Quick Checks Before You Call
A surprising number of no-heat calls come down to something simple, so it is worth a two-minute walk-through. Check the thermostat first. Confirm it is set to heat, the target temperature is above the room temperature, and the batteries are fresh if it is a battery model. A blank or frozen thermostat will never call for heat.
Check the boiler has power. Make sure the service switch beside the boiler is on and that the dedicated breaker in your panel has not tripped. A tripped breaker can point to an electrical fault, so if it trips again immediately, leave it off and call us.
Check the system pressure gauge. Most Greater Vancouver boilers want to see roughly 1.0 to 1.5 bar when cold. If the needle is in the red or near zero, the boiler may lock out to protect itself. Low pressure is one of the most common reasons a boiler refuses to fire.
Reading the Fault Code or Lockout Light
Modern condensing boilers from brands like IBC, Navien, Rinnai, Viessmann, and Lochinvar display a fault code or flash a lockout light when they shut down. Note exactly what it shows before you do anything else. That code tells a technician whether you are dealing with ignition failure, a flame-sensing problem, low pressure, or a flue fault.
Many boilers allow one reset attempt. If yours has a reset button and the manual permits it, you may press it once. If the boiler lights and stays running, the fault may have been a one-off. If it locks out again, do not keep resetting it. Repeated resets on a unit that will not stay lit can pump unburnt gas into the combustion chamber and mask a genuine fault.
Write the code down and have it ready when you call 604-359-1081. It often lets us bring the right part on the first visit.
Common Causes of a Boiler That Won't Fire
Low water pressure tops the list. A slow leak, a recently bled radiator, or a tired expansion tank can drop pressure below the threshold the boiler needs to ignite. Re-pressurising via the filling loop sometimes restores heat, but if pressure falls again there is a leak to find.
Ignition and flame-sensing faults are next. A dirty flame sensor, worn ignition electrode, or faulty gas valve can stop the burner lighting or cause it to drop out seconds after firing. These are routine repairs for a gas fitter but not a DIY job.
No gas supply can be the issue if other gas appliances are also out, or if the gas isolation valve at the boiler was accidentally closed. Frozen condensate lines are another classic cause in a Vancouver cold snap, covered in our dedicated article. Finally, a failed circulator pump or a stuck diverter valve can leave the burner running while no heat reaches your rooms.
When It's an Emergency vs When It Can Wait
In our mild coastal climate, a single cold night rarely puts your plumbing at risk, so a boiler that simply will not fire is usually urgent rather than a life-safety emergency. Treat it as a true emergency, however, if there is also a gas smell, a carbon monoxide alarm sounding, or water leaking heavily. In those cases follow the safety steps for gas and CO situations, leave the home, and call FortisBC at 1-800-663-9911 or 911 before calling us.
Vulnerable households, including homes with infants, elderly residents, or anyone with health conditions, should treat any loss of heat as a priority even in mild weather. We offer same-day and weekend boiler service across Greater Vancouver for exactly these situations.
If the basic checks above have not restored your heat, the next step is a professional diagnosis. Call GasBoilers.ca at 604-359-1081 and we will get a Red Seal gas fitter to you quickly.