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Electronic Ignition vs Standing Pilot - Modern gas furnaces use electronic ignition systems to light the burner’s 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
White Rodgers Electronic Ignition Module
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 | Electronic Ignition vs Standing Pilot
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 replacing 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 of 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 replacing. That can happen, especially when the gas valve for the standing pilot gas ignition system gets submerged underwater. Or it is located in moist spaces. Places where corrosive effects from moisture can occur on the gas valve. Gas valves are durable, but if submerged underwater or overly excessive moisture conditions, they will corrode. That is the case, with most metals or any gas valve will, in conditions of that nature.
Time-Tested Reliability | Electronic Ignition vs Standing Pilot
The standing pilot gas valve, the thermocouple, and the thermopile are all time-tested components. 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 proper maintenance, the standing pilot gas ignition systems are reliable for many years. Especially if proper and routine maintenance happens on these systems.
The downside to the standing pilot, gas ignition system, is they require a pilot light all the time to function. That 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, the standing pilot gas ignition system is a safe method of flame proving. 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. That causes the overall system to suffer when it comes to efficiency.
Electronic Ignition Systems | Electronic Ignition vs Standing Pilot
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 proves, the electronic ignition system turns the gas onto 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. 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 cleaning. The electronic ignition gas ignition system has been proven to be reliable and safe. It provides ignition 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. That 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. Therefore, 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
- A 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.
Conclusion
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
Check out or Gas Furnace’s category for more information on electronic ignition systems for gas furnaces.
Questions from our readers:
What is a standing pilot ignition system?
The thermocouple device, when heated, provides a small amount of voltage to a pilot solenoid valve. If the flame goes out, the voltage stops, and the pilot valve closes. That is a method of proving flame. With no safe method of proving a flame, it is possible to allow large volumes of gas into the area around the furnace. Thus the name, safety pilot.
What is a millivolt ignition system?
Can you convert a standing pilot ignition system to electronic ignition?
Yes, you can convert those systems. We have covered this in another article. How to convert standing pilot to electronic ignition.
Electronic Ignition vs Standing Pilot
Thank you for this discussion! I live in the PNW where power outages of 1/2 – 7 days are common during cold winter storms. I have two free standing zone LPG stoves with SPI (Sherwood Industries EG40 & Avalon Avanti & circa 2012) for ambience and to supplement 4T elect heat pump. Once lit, the two active pilots together consume about 1.7 gpd which means refilling a modest 120 gal tank every three months (during peak demand pricing!) without ever turning on the burners. LNG terminates 1 mile from our neighborhood b/c the provider will not run a main supply line to individual utility drops until 24 of 26 homeowners agree in advance to service – unlikely since fewer than 8 have convertible LPG, some have wood-burning stoves/fireplaces and are wary of gas safety (I know…), and increasingly, many are looking to solar PV/Thermal as Washington offers rebates and net metering options. The only downside to converting to electronic ignition systems seems to be periods without power which then take out the heat pump and the LPG backups. Davide on November 1, 2018 at 5:53 am suggested D-cell battery sourced electronic pilot ignition for “naturally vented boilers”. Is there any product available or movement in the industry for a conventional electronic pilot ignition free standing, naturally vented stove system which is battery operated or otherwise compatible for short term (up to a week) with alternative battery power back up? I could also conceive of a single solar PV panel and storage battery as another alternative electrical source when power service is interrupted – potentially, a simple solution for emergency LED lighting and EPI heater starting. Thanks again for the informative discussion!
I have not heard of it but if you have that type of infrastructure (solar or some type of alternative off-grid power source) wiring the heater (electronic ignition) to your backup source should not be any different than wiring up a lighting circuit. I believe the electronic ignition would use less power than a lightbulb. It would have to run through an inverter for the DC to AC conversion but as long as there is juice from the batteries (other power sources) it would work.
