BoilerFaultCodesWhat the manual says
Manufacturer manualHot water demand
Shared across the ecoTEC plus range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
What causes this fault?
This code appears when the boiler's internal flow sensor detects water moving through the pipes after you open a hot water tap. It physically indicates that the internal diverter valve has shifted position to prioritise heating your water instead of your radiators. This is a normal functional message and does not indicate a mechanical failure or a breakdown.
DIY fix possible
This fault may be fixable without an engineer. Check your manual first.
Find a Gas Safe engineer
Search the official register →
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.
Related fault codes
All 77 fault codes on the ecoTEC plus
Seeing a different code? Every code this model can display, in one place.
Communication faultD.17F.00F.01F.02F.03F.10F.11F.12F.13F.20F.22F.23F.24F.25F.26F.27F.28F.29F.32F.35F.42F.49F.52F.53F.54F.56F.57F.61F.62F.63F.64F.65F.67F.68F.70F.71F.72F.73F.74F.75F.76F.77F.78F.83F.84F.85F.91F.92F.93S.11S.13S.14S.15S.16S.17S.20S.21S.22S.23S.24S.25S.26S.27S.28S.30S.31S.32S.34S.41S.42S.53S.54S.96S.97S.98