BoilerFaultCodes E8 High
Your boiler has detected that the water leaving it is significantly hotter than the water returning, meaning heat isn't circulating properly through your radiators.
Call an engineer soon
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Difference between flow and return temperature too large
Typical repair cost £150-350 (including labour)
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like E8 — no call-out fees, no surprises.
Affiliate links — we may earn a commission at no extra cost to you.
Remeha Quinta 30 is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
Affiliate links — we may earn a commission at no extra cost to you.