Interesting discussion. However I would like to know if there are aftermarket kits to replace a spl with an electronic ignition. I have been replacing the themocouple on
a gas fireplace/ heater about every year. The latest one lasted 8 months. It is in my rental and as I had to be out of town at the time of the failure I had the gas supplier replace it at the cost of $140.00. I don’t yet have the bill so don’t know what brand of TC It had or what brand is in it now. do you have brand recommendations for replacements and or sources for conversions.
Thanks
Yes, you can find a conversion kit here
My 64 year old standing pilot furnace only needed ONE thermocouple replaced in 50 years of service so it is certainly far more reliable.
Adding dozens of components to accomplish the same purpose is simply creating a Rube Goldberg that will cost you far more money
in maintenance than it will ever save
You forgot to mention electronic ignition running on D-cells.
I vote for electronic ignition, now many ‘naturally vented’ boilers only requires 2 D cells to run the ignitor, and those cells will last years. So just have to get a couple of spare cells. It apply to, at least, tankless systems.
I’ve had three bids for replacing a wood-burning fireplace insert with gas insert. Two contractors won’t even talk about standing pilot lights except to say that they’re inefficient and not as safe. The old-school dude recommended a MV (milivolt) system with standing pilot light. He says the problem with IPI is that “in cold climates like ours (pacific northwest) can lead to a continuous pilot override, so the pilot still burns all season.” Wait, what? Also, a cold box and flue can lead to condensation on the window (IPI guys say this is “no big deal.”), also, if the “flames were on high setting during a previous use, and the flue is cold, there can be a backdraft, causing the unit to shut down for safety.” And, finally, “the pilot keeps the system warm and dry which reduces corrosion on the burner and heat exchanger.” So, are the contractors spinning the pros and cons of each system to match what they like to install?? Oh, the SPL system is about $1300 cheaper but has a smaller glass front. Still scratching my head on which is the better way to go… Be a luddite and go old-school? Or pay more $$, more electrical work, and go IPI???
Thank you for the helpful information, but there is too much missing for me to make a good decision. I live in a very mild climate where power outages are rare, so that is not a concern.
Standing Pilot and Electronic Ignition are both reliable and safe, but what does that mean? Do they fail at the same rate? Or are they both reliable but one fails every 5 years and the other usually last 10 or 15 years? Also, I know a thermocouple is cheap and easy to change, but how much does it cost to replace an electronic ignition, and can I easily do it myself or will I have to pay someone?
Finally, the electronic ignition is more efficient, but how much so? While I can’t find all the necessary info to compare accurately, two similar water heaters, one with E.I. & one with Standing Pilot, it seems that I may only save around $20/year in gas, but that is a 4-year payback on the extra cost for E.I., and I would expect the electricity cost to be pennies/year, but I don’t know that.
I’ll take your questions one at a time and thanks for the compliments:
Standing Pilot and Electronic Ignition are both reliable and safe, but what does that mean? Do they fail at the same rate? I don’t think there is anyone on planet Earth that can definitively answer that question. There are tons of variables such as environment, quality of gas, quality of power from your utility and other factors that affect that such as lightning storms. Thermocouples can fail because of a corrosive environment and electronic ignition can fail because of power surges. Additionally, because of the electronics, moisture and salty air can be a concern for the EI. Failure rates cannot be definitively determined but you can take precautions and have a standby so the failure is minimal. That means having spare parts in the event of a failure.
In my opinion, I prefer electronic ignition over a thermocouple for a few reasons. I’ve been on many service calls where the thermocouple was affected by 1) wind conditions blowing excessive drafts and extinguishing the pilot, garage doors opening and blowing out the thermocouple, thermocouple failure, blockage of the gas line by duct/dirt/debris preventing gas from getting to the pilot, and many other reasons.
While electronic ignition can fail I’ve observed over time, fewer problems with it than thermocouples. Just my opinion, it is far more reliable and less frustrating especially when it comes to taking a shower or having hot water in the house or even heat. It sucks getting up at 3 a.m. to relight a stubborn pilot light just to have heat.
