Central Heating Not Working Properly? September Checks Every Homeowner Should Make
Run your heating for an hour this month and work through this checklist — it's the fastest way to find the faults that ruin December.
The best diagnostic tool for a heating system is an hour of running it while the weather is still mild. Do it now and any fault becomes a planned job. Do it in December and it becomes an emergency. Here is the checklist our engineers use before recommending central heating repairs in North London.
Step 1: Run the heating for a full hour
Set the thermostat well above room temperature and let the whole system come up to heat. Short bursts hide problems; an hour reveals them.
Step 2: Touch every radiator, top and bottom
Cold at the top = air, bleed it. Cold at the bottom = sludge, and a candidate for power flushing. Completely cold = a seized valve or a badly balanced system. Warm but never hot = flow rate issues. Note which rooms, because that pattern tells us a lot.
Step 3: Watch the pressure gauge
It should sit around 1–1.5 bar cold and rise slightly when hot. A gauge that creeps to 3 bar suggests a failed expansion vessel; one that steadily falls means a leak that needs finding.
Step 4: Listen
Banging or kettling from the boiler, humming from the pump, or ticking pipework under floorboards all point to specific faults — scale, a failing pump, or pipes clipped too tightly. None of them get better on their own.
Step 5: Test the controls
Does the room thermostat actually switch the boiler? Do the TRVs turn freely, or have they stuck open after a summer untouched? Is the programmer still on a summer schedule? Upgrading to smart thermostats solves control problems and cuts waste at the same time.
Step 6: Check the magnetic filter
If your system has one, it should be cleaned annually. A filter thick with black iron oxide is a warning that the same sludge is sitting in your radiators and heat exchanger.
Common faults in older North London homes
In Victorian and Edwardian Barnet properties we typically find undersized microbore pipework, radiators never rebalanced after an extension, and 20-year-old zone valves. All fixable — often with targeted heating repairs rather than a whole new system.
Book a heating check
Our engineers run a full heating health check across Barnet and North London: pressure, flow, balance, controls, filter and boiler performance, with a written report and fixed-price options for anything found. Book yours while diaries are still open.