You hear it all the time: “You should get your boiler serviced once a year.”
But what actually happens in that hour the engineer’s in your cupboard? Are they really doing much, or is it just a quick look, a sticker, and off they go?
Here’s what a proper annual boiler service should look like, step by step, with rough timings – so you know what to expect when someone like East and Gray turns up at your door.
How Long Should a Boiler Service Take?
For a normal home boiler, you’re usually looking at:
- Around 45–60 minutes for a modern combi or system boiler in decent condition
- Up to 90 minutes if access is awkward, the boiler’s older, or there are issues to investigate
If someone is in and out in 10–15 minutes, that’s more of a quick glance than a proper service.
Step 1: Quick Chat and Safety Checks (5–10 minutes)
First, the engineer shouldn’t just walk in and head straight for the boiler without saying a word.
They’ll usually:
- Ask how the boiler’s been behaving – any noises, leaks, pressure drops, or error codes
- Check the area around the boiler is safe and has enough ventilation
- Have a look at the flue outside to make sure it’s in a sensible, safe place
You’re absolutely allowed to ask to see their Gas Safe ID card. Anyone from East and Gray will happily show it – it’s part of the job.
Step 2: Visual Check of the Boiler and Pipework (5–10 minutes)
Next, they’ll give everything a good once-over:
- Any signs of rust, staining, or water marks on or around the boiler
- Condition of the pipework and joints
- Any obvious drips, damp patches, or dodgy-looking fittings
- The condensate pipe (especially if it runs outside and could freeze)
This is where a lot of early problems are spotted – before they turn into a full breakdown.
Step 3: Taking the Case Off and Looking Inside (10–15 minutes)
Now the interesting bit.
The engineer will carefully remove the boiler’s front cover and look at:
- The burner and heat exchanger
- Ignition and flame sensor
- Seals and gaskets
- Fan and other moving parts
- Wiring and connections
They’re checking for things like:
- Soot or debris build-up
- Overheating marks
- Worn or perished seals
- Anything that looks unsafe or likely to fail soon
When we do this at East and Gray, this is often where we catch “future problems” before they become “no heating” problems.
Step 4: Cleaning the Important Bits (10–20 minutes)
A proper service isn’t just looking – there should be some actual cleaning involved.
Depending on your boiler, the engineer may:
- Clean the burner
- Check and clean the heat exchanger where needed
- Empty and clean the condensate trap
- Clean or check the ignition and flame sensors
This helps the boiler burn fuel properly, run more quietly, and reduces the chance of it suddenly locking out when you really need it.
Step 5: Gas and Flue Tests (10–15 minutes)
This is the safety-critical part.
The engineer will:
- Check the gas pressure and/or gas rate to make sure the boiler is getting what it needs
- Use a flue gas analyser to test the gases coming out of the flue
- Compare the readings to the manufacturer’s figures
If something’s off, they’ll try to adjust it. If it can’t be brought into line, they’ll explain what’s wrong and what needs doing next.
This is about keeping you safe and making sure the boiler isn’t wasting fuel.
Step 6: Running the Boiler and Checking the System (10–15 minutes)
Once the inside checks and cleaning are done, they’ll put the boiler through its paces:
- Turn the heating and/or hot water on
- Check the system pressure and top up if needed
- Make sure the boiler fires up properly and settles down without strange noises
- Test the room thermostat and any other controls
- Listen out for banging, gurgling, or kettling sounds
If your radiators are on, they might also have a quick feel for cold spots or obvious circulation issues.
At East and Gray, we use this bit to make sure the boiler isn’t just “passing tests” but actually behaving properly in real life.
Step 7: Putting It Back Together and Final Safety Checks (5–10 minutes)
Before they pack up, the engineer will:
- Refit the boiler case properly and securely
- Check again for any gas leaks with the right equipment
- Make sure there are no water leaks after everything’s been disturbed
- Confirm the flue is sealed and safe
Then they should tidy up and leave things as they found them.
Step 8: Paperwork, Stickers, and a Quick Chat (5–10 minutes)
The last bit is important and often rushed – but shouldn’t be.
You should get:
- The service record/benchmark filled in and signed
- Any readings or key results noted down
- A clear explanation of anything they’ve found or fixed
- Honest advice if something might need attention soon
This is your chance to ask questions like:
- “Is my boiler still a good one or nearly at the end of its life?”
- “Is there anything I can do to look after it between services?”
- “Should I be thinking about flushing the system or adding filters/softeners?”
When we visit as East and Gray, we always leave a few minutes at the end just to talk things through in normal language, not boiler-speak.
What a Boiler Service Won’t Do
It’s worth being clear on what a service isn’t:
- It’s not a full system power flush
- It won’t magically fix a boiler that’s already unsafe or badly installed
- It doesn’t guarantee the boiler will never break down
But it does:
- Help keep the boiler running as safely as possible
- Support efficiency so you’re not burning money
- Catch problems early before they get expensive
- Keep most boiler warranties valid (many insist on yearly servicing)
How Often Should You Get It Done?
For most homes:
- Once a year is the sweet spot
- Ideally before winter so you’re not discovering issues on the first cold night
If you’re a landlord, you’ve also got legal gas safety responsibilities – combining the safety check with a proper service is usually the smart move.
Annual Boiler Service With East and Gray
If your boiler service is due (or long overdue), and you’d like it done properly rather than rushed, East and Gray can help.
With us, you get:
- A Gas Safe registered engineer
- A thorough service, usually around 45–60 minutes
- Clear explanations of what we’ve done and what we’ve found
- Straightforward advice if anything needs fixing now or keeping an eye on
If you’re in Hertfordshire, including Harpenden, Borehamwood, St Albans, Radlett, and Welwyn Garden City, and want your boiler checked over before it lets you down, get in touch with East and Gray to book your annual service. We’ll keep it simple, safe, and as stress-free as possible.