As far as electronic ignition being more efficient, it does not use gas in the off cycle like a thermocouple does. That’s a pro now the con. If electronic ignition fails for whatever reason it costs more to repair/replace the module. A thermocouple costs around ~$10.00 while a new module/board if the module or board fails, can cost $50.00 or more. More for proprietary systems unless you have a warranty but even with warranties with most HVAC systems you still pay for labor to install it. I think power usage is very minimal for an electronic ignition system as the most power it will use will be when it starts which should only take a split second. So yes, pennies a year for power use.
As far as replacing a module or board yourself, that entirely depends on your skills and confidence. Every board and module is different in some way and sometimes it’s the little things that will get you so if you do replace it yourself make sure to pay attention to the details and read the instructions.
Hope this helps and enlightens you better along with other readers who want to know more.
Thank you. At least I know I don’t have any of the common causes for failure of either system at my house.
“Do they fail at the same rate?” That question is easy. No they do not fail at the same rate. The standing pilot has a much much better success rate than electronic ignition.
With the standing pilot you also have the added attraction of the boiler not condensating during the summer months, when not in use. The standing pilot burns off any moisture that would present itself if there was no flame present. During the summer when the boiler is cool, natural draft occurs through your boiler and out the chimney. This humid draft causes the boiler to condensate internally, which in turn leads to rust in the flue passages of the boiler, and inefficiency when in use. Standing Pilot wins at every turn.
Could I keep a spare elec. ignition on hand as I did with keeping a spare thermolcoupling on hand at my cabin? Would it be practical to do so? Could I change out the elec. ignition as easy as I did the thermocouple?
I am replacing a 27 yr old 65,000 btu Williams wall furnace with the same and see I have a choice between the two ignighters.
Thank you for any advice
Yes of course, however the part most common to fail will be the flame sensor. It won’t fail as much as it will need to be cleaned from time to time. Some use Emory cloth and some technicians even use a dollar bill. It won’t look unclean but a slight film gets on it and it will stop sensing the flame. It’s not a thermocouple BTW, its simply a piece of metal that acts as a conductor for the microamp the module needs to sense a flame. If you have power problems at the cabin, you may want a spare module in case a surge takes out the new one. Stay warm……….Caio!!
PS…..if you get a replacement make sure you get an exact replacement and if you ever have to change it do it wire for wire.
No mention of noise. Standing pilots are silent, I have not heard an ignitor yet that isn’t noisy.
Noise is negligible to minimal in my opinion. I’m thinking the whooshing sound from the main burners lighting is much higher than any clicking noise you get from electronic ignition. BTW, hot surface ignition is absolutely quite. Another thing, most furnaces, boilers, and water heaters are typically installed in places where a small clicking noise is not going to make a difference one way or the other.
Are there standing pilot units that do not require a chimney? We want to convert our oil furnace to gas direct vent, and I was hoping to replace our water heater as well to be able to completely eliminate the need for our very old chimney. Now, I’m not sure if that means I can only have an electronic ignition unit … Thanks!
You can get the old chimney lined with a special liner made for gas appliances.
I had my chimney lined with stainless steel liner. But, I now am in need of replacing my gas boiler and after much research and several quotes have decided on a direct vented side wall high efficiency boiler. Problem is I also need to replace my standing pilot hot water heater and my town will not permit a hot water heater to vent in the size chimney liner without a boiler also venting in it. So- I’ve been told my options are to either replace the boiler with a conventional chimney vented less efficient boiler and replace the HW heater with a chimney vented model OR have both the boiler and HW heater replaced with direct vented ones. Going direct vent on both would mean a waste of almost $2,500 already spent on the chimney liner.
Does anyone know if there is a 40 gallon standing pilot HW heater available that is direct vent and doesn’t need the chimney?
Really interesting read about electronic ignition and standing pilot for burners. It’s good to know that electronic ignition gas ignition systems will only use energy when it’s needed, like for boilers and whatnot. I’m a bit interested to learn more about the design of these systems and how they are developed.
Thanks so much for visiting………there are many other articles here to help you learn more about HVAC.
