What It Means
- NTC domestic hot water sensor faulty.
Lennox Hydronic Heating
Lennox Error Code 321
Hydronic Heating:
Causes & actions from Lennox
How it shows
- boiler control fault display: 321
Call authorized SERVICE technician
Applicable models & manual sources
- GCWB95W-150
NTC domestic hot water sensor faulty.
GCWB95W-150, GCWB95W-205, GCWB95F-150
Disclaimer: This information is for general reference. Code wording and instructions vary by model. Always follow the service manual for your exact unit.
What should you check next?
Continue in ACLogics with guided diagnosis for your equipment and symptoms.
