E!Error Code Search
Keston · Boilers and HVAC

Legacy Keston Heat 45 and 55 commercial boilers

Product information, applicable models, official documentation and 18 indexed error-code explanations for Legacy Keston Heat 45 and 55 commercial boilers.

Legacy Keston Heat 45 and 55 commercial boilers
18indexed codes
1named models or series
1official links
Product overview

About Legacy Keston Heat 45 and 55 commercial boilers

Legacy Keston Heat 45 and 55 commercial boilers is indexed in the Boilers and HVAC directory for United Kingdom, Ireland and Romania. This page brings the available product context, model references, documentation and diagnostic codes together in one place.

The codes below apply only where the linked code page lists this product or model. Confirm the complete model identifier because manufacturers may reuse the same characters across different ranges, generations and control systems.

An error code describes a condition detected by the product; it does not prove that a named component has failed. Follow the exact manual, avoid repeated resets and use an appropriately qualified technician whenever checks require internal access.

Applicability

Models and series

Heat 45; Heat 55; Heat 45P; Heat 55P
Complete directory

All Legacy Keston Heat 45 and 55 commercial boilers error codes

Showing 1–18 of 18

BCC FAULTKeston · Legacy Keston Heat 45 and 55 commercial boilers · United Kingdom, Ireland and RomaniaBCC FAULT – legacy Keston Heat 45/55 error codeKeston documents “Boiler coding component fault” for the legacy Heat 45, 55, 45P and 55P controller. This is…CYLINDER THERMISTOR FAULTKeston · Legacy Keston Heat 45 and 55 commercial boilers · United Kingdom, Ireland and RomaniaCYLINDER THERMISTOR FAULT – legacy Keston Heat 45/55 error codeKeston documents “Cylinder thermistor fault” for the legacy Heat 45, 55, 45P and 55P controller. This is a…ERROR 20Keston · Legacy Keston Heat 45 and 55 commercial boilers · United Kingdom, Ireland and RomaniaERROR 20 – legacy Keston Heat 45/55 error codeKeston documents “False-flame lockout” for the legacy Heat 45, 55, 45P and 55P controller. This is a distinct…EXTERNAL INTERLOCK OFFKeston · Legacy Keston Heat 45 and 55 commercial boilers · United Kingdom, Ireland and RomaniaEXTERNAL INTERLOCK OFF – legacy Keston Heat 45/55 error codeKeston documents “External safety interlock operated” for the legacy Heat 45, 55, 45P and 55P controller. This is…FAN FAULTKeston · Legacy Keston Heat 45 and 55 commercial boilers · United Kingdom, Ireland and RomaniaFAN FAULT – legacy Keston Heat 45/55 error codeKeston documents “Fan fault” for the legacy Heat 45, 55, 45P and 55P controller. This is a distinct…FLAME LOSSKeston · Legacy Keston Heat 45 and 55 commercial boilers · United Kingdom, Ireland and RomaniaFLAME LOSS – legacy Keston Heat 45/55 error codeKeston documents “Flame loss during operation” for the legacy Heat 45, 55, 45P and 55P controller. This is…FLOW FLUE THERMISTOR FAULTKeston · Legacy Keston Heat 45 and 55 commercial boilers · United Kingdom, Ireland and RomaniaFLOW FLUE THERMISTOR FAULT – legacy Keston Heat 45/55 error codeKeston documents “Flow or flue thermistor fault” for the legacy Heat 45, 55, 45P and 55P controller. This…FLOW RETURN REVERSEDKeston · Legacy Keston Heat 45 and 55 commercial boilers · United Kingdom, Ireland and RomaniaFLOW RETURN REVERSED – legacy Keston Heat 45/55 error codeKeston documents “Flow and return connections reversed” for the legacy Heat 45, 55, 45P and 55P controller. This…FLOW THERMISTOR FAULTKeston · Legacy Keston Heat 45 and 55 commercial boilers · United Kingdom, Ireland and RomaniaFLOW THERMISTOR FAULT – legacy Keston Heat 45/55 error codeKeston documents “Flow thermistor fault” for the legacy Heat 45, 55, 45P and 55P controller. This is a…FLUE THERMISTOR FAULTKeston · Legacy Keston Heat 45 and 55 commercial boilers · United Kingdom, Ireland and RomaniaFLUE THERMISTOR FAULT – legacy Keston Heat 45/55 error codeKeston documents “Flue thermistor fault” for the legacy Heat 45, 55, 45P and 55P controller. This is a…IGNITION LOCKOUTKeston · Legacy Keston Heat 45 and 55 commercial boilers · United Kingdom, Ireland and RomaniaIGNITION LOCKOUT – legacy Keston Heat 45/55 error codeKeston documents “Ignition lockout” for the legacy Heat 45, 55, 45P and 55P controller. This is a distinct…LOW MAINS VOLTAGEKeston · Legacy Keston Heat 45 and 55 commercial boilers · United Kingdom, Ireland and RomaniaLOW MAINS VOLTAGE – legacy Keston Heat 45/55 error codeKeston documents “Mains voltage below the permitted level” for the legacy Heat 45, 55, 45P and 55P controller.…LOW WATER PRESSUREKeston · Legacy Keston Heat 45 and 55 commercial boilers · United Kingdom, Ireland and RomaniaLOW WATER PRESSURE – legacy Keston Heat 45/55 error codeKeston documents “Low water pressure” for the legacy Heat 45, 55, 45P and 55P controller. This is a…OUTSIDE SENSOR FAULTKeston · Legacy Keston Heat 45 and 55 commercial boilers · United Kingdom, Ireland and RomaniaOUTSIDE SENSOR FAULT – legacy Keston Heat 45/55 error codeKeston documents “Outside sensor fault” for the legacy Heat 45, 55, 45P and 55P controller. This is a…OVERHEAT LOCKOUTKeston · Legacy Keston Heat 45 and 55 commercial boilers · United Kingdom, Ireland and RomaniaOVERHEAT LOCKOUT – legacy Keston Heat 45/55 error codeKeston documents “Boiler overheat lockout” for the legacy Heat 45, 55, 45P and 55P controller. This is a…PCB FAULTKeston · Legacy Keston Heat 45 and 55 commercial boilers · United Kingdom, Ireland and RomaniaPCB FAULT – legacy Keston Heat 45/55 error codeKeston documents “Main controller fault” for the legacy Heat 45, 55, 45P and 55P controller. This is a…RETURN THERMISTOR FAULTKeston · Legacy Keston Heat 45 and 55 commercial boilers · United Kingdom, Ireland and RomaniaRETURN THERMISTOR FAULT – legacy Keston Heat 45/55 error codeKeston documents “Return thermistor fault” for the legacy Heat 45, 55, 45P and 55P controller. This is a…TOO MANY RESETSKeston · Legacy Keston Heat 45 and 55 commercial boilers · United Kingdom, Ireland and RomaniaTOO MANY RESETS – legacy Keston Heat 45/55 error codeKeston documents “Too many resets within 15 minutes” for the legacy Heat 45, 55, 45P and 55P controller.…