I have had 3 water heaters in 6 years, all top brands and each one had the same problem, faulty thermopiles/thermocouples. I give up and am going with the cheapest possible water heater. If they are going to be disposable, why pay more. Sure, I can wait for a replacement and install it myself, or pay a plumber an amount equal to the cost of a new water heater, or replace it myself, but I am tired of the hassle. If I can find a free standing pilot model, I am going with that option.
thermocouples cost around 10 bucks and take approximately 30 minutes to change. If I purchase a water heater is really has nothing to do with the ignition system but rather the tank quality. The tank quality also has something to do with the anode rod and maintenance and your water quality. Some anode rods need to be replaced after 4 years while others last 10 years. 6 years is about the time when I replace mine along with annual draining of the water heater. I have a heat pump water heater so I don’t worry about any ignition issues. It works fine even when I have many overnight guests and demand is high for hot water. I simply turn it to hybrid mode with the push of a few buttons and it keeps up with demand. Normal household usage it meets demand quite well.
Thermocouples go bad for many reasons including oxidation and corrosion. Oxidation is an element of corrosion. It could be the quality of your gas and it could be environmental factors of where the water heater is installed but it really has nothing to do with the brand of water heater you are buying. You can test the water heater thermocouple to see if it is good or you can simple replace it every six years or so. I’ve seen thermocouples and thermophiles go bad on more frequent occurrences because they were located in bad places subject to the environmental conditions above. If I had a choice between electronic ignition or standing pilot I would likely choose the electronic ignition water heater. It really would depend on my location.
Standing pilot keeps condensation out of tank compared to power vent. The standing pilot water heaters last forever in comparison. Power vent natural gas you get almost exactly 6 years and rust out because of hot and cold in heat exchanger. The pilot keeps moisture out of heat exchanger.
Thank you for this informative website–you have just saved me ~$5,000 quoted for a retrofit of an ignition system to replace the standing pilot on my very old, huge Clipper furnace that runs like clockwork, but ‘wastes gas’ and could ’cause the house to fill with gas if the pilot ever blew out’. The furnace is in the family room, completely enclosed and accessed by a door which opens into the room. I don’t see how the pilot could ‘blow out’ with the door closed and only opening to the inside of the room, but I was told that sometimes unlikely things do happen and that electronic ignition is safer and won’t waste gas.
It is highly unlikely the house will fill up with gas if the pilot goes out as the thermocouple/thermopile will turn off the gas to the pilot if there is no heat from the pilot flame.
Also, in my area of the Oregon coast, it is cool and moist enough most of the year that the heat from the pilot will not be wasted, but will help heat the house and help keep the house a little dryer. Summertime, if it is warm enough, I may turn the gas off altogether.
gas can accumulate in places inside the home and once it reaches a certain point it becomes dangerous so even small leaks can be dangerous.
Is it true that, since 2012, only the electronic ignition system can be used in residential homes? My daughter just had a standing-pilot burner replaced, and the plumber replaced it with an electronic ignition one .. the reason being that they are not allowed to install the standing pilot anymore since 2012. I’m just interested since I am thinking of replacing mine and would want the same standing-pilot.
Not really sure about it because codes vary from region to region. You have to call the county or city code authorities and ask. Usually they are in the Permits and Inspections department but the name can be different.
I use the pilot system for 24/7 heat in my free standing propane stove. I run my fan 24/7. The pilot light (plus some passive heat via windows)heats my house during the “shoulder season” before and after the winter season. Burner may come ON in the morning to bring the temp up (as we get closer to winter)…but pilot light does the main work. Plus I get radiant heat even if the electricity goes off. Also, I feel safer if I go on vacation during the winter (power outages).
My pilot light and fan are off during the warm season.
I worry that an electronic system will cost me more for gas.
Another valid reason for a standing pilot gas ignition system over the electronic ignition system is that a standing pilot hydronic heat system will circulate hot water without a circulating pump if the boiler is lower than the radiant part of the system.(like a basement location)
Hot water is less dense than cold, so the system will circulate although not as efficiently as with a pump. If you live in an area with frequent power outages, you can still have heat without electricity if your system is designed for it.
