What's the difference between millivolt and electronic ignition, and which is better for outage-prone mountain areas?
Millivolt uses a standing pilot that's always lit; the tiny voltage it generates opens the gas valve, so it needs no household power and lights in any outage. Electronic (intermittent) ignition sparks the pilot only when you call for flame — more efficient, no year-round pilot — but it needs electricity or battery backup to fire. For outage-prone mountain areas, millivolt or electronic-with-backup wins.
How each system lights
Millivolt ignition keeps a small pilot flame burning all the time. That flame heats a thermopile, which generates just enough millivolts to open the main gas valve when you call for fire — no household electricity anywhere in the loop.
Electronic ignition (also called intermittent, or IPI) skips the standing pilot: when you hit the switch, it sends a spark to light the pilot only when you want a flame, then shuts it all down after. Two different philosophies, same goal — a lit fireplace.
The outage tradeoff
This is where the mountains change the math. Millivolt needs no power, period — the grid can be down for a week and the fireplace lights every time, which is why it's the classic choice for backup heat.
Electronic ignition is more efficient day to day (no pilot burning gas around the clock in July) and easier to control, but out of the box it needs electricity to spark. The fix is battery backup — most modern electronic systems, including much of the Napoleon line, take batteries that fire the ignition when the power's out. Just confirm your unit actually has it.
Which to choose for WNC
For an outage-prone ridge or a cabin at the end of a long line, we lean toward reliability. Millivolt, or electronic-with-battery-backup, both give you power-optional heat — and Valor's millivolt radiant models go all the way, running with no circuit board at all through a full grid-down stretch.
If your area rarely loses power and you want efficiency and app-style control, electronic shines. After Helene, more of our customers are choosing the setup that lights no matter what. We'll match it to your home. Call (828) 545-0525.
Related questions
- Do gas logs still work when the power is out?
- Will a gas fireplace insert still put out heat during an outage if the blower can't run?
- Which types of fireplaces work without any electricity?
- Do fireplaces with electronic ignition have battery backup for power outages?
- Can a gas fireplace heat my house through a multi-day outage like the one after Hurricane Helene?
- Do I need a permit to install a gas fireplace or gas insert in Western North Carolina?
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