Low
S.28 on Heatline CaprizPlus 24a

Your boiler is temporarily pausing the hot water production to prevent the system from overheating after a heating cycle.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

The boiler blocks tank reheating after a reheating cycle.

From this model's manual
Verified against the Heatline Caprizplus 24a installation & service manual, page 26.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Check if the hot water temperature is set too high and lower it slightlyEnsure all radiator valves are open to allow heat to dissipateWait up to 20 minutes for the boiler to automatically reset and start again

Find a Gas Safe engineer
Search the official register →
Boiler cover options

Avoid the next call-out bill

A cover plan would handle faults like S.28: no call-out fees, no surprise bills.

Approved partner
Domestic Appliance Guard
Unlimited call-outs, 24/7 helpline, no price-hike promise
Get a quote →

Affiliate links. We may earn a commission at no extra cost to you.

Related fault codes

S.27View →S.20View →

Related guides you might find useful

No hot water but heating works

Almost always a stuck diverter valve on combis.

Read →

Banging / kettling / whistling noise

Each noise points to a different fault.

Read →

Boiler keeps cutting out

Lockout fault with a reset-needed pattern.

Read →