C’mon Man! How about no electricity available at water heater to drive the electronics, or can it run off batteries? You left this critical fact out.
whether you have a hot water boiler or a forced air furnace you need electricity for the circulator pump or the blower. Of course water heaters and steam boilers are excluded from that unless the steam boiler utilizes a condensate pump. The issue you are speaking has been discussed in the water heaters pages so it has been covered. Because of your comment here this issue has now been covered on this page. Thanks!
A couple things. A thermocouple normally needs power applied to run the thermostat circuit if not the gas valve. A thermopile is a stack of thermocouples (two metals coupled) that together generate enough power to operate the solenoid in the gas valve and the stat. Also, there are many gravity hot water systems out there that were designed for no power. I own one. Being off grid with LP is a big use of thermocouples, as in camps or unwired outbuildings.
A thermocouple only powers the solenoid in a gas valve designed for a thermocouple and the rest of the system works on a 24 volt control circuit even through the thermostat. A thermopile can provide power though a thermostat and typically these are special thermostats designed to switch millivolt (actually milliamp) power that is provided by the thermopile. So you can have complete control power generated by a thermopile whereas you cannot do that with a thermocouple. It only provides millivolts though and nothing more. A thermopile puts out around 750 millivolts (for gas heating applications) while a thermocouple puts out around 20 to 24 millivolts give or take a little.
Rick
I have a gas stove. The oven has electronic igniter without a sensor, the igniter runs continuously when using the oven. I’ve replaced it 4 times. The worst is the electricity this little beast is consuming!
if you’ve replaced it four times then something is obviously wrong and needs to be corrected. Time to call in a professional.
I do not agree. I’ve had mine replaced 3 times now and all three service technicians said expect it to break every 3-4 years. So either the electric igniter is garbage, or the collective work ethic of heating professionals is garbage. Ten minutes of research online will show anyone looking that a standing pilot light is significantly more robust.
10 minutes of reading manufacturers instructions for PROPER installation of the hot surface igniter and it can last for the life of the equipment. Besides, hot surface igniters are not the only way to fire the main burners. There is direct spark ignition and intermittent pilot that is typically lit by a spark or a small hot surface igniter. Standing pilot does have its place and applications appropriate for certain circumstances but the electronic ignition also serves a good purpose in an appropriate setting. The article was written to help people decide which was best for them.
i want to convert back to standing pilot
because the furnace control module quit working
and people seem to think $200 is a fair price
and cant find a used one
this furnace is an older comfortmaker 80% efficient
but until that board puked it seemed to give more heat than my 95%
super efficient
a single part should not cost 1/3 to 1/2 the cost of a brand new furnace
The cost of labor is the bulk of the total price $200.00 per hour plus parts that is about average on L I, N Y
Here’s a vote for standing pilot. I was without electricity for 12 days during hurricane Sandy but my gas service which feeds my hot water heater and barbecue was not affected by the storm. I do have electronic ignition on my newer gas hydronic boiler for heating. The result was that I had gas for cooking (on the barbecue) and hot water heating but no gas for heat. Neighbors who had electronic ignition on their more efficient electronic ignition hot water heaters were stopping by often to borrow our shower. If you live in an area with frequent power outages, you may want to consider this.
Liking your comments about standing pilot. Same can happen during an ice storm (as it did for me in upstate New York) where the overhead power lines were taken down by weight of built up ice. Water heater worked but the electronic ignition on boiler was out of service till power was restored (which was 7 days later). In colder climates a good wood burning stove or fireplace can “save the day”. Of coarse there are always gasoline powered generators. That is another subject matter.
Thank you so much. I was about to buy a water heater with electronic ignition. Now I won’t. Where I live, we have power outages frequently. I have never been without hot water in all the years with my standing pilot hot water heater. And my husband has only had to re-light the pilot once in 10 years.