Domestic Hot Water Flow Sensor Saunier Duval Isofast F35 E

Saunier Duval boilers compatible with reference S5720200

Flow meter with reference S5720200. 33 confirmed compatibilities: ThemaClassic C24E and ThemaClassic C25E.

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. S5720200 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 S5720200. 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 flow meter S5720200 resolves.

The flow meter detects the passage of water to activate the domestic hot water. These are the typical symptoms and what to do:

Common symptoms and faults

• 01

  The domestic hot water does not heat even though the burner operates normally in heating.

  Cause: The flow sensor does not detect the passage of water through the DHW circuit, and the boiler does not switch to that mode.

  Check if there is a three-way valve or another element blocking the circuit before assuming it is the flow meter.

• 02

  The boiler does not recognize the flow demand and does not start the DHW mode when the tap is opened.

  Cause: Without flow signal from the sensor, the control board understands that there is no consumption and keeps the burner off.

  Open the tap to maximum flow for a few seconds: if it starts with high flow, the problem may be with minimum pressure, not with the sensor.

• 03

  The temperature of the domestic hot water is irregular or intermittent, rising and falling on its own.

  Cause: The component combines flow and NTC sensor functions; an unstable reading from either one causes the burner response to fluctuate.

  Note if the problem occurs with the same faucet every time or with all of them: if it's just one, check that faucet or its installation first.

• 04

  The fault warning appears only sometimes, and at other times the hot water works normally.

  Cause: A sensor with a degraded contact may provide a correct signal on some starts and fail on others, without a clear pattern.

  Keep a record of when it fails (time of day, flow rate used) to see if the pattern points to the sensor before replacing 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.

Data sheet for the Saunier Duval S5720200 flow meter

Catalogue reference

S5720200

Brand

Saunier Duval

Type of part

Flow detectors

Units in stock

5 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.

Type of component

Domestic hot water flow sensor, thermistor type (NTC), male thread 18 mm + female 28 mm

Flank code (line 1)

00001035190000

Flank code (line 2)

18506224200310

Manuals and technical documentation

Official documentation of the boiler, useful for locating the part and cross-referencing the fault codes.

• Saunier Duval Thematek S F24E Manual (PDF)Document © Saunier Duval, provided as a technical reference.