It is Halloween, and with the heating season under way, this is also when the boiler room starts to “talk”. Humming, rumbling, soot and a red lamp blinking in the dark. It sounds like a horror film, but usually it is the burner telling you it needs a service. Here are six classic ghosts and what typically lies behind them.
1. 👻 Humming and whining from the burner
A burner that suddenly makes more noise than usual often has an oil supply problem. Typical causes are a blocked oil filter, air in the oil line or a worn oil pump. The pump works harder when it cannot get enough oil, and you can hear it.
Check: oil filter, oil hoses and pump pressure and vacuum.
2. 💨 Rumbling and pulsation at start-up
If the burner starts with a bang or a rumble that makes the boiler vibrate, the oil-air mixture is rarely right in the first second. It can be caused by a worn or wrong nozzle, incorrect air setting or ignition electrodes that are misaligned or worn, so ignition comes too late.
Check: nozzle, ignition electrodes, ignition transformer and air setting.
3. 🖤 Soot and black smoke
Soot in the boiler and black smoke from the chimney are signs of incomplete combustion. The burner uses more oil than it should, and the soot forms an insulating layer in the boiler, reducing efficiency. The cause is often a worn nozzle, a dirty burner head or incorrect adjustment.
Check: nozzle, burner head and flue gas analysis. The boiler needs cleaning.
4. 👃 Smell of oil or smoke
If the boiler room smells of oil, there may be a leak at the pump, hoses or filter. If it smells of smoke, the flue may be partly blocked or the burner ignites too late. This is the ghost you must not ignore. A smell of smoke can mean combustion gases are escaping into the house.
Check: switch off the system and have it serviced by a professional as soon as possible.
5. 🔴 The red lamp blinking in the dark
When the burner goes into lockout, the red lamp on the control box lights up. The burner has tried to start but has not detected a flame. Typical causes are a dirty or faulty photocell (flame sensor), lack of oil, a blocked nozzle or a control box that is failing.
Check: oil level, photocell, nozzle and control box. Keeps locking out after reset? Then it is time for a service. Do not keep pressing reset.
6. 🕯️ The burner that keeps starting and stopping
Short run times with many starts wear the burner and cause poor combustion. It can be caused by an incorrectly set boiler thermostat, a nozzle or burner that is too large for the house, or a faulty control box.
Check: boiler thermostat, nozzle size and burner output relative to the house.
Nothing to be scared of
Most ghosts in the boiler room disappear with an annual service and the right spare parts. Arne Nielsen A/S supplies spare parts for Oilon, Riello, Bentone and many other brands: nozzles, filters, pumps, ignition electrodes, photocells and control boxes.
Not sure which part the burner needs? Send a photo of the rating plate to info@arnenielsen.dk and we will find the right one.
Happy Halloween from all of us at Arne Nielsen A/S. 🎃
Graphic: Oilon.