Electronic Ignition vs Standing Pilot - Modern gas furnaces use electronic ignition systems to light the burners in modern furnaces. One can still purchase a gas furnace or water heater with the old standing pilot ignition systems. These systems have been proven reliable and safe over time. However, why would someone want to purchase a gas furnace or water with a standing pilot ignition system rather than purchase a gas furnace or water heater with an electronic ignition system? Let’s define the two different types of gas furnace or water heater ignition systems. Then we will surmise based on that why someone would purchase a standing pilot gas ignition system over an electronic ignition system.
Electronic Ignition vs Standing Pilot
Standing Pilot Gas Systems
Standing pilot ignition systems use a pilot light that is lit 24/7 to ignite the main burners. A standing pilot ignition system has a pilot light assembly and a thermocouple or thermopile. The two, thermocouple and thermopile are different but produce the same result. That is always proving the flame. The flame keeps the thermocouple or thermopile hot. When heat is applied to a thermocouple or thermopile they produce a very small amount of electrical current. That keeps a solenoid in the gas valve open via a pilot light that stays lit 24/7. If the fire or pilot light ever goes out on the thermocouple it stops producing this small amount of current. The valve in the gas valve closes preventing any gas from being delivered to the main burners. Sometimes it is the thermocouple however, sometimes it is something else that causes the pilot to go out. It can be something as simple as a breeze that blows the pilot out.
Thermocouples and Thermopiles
Most often if there is a problem with the standing pilot gas ignition system it is with the thermocouple or thermopile. These flame-proofing components need to be replaced when that happens. However, there are situations where the pilot gas line gets fouled or clogged with debris or trash. In that case, the blockage will not permit the proper amount if gas to the pilot tip. A thorough cleaning of the pilot assembly is in order in this situation. Once complete, they relight the pilot light and the furnace is returned to service. Simple enough and plenty of spare parts available when needed. Nearly every HVAC Tech and plumber carries thermocouples. Thermocouples are also available at most hardware stores. Or you can purchase a spare thermocouple here.
There are also those rare occasions when the gas valve goes bad and needs to be replaced. This can happen especially when the gas valve for the standing pilot gas ignition system gets submerged under water. Or it is located in moist spaces. Places where it is possible for corrosive effects from moisture to occur on the gas valve. Gas valves are durable but if submerged under water or to excessive moisture conditions they will corrode. That is the case, with most metals or any type of gas valve will, in conditions of that nature.
The standing pilot gas valve, the thermocouple, and the thermopile are all components that are time tested. They are reliable and effective to safely light the main burners of a gas furnace, boilers, or water heaters. While the standing pilot gas ignition systems are prone to problems with the proper maintenance the standing pilot gas ignition systems are reliable for many years. Especially if proper and routine maintenance is performed on these systems.
The downside to the standing pilot gas ignition system is they require a pilot light to be lit all the time to function. This means the standing pilot gas ignition system needs to use gas all the time. Another downside to the standing pilot gas ignition system is it adds heat to the system even in the summer. This will cause your air conditioner to work a little harder to remove the heat. The heat added by the continuously burning flame of the standing pilot light inside the furnace.
In conclusion for the standing pilot gas ignition system. The standing pilot gas ignition system is reliable and time tested with few problems. Especially with proper maintenance. The standing pilot ignition system is not as efficient as an electronic gas ignition system. It uses gas even during off cycles of the main burner. The standing pilot ignition system also adds heat to the system even in the summer. This causes the overall system to suffer slightly when it comes to efficiency.
Electronic Ignition Systems
Electronic Ignition has also been proven safe and reliable for igniting the main burners. Safe and reliable ignition for a gas furnace, water heater, or boiler system which uses gas. Electronic ignition only utilizes energy when the furnace, boiler, or water heater calls for heat. Most modern electronic ignition systems use direct ignition to the main burner. However, there are indirect electronic ignition systems that will automatically light a pilot. Once that pilot flame has been proven the electronic ignition system turns the gas on to the main burners. The pilot light can then light the main burners.
An electronic gas ignition system utilizes solid state controls for igniting the flame and proving the flame is lit. Electronic ignition gas systems do not use a thermocouple or thermopile to prove the flame. Electronic ignition gas ignition systems use a flame sensor that measures microamps to prove the flame. When the flame sensor becomes fouled it can prevent the proper amount of microamps from being read by the electronic control. In this case, the flame sensor needs to be cleaned. The electronic ignition gas ignition system has been proven to be reliable and safe. It is currently being used in many furnaces, boilers, and water heaters all over the world for gas ignition.
Electronic Ignition vs Standing Pilot - The Final Analysis
Electronic ignition gas ignition systems are more efficient than standing pilot gas ignition systems. The electronic ignition gas ignition systems utilize energy only when needed. These systems only utilize electronic ignition only on a call for heat or a call for the gas furnace, gas-fired boiler, or gas fired water heater to fire. This makes electronic ignition gas ignition systems more efficient than standing pilot systems.
After this the conclusion is that the electronic ignition gas ignition systems are more efficient and just as reliable as the standing pilot gas ignition system so why would anyone want to specify a gas furnace, gas-fired boiler, or water heater with standing pilot ignition when they can have a more efficient system with electronic ignition? We can only surmise but here are the possibilities:
- Cost – a standing pilot gas ignition system is cheaper versus the electronic ignition system
- Technical – the standing pilot gas ignition systems are easier to troubleshoot.
- Some people don’t want to try new technology. They have grown comfortable with the older and reliable standing pilot gas ignition systems
- Standing pilot requires no power to operate. The thermocouple or thermopile provides the power to the gas valve. When the power goes out you can still have hot water. Possibly heat but only if you have a steam boiler with a gravity fed condensate piping return for the boiler. If you have a standing pilot hot water boiler or furnace you are out of luck. Just as you would be for the electronic ignition under any circumstances for a power failure.
These are the possibilities. For those who prefer to have a standing pilot gas ignition system versus the electronic ignition gas systems. If you have other valid reasons why people select a less efficient but reliable standing pilot gas ignition system over an electronic system leave your comment below. Electronic Ignition vs Standing Pilot comments below this article.
Electronic Ignition vs Standing Pilot – Additional Resources
Additional resources for Electronic Ignition Systems and Standing Pilot can be found here.
Electronic Ignition vs Standing Pilot