
Saunier Duval Isofast F 28 E DHW Micro Accumulator Ref. 05720400
The Saunier Duval Isofast F 28 E ACS micro-accumulator is a small tank that keeps hot water ready, reducing the waiting time when turning on the tap. If it fails, you will notice that the wait for hot water increases and the water temperature may fluctuate. This model is compatible with several boilers from the Isofast range, such as the C 28 E, C 28 E1, F 28 E1, among others. It is recommended to replace it when you start experiencing these hot water supply issues.
VAT included
Consult via WhatsAppSaunier Duval boilers compatible with reference 05720400
Grupo hidráulico con referencia 05720400. Diez compatibilidades contrastadas: C 28 E y C 28 E1.
Proven compatibility
| Boiler model | Family | Verification |
|---|---|---|
| Saunier Duval C 28 E | Isofast | Contrasted |
| Saunier Duval C 28 E1 | Isofast | Contrasted |
| Saunier Duval C 35 E | Isofast | Contrasted |
| Saunier Duval C 35 E1 | Isofast | Contrasted |
| Saunier Duval F 28 E | Isofast | Contrasted |
| Saunier Duval F 28 E1 | Isofast | Contrasted |
| Saunier Duval F 35 E | Isofast | Contrasted |
| Saunier Duval F 35 E1 | Isofast | Contrasted |
| Saunier Duval 120 COMBI NG | XTRAFAST | Contrasted |
| Saunier Duval 96 COMBI NG | XTRAFAST | 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 the ref. 05720400 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 05720400. 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.
Síntomas y errores que soluciona el grupo hidráulico 05720400
The hydraulic group includes the valve, the by-pass, and the water connections. These are the typical symptoms and what to do:
Common symptoms and faults
- 01
The hot water takes time to come out or comes out cold for a moment before heating up, as if there is a cold stream halfway.
Cause: The micro-accumulator no longer retains the hot water that it should deliver instantly, so that quick start effect is lost.
Check that the boiler maintains the reserve temperature well and that there are no pressure losses before declaring the component faulty.
- 02
Warm water comes out when the domestic hot water tap is open, even though the boiler seems to be functioning normally.
Cause: If the micro-accumulator loses tightness or becomes filled with scale, it no longer accumulates or transfers the heat it is supposed to.
Check for visible leaks around the fittings of the micro-accumulator before replacing it.
- 03
There is a leak or moisture near the area where the micro-accumulator is installed.
Cause: The tank or its connections have lost tightness and are slowly leaking water.
Locate the exact source of the moisture and rule out the joints of the nearby fittings first.
- 04
The domestic hot water temperature varies during use, rising and falling for no apparent reason.
Cause: A micro-accumulator that does not retain water well causes the boiler to compensate with modulation changes that are noticeable at the tap.
Check the circuit pressure and the condition of the inlet filter before replacing the part.
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.
Ficha del grupo hidráulico Saunier Duval 05720400
- Catalogue reference
- 05720400
- Brand
- Saunier Duval
- Type of part
- Hydraulics
- Units in stock
- 4 units
- Status
- Refurbished
- Warranty
- 1 year
- Shipping
- 1-2 business days
- Return
- 14 days












