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When your boiler stops working in the middle of winter, you don’t have time to figure out who to call. You just need heat-fast. That’s when the big question pops up: Do plumbers handle boilers? The short answer is yes-but not all plumbers are created equal. Some know boilers inside and out. Others barely know the difference between a radiator and a water heater. Knowing who to call can save you money, time, and a cold house.
Not Every Plumber Can Fix a Boiler
Plumbing and boiler repair overlap, but they’re not the same thing. A plumber deals with water pipes, drains, faucets, and water heaters. A boiler technician deals with gas lines, pressure systems, heat exchangers, thermostats, and combustion safety. Both work with water, but boilers are gas-fired heating systems that turn water into steam or hot water for your whole house. That’s a whole different skill set. In New Zealand, boilers are often powered by natural gas or LPG. That means they’re not just plumbing-they’re gas appliances. Gas work requires special certification. In Dunedin, anyone working on gas boilers must hold a Gasfitter Level 2 license from the Gas Industry Company (GIC). Without that license, a plumber can’t legally touch the gas side of your boiler. And if they try, you’re risking carbon monoxide leaks, fire hazards, or invalidating your home insurance.What a Licensed Boiler Technician Can Do
A qualified boiler technician-whether they call themselves a plumber, a heating engineer, or a gasfitter-can do all of this:- Diagnose why your boiler won’t ignite or keeps shutting off
- Check and adjust gas pressure and airflow
- Replace faulty heat exchangers, pumps, or thermostats
- Clear blockages in condensate pipes (a common issue in cold climates)
- Perform annual safety checks and issue a compliance certificate
- Install new boilers and connect them to gas and water lines
When a Regular Plumber Is Enough
There are times when a standard plumber is perfectly fine. If your boiler is working fine but you have a leak in the pipe leading to your radiator, or if your water pressure drops because of a faulty valve on the expansion tank, a plumber can handle that. They can also replace a broken pump if it’s an external component and not tied to the boiler’s internal gas system. But here’s the catch: if the problem is anywhere inside the boiler unit itself-especially if it’s making strange noises, showing error codes, or not heating water properly-you need a gas-certified technician. A plumber might replace a part, but if they don’t understand how the gas valve interacts with the ignition system, they’ll just be guessing.
What to Look for When Hiring Someone
Don’t just pick the first name you find on Google. Ask these three questions before they even step into your home:- Do you have a Gasfitter Level 2 license? Ask to see it. Legitimate technicians carry it on their phone or in their wallet.
- Do you specialize in boilers, or do you do mostly taps and toilets? If they say they do everything, they might not do anything well.
- Can you show me a recent boiler service certificate? Reputable companies keep records of every job. Ask to see one.
Boiler Brands and Common Failures in New Zealand
Most homes in Dunedin and Otago have boilers from brands like Baxi, Vaillant, Worcester Bosch, or Ideal. Each has common failure points:- Baxi: Faulty printed circuit boards (PCBs) after 8+ years, especially in humid coastal areas.
- Vaillant: Condensate pipe freezes easily in winter. A simple insulation wrap fixes it 80% of the time.
- Worcester Bosch: Pressure drops slowly over time-usually due to a tiny leak in the system, not the boiler itself.
- Ideal: Ignition failure caused by dirty flame sensors. Easy fix, but only if the tech knows where to look.
Why DIY Is a Bad Idea
You might be tempted to Google your boiler’s error code and try to reset it. Or maybe you’ve seen a YouTube video about cleaning a flame sensor. Don’t. Boilers are high-pressure, gas-powered systems. One wrong move can trigger a gas leak, a carbon monoxide buildup, or an electrical short. In 2024, WorkSafe New Zealand reported 17 incidents of unsafe boiler repairs by unqualified people-two of them resulted in hospitalizations due to carbon monoxide poisoning. Even if you fix it yourself, you won’t get a legal compliance certificate. That’s required if you sell your house. Buyers in Dunedin routinely ask for proof of boiler safety checks. Without it, your sale could stall-or fall through.
What’s the Cost?
A boiler service with a licensed technician in Dunedin usually costs between $150 and $250. That includes a full safety check, pressure test, and written report. Repairs vary: replacing a pump might be $400, a new heat exchanger $1,200+, and a full boiler replacement $4,000-$7,000 depending on size and efficiency rating. Don’t fall for the $99 boiler service. That’s usually a sales tactic. The technician will find a problem that needs a $1,200 fix-and you’ll feel pressured to pay on the spot. A proper service doesn’t push you to buy. It tells you what’s working, what’s failing, and what to expect next year.When to Replace Instead of Repair
Here’s a simple rule: if your boiler is over 12 years old and the repair cost is more than half the price of a new one, replace it. New boilers use 90%+ efficient condensing technology. Your old one might be running at 70%. That’s a $400-$600 yearly waste on gas bills. Also consider this: if you’ve had three repairs in the last two years, you’re in repair mode. It’s not a fix-it’s a countdown. A new boiler will pay for itself in energy savings within 4-5 years.Final Tip: Don’t Wait for Winter
Boiler failures don’t wait for convenient times. But you can avoid the panic. Schedule a service in early autumn-April or May. That’s when technicians have time. You’ll get better rates, faster response, and peace of mind before the cold hits. If you’re unsure who to call, ask your local energy provider. They often have a list of certified gasfitters in your area. Or check the Gas Industry Company’s public register. You can search by license number or suburb. No guesswork. No scams. Just qualified help.Can any plumber fix my boiler?
No-not all plumbers can. Only those with a Gasfitter Level 2 license are legally allowed to work on the gas components of a boiler. Many plumbers handle water pipes connected to boilers, but internal repairs require gas certification. Always ask for proof of licensing before they start work.
What’s the difference between a boiler and a water heater?
A water heater only provides hot water for taps and showers. A boiler heats water for both your taps and your radiators or underfloor heating. Boilers are connected to a whole-house heating system and are usually gas-powered. Water heaters are often electric or solar and don’t heat your home.
Why does my boiler keep turning off?
Common causes include low water pressure, a frozen condensate pipe (especially in winter), a faulty thermostat, or a blocked flue. Most of these are easy fixes-but only if you have the right technician. A boiler that shuts off repeatedly is a safety risk. Don’t ignore it.
How often should I service my boiler?
Once a year. Annual servicing keeps your boiler running safely and efficiently. It also keeps your warranty valid and ensures you get a compliance certificate if you ever sell your home. Skipping service can lead to expensive breakdowns and even void your insurance.
Is it worth repairing an old boiler?
If your boiler is over 12 years old and the repair costs more than half the price of a new unit, it’s usually better to replace it. Older boilers are less efficient, use more gas, and are more likely to break again. A new model can cut your heating bills by 30% or more and pay for itself in a few years.