What's included in a boiler service

What should happen during a boiler service

There's no single published checklist that every engineer follows, so the fairest guide is what Dublin engineers say their own service covers. Stillorgan Gas publishes the longest list, 17 items, and the same checks turn up on the others (Stillorgan Gas, read 29 October 2026). In the order an engineer usually works:

1. A look over the boiler and the room.Visual damage, scorching, corrosion, the clearance from anything that can burn, and that the room has the ventilation the boiler needs.
2. The flue.Its condition, where it runs, where it ends, and a spillage test with the boiler running, so flue gases are going outside and not into the room.
3. The condensate drain.On a condensing boiler, the small plastic pipe that carries away acidic water. Blocked or frozen, it stops the boiler.
4. Burner, heat exchanger and probes.Stripped, cleaned and inspected. Dirt here is why an unserviced boiler burns badly and uses more gas.
5. Gas soundness and gas pressure.A soundness test on the appliance with the boiler running, and the burner pressure set to the maker's figure.
6. The controls and safety devices.The flame sensing control, the boiler thermostat, the system pressure and the expansion vessel charge.
7. A combustion efficiency test.A probe in the flue measures oxygen, carbon monoxide and temperature. Stillorgan Gas, Dublin Boiler Services and Liffey Heating all list it. It is the part a quick look-over skips.
8. The paperwork.A written service record, and often a Declaration of Conformance certificate for the appliance.

What the national providers say is in theirs

Bord Gáis Energy describes its one-off service as "19 checks and tests to I.S. 813:2017" with an RGI appliance conformance certificate, for a price that covers the first 45 minutes on site (Bord Gáis Energy). Energia sells a "28-point check" covering a service safety check, electrical checks and a boiler efficiency check, with a 30-day warranty on the service (Energia). Neither publishes the full list of points. Both were read on 22 October 2026.

What's not in a standard service

• Repairs and parts. If the engineer finds a worn fan, a weeping valve or a failing expansion vessel, that's a repair, quoted separately. Dewar Gas Service says so on its service page: parts and repair labour are extra (Dewar).
• Other gas appliances. A boiler service covers the boiler. A gas hob, fire or water heater is a separate job, and a landlord's Annex E inspection covers every appliance: see landlord gas safety certificate.
• Radiators and pipework. Bleeding radiators or balancing the system isn't part of a service unless the engineer includes it. Allgas lists venting the radiators in its price; most don't.
• A power flush. Cleaning sludge out of the whole system is a separate, much bigger job.
• Time beyond the limit. Where a price covers a set time, like Bord Gáis Energy's 45 minutes, an older or awkward boiler can run over it: €25 per 15 minutes on that plan.

Gas and oil: the same job, with two differences

An oil boiler service is the same idea, but the technician also fits a new burner nozzle and cleans or changes the oil filter, and it's done by an OFTEC-registered technician rather than an RGI. Published oil prices in Dublin run €80 to €220 against €110–€135 for most gas services. See oil boiler service.

The certificate you get

Any gas work by an RGI, including a service, must end with a Declaration of Conformance, also called a completion certificate. Safe Energy Ireland lists three: CERT 1 for a new gas connection, CERT 2 for a boiler replacement, and CERT 3 for "all other Gas Works i.e. appliance fits (except boilers), pipework, safety check, repair work and servicing of gas appliances". The RGI gives you the original white copy straight after the work (rgi.ie). Keep it with the boiler's warranty papers: most makers want proof of a yearly service to honour the warranty.

If the engineer finds a hazard

An RGI who finds a hazard has a duty to issue a Notification of Hazard to the owner or occupier, and may isolate the gas to the appliance or at the meter if safety calls for it, in a way that needs tools to undo (rgi.ie). It's not a sales tactic. It means don't use the appliance until it's fixed.

How to tell a full service from a quick look

• Ask if the burner and heat exchanger are cleaned, not just inspected
• Ask for the flue gas analysis printout or the readings on the record
• Ask what certificate you get, and that it's a CERT 3 Declaration of Conformance
• Check the engineer's RGI card, or their name on rgi.ie
• Ask what the price covers, and whether VAT is in it

Dublin engineers who publish a gas service price charge €80 to €179, and the middle half charge €110–€135. The spread is mostly what's included, so this list matters more than the headline number. See every published price.

Questions people ask