become cold, but the water takes time to arrive or comes out lukewarm.

  Cause: The internal shutter does not fully move to the hot water side, so the water is distributed between the two circuits instead of going to just one.

  Check that the actuator makes a 'click' at the end of its travel when you open the tap; if it doesn't reach the stop, the gas valve is not switching properly.

• 02

  With the heating on, when opening the hot water tap, the radiators remain hot instead of losing priority.

  Cause: If the shutter gets stuck halfway, it does not allow the full flow to the domestic hot water circuit, and it loses the priority it should have.

  Check that the thermostat or the domestic hot water sensor is not giving an incorrect value before assuming that the fault is mechanical in the gas valve.

• 03

  There is a continuous buzzing sound in the valve, as if the motor is straining without actually moving.

  Cause: The solenoid or integrated motor attempts to move the shutter, but it is jammed due to lime scale or a worn return spring, and the motor continues to exert force.

  With the boiler disconnected, if accessible, try to move the stem by hand; if it's stiff or doesn't return to its position on its own, confirm the seizing.

• 04

  Water is leaking or there is moisture between the two fittings of the valve, in the central area.

  Cause: A deteriorated internal O-ring allows the two circuits to mix or leak through the valve body.

  Dry the area well and check again after a complete cycle of heating and domestic hot water to confirm that the leak is coming from that point and not from a poorly tightened fitting.

• 05

  The domestic hot water comes out intermittently, hot and then cold, without any apparent reason.

  Cause: If the shutter oscillates between positions instead of staying fixed on the hot water side, the flow is intermittently distributed between the two circuits.

  Note if the cut coincides with the burner start; if so, check the domestic hot water sensor and the PCB before considering the gas valve faulty.

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 8708505014 three-way valve.

Catalogue reference

8708505014

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