108
FAULT CODE
ATAG
Low Water Pressure — Refill Required
Low Severity
DIY Check Possible
On ATAG IC/IS boilers, code 108 indicates the system pressure needs filling (below 0.5 bar). Also shown as 1P4 when between 0.5 and 0.8 bar.
Step-by-Step Fix Guide
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Step 1
Repressurise to 1.5 bar using the filling loop
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Step 2
Reset the boiler
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Step 3
If pressure drops again, contact a Gas Safe engineer
Gas Safe Reminder
Work on gas appliances must be carried out by a Gas Safe registered engineer. The steps above cover safe checks a homeowner can perform - any internal component replacement requires a qualified professional. If in doubt, always call an engineer.