Junkers Cerastar Gas Valve ZWN24-7MFA23 SIT Ref. 8747003700

Junkers boilers compatible with reference 8747003700

Gas valve with reference 8747003700. 31 verified compatibilities: ZWC 24/28-1 MFA and ZWC 24/28-1 MFK.

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. 8747003700 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 8747003700. If it is not visible, do not identify the part by 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 gas valve 8747003700 resolves.

The gas valve regulates and modulates the gas flow to the burner. These are the typical symptoms and what to do:

Common symptoms and faults

• 01

  The boiler tries to ignite, a clicking sound is heard, but the flame does not appear.

  Cause: One of the two solenoid valves (EV1 or EV2) is not opening correctly and gas is not reaching the burner.

  Measure with a multimeter that both coils receive 24V~ at the moment of ignition before replacing the entire gas valve.

• 02

  The boiler keeps locking out and needs to be reset every few cycles.

  Cause: An intermittent fault in the opening of the gas valve causes the control board not to detect a stable flame and to shut down for safety.

  Check if the lock always coincides with the cold start; if so, first check the condition of the ionization electrode.

• 03

  The gas consumption seems higher than normal for the same feeling of warmth.

  Cause: If the gas valve does not close completely between cycles, it allows some extra gas to pass through even if there is no obvious leak.

  Compare the consumption with previous bills and rule out other causes (insulation, thermostat) before attributing it to the gas valve.

• 04

  When measuring with a multimeter, the current in the coil does not reach the expected values.

  Cause: A damaged coil inside EV1 or EV2 does not generate the necessary force to open the gas flow.

  Before changing the gas valve, check that the connector is not oxidized and that the wire is not frayed, as this can also result in low current readings.

Fault codes from Junkers that this part resolves.

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 gas valve Junkers 8747003700

Catalogue reference

8747003700

Brand

Junkers

Type of part

Gas valves

Units in stock

0 units

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.

Model

845 Sigma

Code printed on the part

0063AS4831

Maximum inlet pressure

60 mbar

EV1 coil

24 V~

Maximum current

165 mA

Working ambient temperature

-15 °C to 60 °C

Batch and manufacturing date

Date 11/23, batch 3114629, no. 2197