Viessmann fault code 48
Fault code 48 on a Viessmann boiler (including Vitocrossal 200 and Vitocrossal CIB) means: Open circuit of flow temperature sensor of heating circuit 2 (with mixing valve). 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 48 on a Viessmann boiler indicates: Open circuit of flow temperature sensor of heating circuit 2 (with mixing valve).
Applies to
Viessmann Vitocrossal 200, Vitocrossal CIB, Vitodens 200-W, Vitodens 300-W, Vitodens 333, Vitodens 343-F, -.
Click a model for the parts list and exploded view of that appliance.
Matching parts
Viessmann parts are available from Instalpunt; shipping to EU countries from €17.95 (€24.95 for more distant countries), usually 3–5 working days.
For fault code 48, the part involved is usually in the category: sensor.
Based on the cause, these original Viessmann parts fit (always check the type number of your appliance):
- Viessmann temperature sensor € 57.95
- Viessmann flow sensor WB1b € 107.95
- Viessmann temperature sensor ntc € 88.95
Further reading on this cause
Other Viessmann codes with the same cause
- 10 — Short circuit of outdoor temperature sensor
- 13 — Open circuit of outdoor temperature sensor
- 14 — Short circuit of outdoor temperature sensor
- 18 — Open circuit of outdoor temperature sensor
- 182 — Short circuit of outlet temperature sensor (if present)
- 183 — Open circuit of outlet temperature sensor (if present)
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 Viessmann boiler fault code 48 mean?
Open circuit of flow temperature sensor of heating circuit 2 (with mixing valve).
How do I fix fault code 48 on a Viessmann 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 Viessmann fault code 48?
That depends on the exact cause. In the Viessmann parts overview at Instalpunt you will find the current price and stock for each part.
Can I fix fault code 48 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 Viessmann boiler faults and codes at a glance →