A boiler that has stopped is nearly always one of a small number of faults, and the job is to find out which before touching anything. If yours has gone off, call 01462 506 374 and speak to a Gas Safe registered engineer. We diagnose the fault, explain what caused it, and give you a fixed price before any repair work starts.

The faults behind most breakdowns

• Pressure dropping repeatedly, which is a leak or a failed expansion vessel rather than something a top-up fixes
• Repeated lockouts on ignition, often the ignition lead, electrode or gas valve
• No heating and no hot water, usually a diverter valve, pump or PCB fault
• Hot water but no heating, or the reverse, which points at the diverter
• Kettling and banging on start-up
• Hot water that runs hot, cools, then recovers
• A frozen condensate pipe, common on external runs during a cold snap

We find the fault, we do not just reset it

A boiler that locks out is telling you something. Resetting it clears the code and buys a few hours, but the condition that caused it is still there. The most common outcome of repeated resetting is the same fault returning with more damage behind it.

Every repair starts with a diagnosis: what the fault code was, what the readings are now, and what condition caused the appliance to protect itself.

What we check before quoting

• The fault code history stored in the appliance
• Gas rate and operating pressure against the data badge
• Flue gas analysis, including carbon monoxide output
• System pressure and expansion vessel charge
• Flow and return temperatures across the boiler and around the system
• The condition of the water in the system, which tells you whether sludge is involved

Kettling, and hot water that will not stay hot

These two symptoms usually share a cause, and it is the one fault where the local water supply genuinely changes the answer. Affinity Water measures the supply into St Albans at 337 mg/l of calcium carbonate, which is very hard on their own scale. Scale forms on the hottest surface in the appliance. In a combi that is the plate heat exchanger, which is why hot water runs hot, cools, then recovers. In a system boiler it is the primary exchanger, and the symptom is kettling and overheat lockouts.

That figure changes the recommendation, not just the diagnosis. Where we find scale-related failure we will tell you whether a magnetic filter, a system flush or water treatment is what stops it recurring, because replacing the part without addressing the water means doing it again.

The frozen condensate call

Every winter a proportion of breakdowns are simply a condensate pipe that has frozen where it runs outside. The boiler shuts down because it cannot discharge, and it displays a fault that looks alarming. Thawing the pipe restores it.

Where we see it repeatedly on the same property we will say so and explain what would stop it, such as re-routing the pipe internally or increasing its diameter. Fixing the cause is cheaper than an annual call-out.

Repair or replace, answered honestly

There is a point where repairing an old appliance stops making financial sense. We take a view on the age of the boiler, the cost of the part, whether other components are close to failure, and whether the appliance is still supported by its manufacturer.

If a repair is the right answer we repair it. If it is not, we will say so and explain why, and you are under no obligation to do anything about it on the day.

Boilers we repair

Worcester Bosch, Vaillant, Ideal, Baxi, Glow-worm, Viessmann, Potterton, Ferroli, Alpha, Main and Ariston, in combi, system and regular configurations. Our vans carry the common failure parts, so a large share of repairs are completed on the first visit.

When to turn the boiler off and call immediately

These are not repair matters. They are safety matters and they are treated differently.

Where we repair boilers in St Albans

Across the AL1 to AL4 postcodes. St Albans has a large stock of Victorian and Edwardian housing, much of it in conservation areas where what can be done to an external flue is constrained. Older properties here have frequently had heating systems extended rather than replaced, which is the usual route to mixed pipework and poor circulation.

Gas Safe registration

Working on a gas appliance without Gas Safe registration is illegal. Our registration number is 956889 and you are entitled to ask to see the card before an engineer starts. Vantage Plumbing and Heating is a limited company, number 13248357.

After the repair

Every repair carries a twelve month guarantee on our own labour. Where the fault was caused by scale or sludge we will tell you what would stop it recurring. You are not obliged to take it, but you will know.

Book a boiler repair in St Albans

Call 01462 506 374 and speak to an engineer.

Frequently asked questions

Do you repair boilers you did not install? Yes, regardless of who fitted the appliance.

Will you have the part on the van? We carry the common failure parts for the major brands. Where a part has to be ordered we will tell you at the point of diagnosis.

My pressure keeps dropping. Is that a repair? It is a symptom. It is usually either a leak somewhere in the system or a failed expansion vessel, and topping it up repeatedly hides the cause rather than fixing it.

Is a repair worth it on an old boiler? Sometimes. We give you the age, the part cost and an honest view, then you decide.

Can you repair it and service it in the same visit? Yes, and where the appliance is due it usually makes sense.

Related: boiler repair across Hertfordshire, boiler servicing, boiler installation, power flushing, plumbers in St Albans and all our services in St Albans.