Saunier Duval Isofast F 35 E1 Control Board Display Ref. 05721000
Refurbished Saunier Duval PCBs (control boards)

Saunier Duval Isofast F 35 E1 Control Board Display Ref. 05721000

In the Saunier Duval Isofast boilers, the Isofast F 35 E1 control panel is a PCB that manages the ignition, burner modulation, pump, and safety features of the unit. When it fails, you may notice that the boiler does not start, locks out, or exhibits erratic behavior. This part is compatible with models such as C 28 E, C 35 E, and F 28 E, among others. A technician must confirm through diagnosis whether it needs to be replaced if you experience these symptoms to restore the proper functioning of your boiler.

Type of part
PCBs (control boards)
Status
Refurbished
Catalogue reference
05721000
Warranty
1 year
VAT included Stock · 5 units
Compatibility

Saunier Duval boilers compatible with reference 05721000

PCB with reference 05721000. 14 verified compatibilities: C 28 E and C 28 E1.

Verified compatibility

Boiler modelFamilyVerification
Saunier Duval C 28 EIsofastVerified
Saunier Duval C 28 E1IsofastVerified
Saunier Duval C 28 E NOxIsofastVerified
Saunier Duval C 28 E1 NOxIsofastVerified
Saunier Duval C 35 EIsofastVerified
Saunier Duval C 35 E1IsofastVerified
Saunier Duval F 28 EIsofastVerified
Saunier Duval F 28 E1IsofastVerified
Saunier Duval F 35 EIsofastVerified
Saunier Duval F 35 E1IsofastVerified
Saunier Duval C 28 EIsomaxVerified
Saunier Duval C 28 E2IsomaxVerified
Saunier Duval F 28 EIsomaxVerified
Saunier Duval F 28 E2IsomaxVerified

Can't see your model or have questions? The printed reference takes precedence. How to check it ·

Guide

How to check if ref. 05721000 is the part for your boiler

The part reference, model, and equipment revision must be verified against the manufacturer's documentation.

  1. Find the reference printed on the installed part and check whether it matches the catalogue reference 05721000. 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.
Diagnosis and fault codes

Symptoms that require diagnosis on the PCB 05721000

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

    The screen is off and there are no lights on the remote.

    Cause: The display and control module is not receiving power or signal through the flat cable, even though the boiler is functioning.

    Check that the 8-way flat cable is properly connected, with no bent or oxidized pins.

  • 02

    It does not respond when pressing buttons, nor does it change the temperature or turn on any lights.

    Cause: The keyboard contacts may be worn or damp, preventing the transmission of the keystroke.

    Check if the boiler is still heating with the current configuration; if it heats, the fault is in the control and not in the PCB.

  • 03

    The screen flickers, appears partially, or shows incomplete segments.

    Cause: A poor connection in the flat cable or in the connections of the PCB causes the signal to be intermittent.

    Disconnect and reconnect the flat cable with the boiler turned off, and check if the blinking changes when you slightly move the connector.

Fault codes Saunier Duval that require diagnosis

CodeFaultTechnical checks
F12No signal from the user interfaceYes — it points to this display/interface module or its connection cable with the main PCB.
F18User interface faultYes — it corresponds to this display/control board module.
F13Main PCB faultNo — that code is for the MAIN PCB (a different part), not for this display.

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 data

Data sheet for the Saunier Duval 05721000 PCB.

Catalogue reference
05721000
Uniclima internal SKU
DIF35E1
Brand
Saunier Duval
Type of part
PCBs (control boards)
Units in stock
5 units
Status
Refurbished
Warranty
1 year
Shipping
Delivery time shown at checkout
Return
14 days
Documentation

Manuals and technical documentation

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

Frequently asked questions

Frequently asked questions about the PCB 05721000

Does this display module fit an Isofast C35E1?
Yes, the Isofast C35E1 is on the list of compatible boilers, along with the rest of the Isofast range and Isomax C28E, C28E2, and F28E.
What connector does this module use to connect to the main PCB of the Isofast?
A flat cable that goes to an 8-pin connector.
When should this display module be replaced in the Isofast F35 E1?
The technical diagnosis must confirm that it is necessary to replace it, even when the display does not turn on or does not show any information.
Does this module also work for an Isomax F28E?
Yes, the Isomax F28E is among the compatible boilers listed in this document.

Spare parts related to Saunier Duval Isofast

More spare parts for Saunier Duval Isofast F 35 E1

Delivery calculated by destination Delivery time shown at checkout
1-year warranty inspected and tested
14-day return uninstalled parts
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Saunier Duval Isofast F 35 E1 Control Board Display Ref. 05721000