Flow Detector (Flow Meter) Glow-worm 25C/30C/35C - Ref. 0020197555

Hermann boilers compatible with reference 0020197555

Flow meter with reference 0020197555. 12 verified compatibilities: Micraplus Condens 25-A and Micraplus Condens 30-A.

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. 0020197555 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 0020197555. 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 0020197555 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 comes and goes suddenly, as if it cuts off and returns every few seconds.

  Cause: The detector's turbine gets stuck with lime and transmits an intermittent flow signal.

  Open and close the tap with a strong flow a couple of times; if the turbine frees up and the cut-off disappears, don't change the part yet.

• 02

  When requesting hot water, the boiler displays a fault code related to the flow instead of igniting.

  Cause: The turbine does not spin enough to provide the minimum signal that the control unit needs to recognize demand.

  Check the water inlet filter first: if it is clogged, it reduces the flow rate and triggers the same warning.

• 03

  In heating mode, the boiler works fine, but when opening any hot water tap, the burner does not start.

  Cause: Without the signal from the flow detector, the PCB cannot detect a demand for domestic hot water.

  Turn the tap fully open for several seconds in a row; if it still doesn't start with maximum flow, the detector is the first suspect.

• 04

  The boiler turns on in domestic hot water mode without any tap being open.

  Cause: The detector keeps indicating flow even though there is no actual water passage, due to wear on the turbine or the magnet.

  Close all the domestic hot water taps in the house and check if the startup persists 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.

Hermann 0020197555 flow meter datasheet

Catalogue reference

0020197555

Brand

Hermann

Type of part

Flow Detectors

Units in stock

1 unit

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.

Body

Black

Connector

White, 3 tabs (contacts)