With the first chilly mornings, a coughy boiler and lukewarm radiators: each autumn, technicians see a surge of emergency calls for preventable breakdowns. For specialists in air conditioning and plumbing, the message is clear: before winter, a few simple checks are enough to avoid discomfort, energy waste and risks to the installation. It remains to know where to begin and what to check.
Experts in air conditioning and plumbing sum up the priority into one clear directive: “Make sure to follow these steps to guarantee optimal operation,” they explain. Open valves, no leaks, correct pressure, purge the radiators, thermostat properly placed… This checklist, echoed by Spanish and French professionals, allows stress-free preparation for the boiler restart before winter. A routine of a few minutes that can prevent many unwanted surprises.
Boiler Restart: First Checks to Do Before Winter
Even before pressing the start button, the pros recommend a visual inspection. You should check that all supply and return valves are open, that pipes and radiators show no signs of moisture or drips on the floor. A leak, even small, ends up damaging the installation. Radiators should also stay clear, with no furniture, curtains or clothing placed on them.
Heat circulation in the rooms also plays a key role. A radiator jammed behind a sofa or a thick curtain mainly heats the wall, not the room. Experts also recommend taking advantage of the winter sun by lifting shutters and opening curtains during the day, then closing them in the evening. This simple habit reduces the need to call on the boiler before winter.
Boiler Pressure and Purging Radiators: the Adjustments Pros Recommend
Another essential point: the boiler pressure. On the pressure gauge, most manufacturers recommend a value between 1 and 1.5 bar for normal operation, as noted by the National Confederation of Installer and Fluid Associations (CONAIF). Low pressure prevents proper circulation of hot water, radiators remain tepid and the boiler may go into safety mode.
When a radiator is hot at the bottom but cold at the top, or it makes gurgling sounds, trapped air is often to blame. “Bleeding radiators is a fundamental task for the proper functioning of a heating system, because the presence of air can affect efficiency and increase energy consumption,” says Mario Rial Axpe, head of the technical department of CONAIF. He advises turning off the heating, gently opening the bleed screw, and waiting for the air to escape. “You must keep the valve open until the water exits steadily; that is how you know the intervention has been performed correctly. In this way, the radiator ejects the air it contains,” adds the CONAIF spokesman, before reminding that you should then recheck the pressure on the gauge.
Thermostat, Temperature and Safety: The Last Steps for Optimal Heating
Once the boiler and radiators are set, specialists urge you to look at the room thermostat. It should be placed away from a heat source or a draft, otherwise it may skew the measurement and cause the boiler to fire up too often. For comfort, they recommend a temperature around 21 °C, with every extra degree adding about 7% to the bill.
They also emphasize the value of thermostatic valves and programmable thermostats, which adjust heat to the rooms and to the time of day and, according to cited studies, offer energy savings of 8 to 13%. Safety counts just as much: clear air vents, a potential carbon monoxide detector, and seeking a professional if the pressure often drops or if some radiators stay cold.
