Low
2 08 on Ariston Clas HE 24

Your boiler has detected that the internal water temperature is extremely low and is running its built-in protection mode to prevent the pipes from freezing.

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

Collector frost protection temperature

From this model's manual
Verified against the Ariston Clas He 24 installation & service manual, page 37.
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

Ensure the boiler power supply is kept switched onCheck that the gas supply is active so the burner can fireEnsure internal doors are open to allow ambient heat to circulate near the boilerWait for the protection cycle to complete and the water temperature to rise

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 2 08: 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

2 02View →2 04View →

Related guides you might find useful

Is boiler cover worth it?

Break-even maths on monthly cover.

Read →

When to replace your boiler

7 signs repair isn't worth it anymore.

Read →

New boiler cost 2026

Realistic UK prices for a swap.

Read →