Questions & Answers

A standard service covers the essentials: flue gas analysis, gas pressure and flow check, inspection of the flue and the boiler's interior for leaks or wear, removal and cleaning of the condensate trap, check and recharge of the expansion vessel pressure, a gas leak check inside the boiler, removal and cleaning of the magnetic filter, and a digital service record and certificate at the end. It's a thorough check — not a box-ticking exercise.

I recommend a full service every 2 to 5 years. It includes everything in a standard service, plus: removal, cleaning and inspection of the burners, access and cleaning of the main heat exchanger, replacement of burner gaskets and sump seals if they need it, a water quality check including pH and inhibitor levels, bleeding of all accessible radiators, a check of the radiators' heating performance, and my recommendations for any further work. If something needs attention, I'll tell you — and I won't inflate the scope to make it sound worse than it is.

I service Vaillant, Worcester Bosch, Viessmann, Baxi, Potterton, Ideal, Alpha, Glow Worm, Vokera, Main, and Keston boilers. Between those brands, I cover the vast majority of what you'll find in homes across Kent.

I don't work on electric boilers, LPG boilers, oil boilers, or commercial boilers. I'm a natural gas specialist — those other types need engineers with different qualifications and equipment.

No — a service is preventative maintenance, not a repair. If I find a fault during the service, I'll flag it and we can discuss getting it fixed separately. The cost of repairs isn't included in the service price.

No, and I won't pretend otherwise. A service significantly reduces the risk of a breakdown, but no engineer can guarantee a boiler will never develop a fault. Boilers are mechanical systems — things wear out. What I can guarantee is that I'll do a thorough job and give you an honest picture of your boiler's condition.

Most likely a faulty flow switch or a stuck diverter valve. The diverter valve is the component that switches between heating mode and hot water mode — when it gets stuck, one or the other stops working. It's a common fault and usually straightforward to fix.

A faulty motorised valve is the most common culprit here. The motorised valve controls which circuit gets hot water — when it fails, the hot water cylinder stops getting heat even though the heating side carries on fine.

Again, a stuck diverter valve is the usual suspect — but it's worth checking your room thermostat and programmer first before booking a repair. Make sure the heating is actually switched on and the thermostat is turned up. If everything's set correctly and the radiators still won't heat, you likely need a repair.

Could be a faulty motorised valve, or it might be something as simple as the programmer or room thermostat not being set correctly. Check those first — make sure heating is switched on and the thermostat is turned up above room temperature. If that all checks out and the radiators are still cold, give me a call.

Dropping pressure usually points to one of three things: a leak somewhere in the system or the boiler itself, a faulty expansion vessel, or water escaping through the pressure relief valve. The PRV is usually a copper pipe that exits through an outside wall — if it's dripping, that's a clue. Don't keep topping up the pressure without finding out why it's dropping.

That hot-and-cold fluctuation is usually down to a blocked plate heat exchanger — limescale builds up inside and restricts water flow. If it's only happening in the shower, the shower cartridge is more likely the problem (and that's not a boiler issue at all).

Look up the fault code on the manufacturer's website — most of them publish full lists of codes with descriptions. Search for your boiler make and model plus the code and you should get a clear answer. Some codes you can reset yourself; others mean you need an engineer. If you're not sure, give me a ring and I'll tell you whether it's something to worry about.

That banging is nearly always a sign of water overheating somewhere in the system — usually caused by a failing pump that isn't circulating water fast enough. It could also be air in the system or a blocked main heat exchanger. Either way, don't ignore it. Persistent overheating puts stress on the heat exchanger and can turn a simple repair into a much more expensive one.