First chilly mornings, a coughing boiler, lukewarm radiators: each autumn, craftsmen see emergency calls flood in 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, overconsumption and risks to the installation. It remains to know where to start and what to check.
Experts in air conditioning and plumbing summarize the priority in a single clear instruction: “Make sure to follow these steps to guarantee optimal operation,” they explain. Open valves, absence of leaks, correct pressure, bleeding the radiators, thermostat properly placed… This checklist, recalled 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: The Initial Checks to Do Before Winter
Even before pressing the start button, the pros advise a visual inspection. You must check that all supply and return valves are open, that the pipes and
the radiators do not show signs of moisture or droplets on the floor. A leak, even small, will eventually damage the installation. Radiators should also be kept clear, with no furniture, curtains or clothing resting on them.
The circulation of heat in the rooms also plays a key role. A radiator stuck behind a sofa or a thick drape mainly heats the wall, not the room. Experts also recommend taking advantage of the winter sun by lifting the shutters and opening the curtains during the day, then closing them in the evening. This simple reflex reduces boiler use before winter.
Boiler Pressure and Radiator Bleeding: The Settings Pros Recommend
Another essential point: the boiler pressure. On the manometer, most manufacturers recommend a value between 1 and 1.5 bar for normal operation, as noted by the National Confederation of Installers’ and Fluids Associations (CONAIF). Too low a pressure prevents proper circulation of hot water; radiators stay lukewarm and the boiler may go into safety shutdown.
When a radiator is hot at the bottom but cold at the top, or it makes gurgling noises, trapped air is often to blame. “Bleeding the radiators is a fundamental task for the proper functioning of a heating system, because the presence of air can affect its efficiency and increase energy consumption,” stresses Mario Rial Axpe, head of the technical department of CONAIF. He advises turning off the heating, gently opening the bleed valve, then waiting for the air to escape. “You must keep the valve open until the water comes out steadily; that is how you know the intervention was performed correctly. In this way, the radiator expels the air it contains,” adds the CONAIF spokesperson, before recalling that you should then recheck the pressure on the manometer.
Thermostat, Temperature and Safety: The Final Steps for Optimal Heating
Once the boiler and radiators are adjusted, specialists recommend looking at the room thermostat. It should be placed away from a heat source or a draft, to avoid skewing the reading and triggering the boiler too often. For comfort, they suggest a temperature around 21 °C, each additional degree adding about 7% to the bill.
They also emphasize the value of thermostatic valves and programmable thermostats, which adjust heat to rooms and times of day and offer, according to cited studies, energy savings of 8 to 13%. Safety matters just as much: clear ventilation openings, a possible carbon monoxide detector, and consulting a professional if the pressure frequently drops or if some radiators stay cold.
