Judging Urgency: When is a Lockout Immediate?
While any lockout should be investigated, some situations demand immediate attention. If you smell gas at all, or suspect a carbon monoxide leak – evidenced by alarms, or symptoms like headaches and nausea – then this is an immediate emergency. Leave the property, call the Gas Emergency Service, and then us. Beyond that, if the lockout is persistent despite one cautious reset, or if it's accompanied by unusual noises, smells, or visual signs like black sooting, it's time for an urgent call to a qualified engineer.
- Smell gas – evacuate immediately
- Carbon monoxide alarm activated – evacuate immediately
- Persistent lockout after one reset
- Unusual noises or smells accompanying lockout
- Visible signs like sooting around the boiler

