ATAG fault code 201
Fault code 201 on an ATAG boiler (including I-series) means: Domestic hot water sensor defective (Combi). Reset the appliance once. If the code comes back, a part is usually faulty, often a temperature sensor. You can check the water pressure and settings yourself; leave work on gas-carrying parts to a certified gas engineer.
After a safety alert (gas, flue gas, combustion), reset no more than once and call in a certified gas engineer. If you smell gas, call your national gas emergency number or 112 immediately.
Cause
Fault code 201 on an ATAG boiler indicates: Domestic hot water sensor defective (Combi).
Fixing fault code 201: step by step
- Reset the appliance once; a one-off measuring error will then clear.
- Where you can reach it without opening the sealed combustion section, check that the sensor plug is seated firmly and the wiring is undamaged.
- If the code comes back, the sensor or its wiring is usually faulty (short or open circuit). Sensors in the sealed combustion section should be replaced by a qualified heating engineer.
Applies to
ATAG I-series, i28CZ iCon1, i28ECZ iCon1, i32SZ iCon2, i36CZ iCon2, i36ECZ iCon2.
Click a model for the parts list and exploded view of that appliance.
Fault code 201 on other ATAG series
The same code does not mean the same thing on every series. Check the rating plate to see which series you have:
- 201 on P-series, P20C iCon1, P20EC iCon1, P27C iCon1, P27EC iCon1, P35C iCon2: Domestic hot water sensor fault (e.g. open, short-circuited, out of range).
Matching parts
ATAG parts are available from Instalpunt; shipping to EU countries from €12.95 (€16.95 for more distant countries), usually 3–5 working days.
Parts per Atag-series: A Series · i Series (iCon) · Q Series · E Series · P-series (iCon) · Blauwe Engel · XL-series.
Based on the cause, these original ATAG parts fit (always check the type number of your appliance):
- Atag connector tw ntc4 salmon red S4920900 € 38.05
- Atag NTC return 10K € 40.77
- Atag NTC flow 10k icon € 57.08
Further reading on this cause
Other ATAG codes with the same cause
- 10 — Outdoor sensor fault (e.g. open, short-circuited, out of range)
- 102 — Pressure sensor defective
- 110 — Flow sensor fault (e.g. open, short-circuited, out of range)
- 112 — Return sensor fault (e.g. open, short-circuited, out of range)
- 114 — Outdoor sensor fault (e.g. open, short-circuited, out of range)
- 20 — Flow temperature sensor defective
Fix it yourself or call an engineer?
Always consult the manual for your appliance and work safely. If in doubt or if the fault comes back, call in a qualified professional. A question about a part? Write to us at info@instalpunt.nl.
Frequently asked questions
What does ATAG boiler fault code 201 mean?
Domestic hot water sensor defective (Combi).
How do I fix fault code 201 on an ATAG boiler?
First check the cause described above. Then restart the appliance using the reset button. If the message comes back, a part usually needs replacing or the fault needs to be repaired by a qualified professional.
Which parts do I need for ATAG fault code 201?
That depends on the exact cause. In the ATAG parts overview at Instalpunt you will find the current price and stock for each part.
Can I fix fault code 201 myself?
You can reset the appliance and check things like the water pressure or settings yourself. Work on gas-carrying parts must be left to a certified gas engineer.
All ATAG boiler faults and codes at a glance →