BoilerFaultCodes 20
Central Heating NTC Fault
Baxi Ecoblue18 System ErP Fault codes & diagnostics
28 fault codes with plain-English explanations, severity ratings, DIY guidance, and repair cost estimates.
System Gas
GC Number 41-470-25
Download the Baxi Ecoblue18 System ErP manual
PDF
Versions & GC numbers
The fault code is already on your display
Note it down before pressing reset — resetting clears the code immediately. How to read fault codes →
Severity at a glance
Each cell = one fault code. Hover to identify. 28 Unrated
Which version do you have?
The GC number on your boiler's data badge identifies the exact appliance and production years, as recorded in the UK Product Characteristics Database.
| GC number | Appliance (register name) | Produced |
|---|---|---|
| 41-470-25 | Ecoblue18 System ErP | 2015–present |
Appliance names and production years are taken from the UK Product Characteristics Database (the SAP/SEDBUK register). Where a GC number is also printed in this model's own manufacturer manual, both sources were checked to agree.
Just want the most common Baxi Ecoblue18 System ErP faults?
The top 6 problems in plain English — with causes, DIY checks and repair costs.
Fault codes
All 28 documented codes
Tap any card for details
28
Flue NTC Fault
40
Central Heating Return NTC Fault
109 R
Possible Circulation Fault
110 R
Safety Thermostat Operated (pump fault)
111 R
Safety Thermostat Operated (over temperature)
117
Primary System Water Pressure Too High
118
Primary System Water Pressure Too Low
125 R
Circulation Fault (Primary)
128
Flame Failure (no lock-out)
Showing 11–20 of 28
130
Flue NTC Operated
133
Flame Failure fault
133 R
Interruption Of Gas Supply or Flame Failure
151 R
Flame Failure
160 R
Fan or Fan Wiring Fault
321
Faulty component (referenced in troubleshooting flowchart)
384
False Flame
B
Switch to DHW mode maximum flow & press reset
C
Fan connections check / Fan jammed or faulty wiring
D
Temperature sensor faulty
Showing 21–28 of 28
E
Gas at burner
E118
low water pressure
F
Ignition electrode/lead, connection, or spark gap issues
G
Gas supply pressure or combustion set / Flame sensing electrode issues
H
Safety Thermostat operated or faulty
I
CH system pressure less than 0.5 bar or greater than 2.7 bar on digital display
J
System air / Flow temperature sensor issues
K
Temperature sensors faulty or heat exchanger obstruction
Boiler cover options
Avoid the next call-out bill
Monthly cover means no unexpected bills when your boiler breaks down.
Approved partner
Get a quote →
Domestic Appliance Guard
Unlimited call-outs, 24/7 helpline, no price-hike promise
Affiliate links. We may earn a commission at no extra cost to you.