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No Heating or No Hot Water? 10 Quick Checks Before You Call | ARA Services

No Heating or No Hot Water?
10 quick checks before you call

This is the “it’s gone cold and I need it back” page. No waffle, no deep theory. Just the fastest, safest checks we tell people over the phone in London. If you get stuck halfway through, it’s usually quicker to book proper boiler repairs than keep guessing.

Call a Gas Safe engineer Book local boiler repair Start the 10 checks

People usually find us by searching “boiler repair near me” or “gas boiler repair near me”. If that’s you right now: do these checks once, calmly — then stop and call if it’s still dead.

Stop and get help if you notice ANY of these. Gas smell, a carbon monoxide alarm, soot marks around the boiler/flue, dizziness/headaches that ease when you leave the room, or water dripping onto electrics. Use our simple routing page: Is this a boiler emergency? If it’s clearly unsafe, go straight to: emergency boiler help.

10 quick checks (in a sensible order)

Little true story: half the “emergency boiler repair” calls we get on a freezing evening are one of three things — a tripped fused spur, a programmer that’s quietly set to “off”, or pressure that’s dropped just low enough to lock the boiler out. Annoying… but fixable.

1) Check the boiler has power

Look for lights/display on the boiler. If it’s blank, check the fused spur (usually a switch near the boiler) and the consumer unit.

If the spur switch feels warm, smells “electrical”, or looks damaged — stop and call.

2) Thermostat: turned up and calling for heat?

Turn the room stat up a few degrees above room temperature. If it’s a wireless stat, check batteries.

If it’s a smart thermostat, confirm the schedule didn’t drop into “away” mode.

3) Programmer/timer: is it set to ON (not just timed)?

Set heating and hot water to “ON” temporarily (not “AUTO”) so you can test properly.

You’d be surprised how often someone bumped it while cleaning the kitchen.

4) Do you have hot water but no heating (or the other way round)?

This matters. “No heating” can be controls/zone/valve related. “No hot water” can point to different components.

If it keeps turning off with a fault code, use: lockouts & error codes.

5) Pressure check (quick concept, not a deep dive)

Most combi boilers like the pressure around 1.0–1.5 bar when cold. If it’s down near 0, many boilers won’t run.

If you top up and it drops again soon after, don’t keep refilling — that’s a separate diagnosis: boiler losing pressure causes.

6) If pressure is low, top up once (carefully)

Use the filling loop (varies by boiler). Open slowly, watch the gauge rise, and stop around 1.2–1.5 bar. Close everything properly.

If you’re unsure where the filling loop is, don’t force anything — call us and we’ll talk you through it.

7) Reset once (only once)

If your boiler has a reset button, reset a single time after you’ve checked power/controls/pressure. Don’t get into “reset roulette”.

Repeated resets can make some faults worse (and it also muddies diagnosis). More here: why boilers lock out.

8) Frozen condensate pipe (common in cold snaps)

If it’s been properly cold and the boiler’s on an outside wall / balcony cupboard, the condensate pipe can freeze and stop the boiler.

Safe approach: warm water (not boiling) over the outside pipe section, or a hot-water bottle held against it. Don’t use naked flames. Don’t pour boiling water onto plastic pipework.

9) Radiator valves & a “stuck” feeling

Make sure at least one radiator is open. If you’ve recently bled radiators, re-check pressure afterwards (it often drops).

If you hear loud banging/whistling, that’s a different path: banging / kettling noises.

10) Look for obvious water (but don’t poke around)

If you can see water under/around the boiler, stop trying to run it and keep electrics dry.

Immediate next step is here: boiler leaking — what to do now.

If you’ve done the checks and it’s still not firing — that’s usually the point where a proper diagnostic visit saves money. The aim is a safe fix, not “let’s keep pressing buttons until something happens”.

Done the checks and it’s still dead?

That’s the moment to stop guessing. We’ll diagnose it properly, explain what failed, and fix it safely. If you’re searching for local boiler repair or a genuine boiler repair near me option in London, this is exactly what we do every day.

Scenario CTA: if you’re stuck in a cold flat and you’ve got no hot water for showers, call us on +44 7727 154746 — we’ll tell you straight whether it sounds urgent or bookable.

Quick FAQs (different questions, different vibes)

My boiler pressure is at 0 — can I just keep topping it up?

Top up once to get the boiler running, sure. But if it drops again soon after, stop refilling. Constant top-ups can trigger other issues. Use the diagnosis page: why boilers lose pressure.

Is it safe to reset the boiler a few times?

Once is fine. More than that turns into guesswork and can make certain faults worse. If it locks out again, note the code and read: lockout causes & what info helps.

I think the condensate pipe is frozen — what’s the safest way?

Warm water (not boiling) over the outside section, or a hot-water bottle against the pipe. Avoid kettles of boiling water and never use a naked flame. If you’re unsure, call and we’ll guide you.

It’s no heating but the hot water is fine — does that mean it’s not “serious”?

Not necessarily. It can be controls, a zone valve, pump/circulation issues, or settings. If you’ve checked the thermostat and programmer properly and it’s still not responding, it’s usually a diagnostic visit. Book here: boiler repairs.

When should I treat it as an emergency?

Any gas smell, CO alarm, soot marks, or water affecting electrics: treat as urgent and follow: the emergency checklist, then go to emergency boiler help.