Differential Temperature inlet/ outlet high
The 14 error code on Burnham boilers indicates differential temperature inlet/ outlet high.
Burnham 14 means: differential temperature inlet/ outlet high. The usual causes are inadequate boiler water flow. verify that circulation pump is operating and that circulation pump and piping are sized per or section of this manual. You can safely reset the boiler once — if 14 returns, do not keep resetting. A qualified heating engineer should diagnose the root cause.
What Does 14 Mean
The 14 code is shown by the boiler’s control board when it detects differential temperature inlet/ outlet high. The boiler then stops instead of continuing to run in that condition: the code is the appliance reporting a problem, not proof that the boiler is broken.
| What you see on the boiler |
|---|
| The display shows 14 and the boiler stops until the fault is cleared |
Common Causes
Causes documented in the Burnham service literature published by usboiler.net, cross-checked against the manufacturer’s fault-code table.
| Cause |
|---|
| Inadequate boiler water flow. Verify that circulation pump is operating and that circulation pump and piping are sized per |
| Section of this manual |
Safety Warning
14 involves electrical or pressure-related components. Do not attempt repairs without proper qualifications. Ensure the boiler is electrically isolated before any inspection. If you notice water leaks, unusual sounds, or pressure anomalies, contact a qualified heating engineer immediately.
Parts & Prices
Prices shown are indicative. Actual prices and availability vary by region.
Step-by-Step Diagnosis
Consult service manual
Refer to the Burnham service documentation for the specific diagnosis procedure for fault code 14.
Check error log
Access the boiler error log to check for related fault codes that may help identify the root cause.
Contact manufacturer support
If the fault persists after basic checks, contact Burnham technical support for specialist guidance.
How to Fix It
Check the pump is receiving power and turning freely; free a seized shaft or replace the pump if it does not run.
Have this checked: Section of this manual
Refer to the Burnham service documentation for the detailed procedure. Only a qualified engineer should carry out these repairs.
Diagnostic Tools
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Affected Models
Burnham models that can display fault code 14:
| Model Family | Output Range | Frequency |
|---|---|---|
| All Burnham models | — | Possible |
Frequently Asked Questions
14 is not classified as a high-severity fault, so the boiler can be reset once. If 14 comes back, stop resetting: the underlying cause is still there and needs a qualified heating engineer.