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Gas in much of the town, oil in the country behind it — most boiler trouble announces itself the same way, and most of it has a calm first response.
Notice summary: check pressure, power and controls before declaring the boiler lost — the gauge should read roughly 1 to 1.5 bar cold, the timer and thermostat should actually be calling for heat, and one reset is permitted. If you smell gas, that outranks everything: leave and call 0800 111 999. For all else, ring 020 4577 2888 and describe what the boiler is doing.
Leave the property, touch no switches, strike no flame, and call the National Gas Emergency Service on 0800 111 999 from outside. A gas smell is never a plumbing call first.
Much of Carrickfergus town is on mains gas, so this notice is posted first and kept polished. If you smell gas — near the boiler, at the hob, anywhere — the drill admits no shortcuts: everybody out, doors left open behind you if that's the work of a second, no light switches on or off, no phones used indoors, nothing that can spark. From a safe distance outside, call 0800 111 999, which is staffed around the clock.
Only when the emergency service has made the situation safe does the repair become an ordinary job. And a general point of law worth knowing, not a claim about anyone in particular: work on gas appliances must be carried out by a Gas Safe registered engineer. Whoever comes to your gas boiler, asking to see identification is normal, expected and never rude.
Sealed systems like to sit near 1 to 1.5 bar cold; below that, many boilers simply refuse duty. Top up through the filling loop with the manual open — and note the date you did it.
The round gauge on the front of the boiler is the ship's log of your heating system. Most sealed systems are happy between 1 and 1.5 bar when cold — your manual gives the exact figures — and when the needle sinks below 1 bar the boiler may lock out or heat feebly. Repressurising through the filling loop, usually a braided hose or built-in lever arrangement under the boiler, is a job householders do every winter: valves open slowly, watch the needle climb, close firmly at the target, never overshoot.
The seamanlike habit is to log it. One top-up after bleeding radiators is nothing. A boiler that needs the loop again within days or weeks is telling you the system is losing water somewhere — a weeping radiator valve, a joint under a floor — and each refill quietly feeds the leak. That pattern is worth a professional eye, and the hidden leaks notice explains where the water usually goes.
High pressure carries its own warning: much above 2.5 to 3 bar, suspect a filling loop left cracked open or an expansion vessel fault, and expect the relief valve to start dumping water through the outside wall pipe if it isn't seen to.
Write the code down before you touch anything, try one reset, and if the fault returns, stop. Repeated resets can mask a fault the engineer needs to see.
Modern boilers signal like ships: a flashing letter-and-number code on the display that tells an engineer half the story before the toolbox is open. Your first job is clerical — note the exact code, and what the boiler was doing when it appeared. Your manual (or the maker's website) will translate it roughly: low pressure, ignition failure, sensor fault, frozen condensate.
One reset is fair practice; some faults genuinely are one-off trips. But a code that comes straight back is a fault, not a mood, and pressing reset over and over is like repeatedly restarting an engine that's warning you about oil. In frosty weather, one code family is worth knowing about: a frozen condensate pipe — the plastic pipe running from the boiler to an outside drain — stops many condensing boilers entirely, and pouring warm (not boiling) water along the frozen section outside often restores the boiler without a visit. Anything beyond that, ring with the code to hand.
Check the tank level before anything else — an empty or near-empty tank explains a great many silent oil boilers. If it ran dry, the line usually needs bleeding before it fires.
Step inland from the town — towards Ballycarry, Straid and the townlands above Woodburn — and oil tanks appear in gardens, as they do across much of rural Northern Ireland. When an oil boiler falls silent, walk to the tank first: sight gauges stick and mislead, so check honestly. A tank run to the dregs pulls air and sediment into the fuel line, and the burner will typically lock out even after a refill until the line is bled and the filter checked — an ordinary job for a heating engineer, not one to improvise.
Oil systems also reward a glance at the simple things: the burner's own power switch and fused spur, the boiler thermostat, and in hard frosts the external fuel line, which can wax and thicken in extreme cold. And the same identification instinct applies as with gas: oil heating has its own competence schemes, and asking who you're dealing with before work starts is plain good practice on any fuel.
Cold at the top means air — bleed the radiator. Cold in the middle means sludge. Banging and rumbling from the boiler deserves a shutdown and a call.
A radiator warm at the bottom and cold along the top is carrying trapped air, and bleeding it — radiator key, quarter turn, hiss, close when water beads — is five minutes of honest work. Remember that on a sealed system, bled air lowers the pressure, so glance at the gauge afterwards and top up if the needle has sunk. A radiator cold in the middle and at the bottom is a different cargo: magnetite sludge, which gathers over years and calls for a system flush rather than a key.
Noise is its own signal flag. A gentle hum is life; kettling — a rumble or bang like a kettle boiling dry, common where scale has built on the heat exchanger — is the boiler asking to be switched off and looked at. The same goes for repeated ignition attempts that end in silence, or water appearing beneath the casing. Shut it down at the control, leave the casing shut (opening it is the engineer's job, on any fuel), and raise the number with a plain description of the sound.
No — it outranks every other notice on this page. Leave the property at once, touch no light switches, strike no flame, and from a safe distance outside call the National Gas Emergency Service on 0800 111 999. Only once the gas side is declared safe does the boiler repair itself become a job for an engineer.
Once or twice a year after bleeding radiators is ordinary housekeeping. Needing the filling loop every few weeks — or worse, every few days — means the sealed system is losing water somewhere, and each top-up is feeding a leak you haven't found yet. Stop refilling and start investigating; the hidden leaks notice on this site explains where that water tends to be going.
By law, work on gas appliances must be carried out by a Gas Safe registered engineer — that's the general rule across the UK, not a claim about any particular person. When any engineer arrives to work on a gas boiler, asking to see their identification is normal and expected. Oil boilers have their own competence schemes, and the same instinct applies: ask who you're dealing with.
Running an oil tank to the bottom pulls air and sediment into the fuel line, and the burner usually locks out even after the tank is refilled. The line generally needs to be bled and the filter checked before it will fire again — a routine job for a heating engineer, but not one to improvise with tools you haven't used before. Refill, then ring.
The main notice — how the line works and the waters it covers.
Go to home →Close the stopcock before all else — the full standing orders.
Read the notice →What to attempt, and when it's NI Water's sewer instead.
Read the notice →How charging works and the questions to put before work starts.
Read the notice →Pressure, timer, tripped switch, immersion — checks in order.
Read the notice →Gentle thawing from the tap end, and never with a flame.
Read the notice →Damp patches, slipping pressure and the stopcock test.
Read the notice →Gauge read, code noted, tank checked? Then ring any hour — gas or oil, town terrace or Islandmagee farmhouse — and describe it plainly to a local plumber.
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