Valley winters are mild, which is exactly why heaters get ignored. Most systems sit unused from March to November, and then everyone turns the heat on during the same first cold night. A few minutes of checks now can save you a no-heat night and a rush-rate service call.
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Before the first cold night
- Test it early. Switch the thermostat to Heat and raise it a few degrees above the room temperature on a mild afternoon. You should feel warm air within a few minutes. Better to find a problem now than at 11 p.m. in December.
- Replace the air filter. A dirty filter makes your system work harder and can cause it to overheat and shut itself off.
- Check the thermostat. Put in fresh batteries if it uses them, and make sure the schedule matches your winter routine.
- Clear space around the furnace. In many Valley homes the furnace is in a garage, closet or attic. Keep boxes, paint, cleaning supplies and anything flammable well away from it.
- Open and clear the vents. Make sure supply vents and return grilles aren’t closed or blocked by furniture or rugs.
- Test your carbon monoxide alarms. California requires CO alarms in homes with gas appliances or an attached garage. Press the test button and replace batteries or old units.
Is that smell normal?
- A dusty, burning smell the first time you turn it on: usually normal. Dust burns off the heat exchanger or heating elements and should fade within an hour or so. If it doesn’t fade, turn the system off.
- An electrical or hot-plastic smell: turn the system off at the thermostat and call a pro.
- A rotten-egg or gas smell: don’t touch light switches or the thermostat. Get everyone outside, then call SoCalGas or 911 from outside.
Heat pump owners
Switch your system to Heat and test it the same way. In cold, damp weather you may see the outdoor unit stop and give off steam for a few minutes. That’s the normal defrost cycle. A solid block of ice that won’t clear is not normal. See our heat pump page for common problems.
Older homes with wall or floor furnaces
Many older Valley homes still heat with a wall furnace or a floor furnace in the hallway. Their grilles get very hot, so keep furniture, curtains and rugs away, and keep small children and pets from touching them. If the pilot light won’t stay lit or the flame looks yellow instead of blue, stop using it and have it checked.
When to call a pro
- The heater doesn’t come on, or it blows cold air
- It turns on and off every few minutes
- Your CO alarm goes off (get everyone outside first)
- You hear banging, squealing or grinding
- It’s been more than a year or two since a professional inspection
A yearly inspection is the best time to catch problems like a cracked heat exchanger, which can leak carbon monoxide. See what a maintenance visit includes, or read about common furnace problems.
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Call us and a real person will connect you with an independent, licensed heating contractor who serves your part of the San Fernando Valley. It’s free for homeowners.
Valley HVAC Network is a free referral service, not an HVAC contractor. All work is done by independent contractors licensed by the California CSLB. Learn how it works.
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