How a Gas Log Safety Pilot Works
and how to light a gas log safety pilot.
For details about gas log burners read: Gas Log Burners and Safety Pilot Controls
How does a gas log safety pilot work?
Aside from the electronic ignition systems, the basic premise for the safety pilots used on gas logs is the same as those used for decades with wall heaters,
hot water heaters, and nameless other gas appliances.
How do you light a gas log safety pilot?
You turn the control knob to the pilot position, push the knob in, light the pilot with a match, then hold the knob down for 30 seconds or so until the pilot stays lit by itself. Once the pilot light
will stay lit on its own, you can then move the knob to the "On" position. For manually operated gas logs such as the one pictured to the right, this will turn the logs on. For remote controlled
gas logs, this will put the valve in the necessary position for the remote control to actuate the burner.
What if the pilot will not stay lit?
If you cannot get the pilot to light at all, meaning you hold the button down in the pilot position and hold a match up to the pilot and nothing happens,
then either the valve is bad or something is abstructing the gas from coming into or going through the valve. If you can get the pilot to light with a match, but it will not stay
lit on its own after holding down the knob for 30 seconds, then put the knob back into the off position, wait 5 minutes and try again. If it still will not light, then something is definately wrong and
you should have a professional check it out.
This page is not meant to be a trouble-shooting guide for gas logs, but in general, if you cannot get your safety pilot to stay lit, It could be that the pilot flame needs adjustment, the
thermocouple has gone bad and needs to be replaced, the entire valve has overheated and must be replaced, or something is abstructing the gas line. In any case, it is probably time to seek the assistance
of a professional. Any plumber or heating and air conditioning service man who deals with gas appliances with a safety pilot should be able to help you.
How does a safety pilot actually work?
Although most of us have learned how to light one of these things at some time or other, few of us have any idea as to how this ingenious little safety system actually works.
So here is a brief, but hopefully useful explanation of how gas log safety pilots work so you can decide if it is something that you want or need. You may also find this information
helpful for any other device that has a similar safety pilot.
Gas Logs that have a safety pilot have a valve body that is attached directly to the burner. This valve body that has 2 separate valves inside that control the gas:
The valve to the main burner and the valve to the pilot flame.
When the pilot is lit, the flame directly hits what is called a thermocouple (or thermopile).
The thermocouple is the ingenious device that makes the whole system work. The physical properties of the thermocouple are such that it actually generates electricity when there is a great
enough difference in temparature between the tip of the thermocouple and the base.
If the pilot flame is too hot, then the entire thermocouple gets hot and there is not enough temperature difference to create a current. If the pilot
flame is too low or not coming into direct contact with the thermocouple (or simply blown out), then there is not enough heat to generate a current.
This is why the proper adjustment of the pilot flame is necessary for gas appliances that have a safety pilot.
Now, on to how the pilot system works.
The electricity from the thermocouple is used to power an electromagnet that holds the pilot valve open, thus allowing the pilot to stay lit by itself. The amount of electricity needed
must be within a certain range of millivolts in order for this to happen. If there is not enough electricity (or no electricity) being generated,
then the electromagnet no longer functions and the pilot valve shuts. When you turn the knob to the pilot position and push it in, you are in fact manually opening the valve to the
pilot flame. Once the pilot gets the thermocouple hot enough, the electromagnet engages and keeps the valve open.
This is why you need to keep the knob depressed for about 30 seconds.
After the pilot is lit and stays lit on its own after releasing the pilot know, you can then turn the knob to the "ON" position.
With manually operated safety pilots, turning the knob to the on position
will light the logs and you can adjust the flame height using the control knob.
With remote controlled systems, turning the knob to the on position simply puts the main valve in a position to be opened and closed
buy whatever means the remote control uses. In the case of a remote controlled valve, some will have a battery operated device that opens and closes the valve to the main burner, thus turning the logs
on and off. More sophisticated systems (called variable flame remotes) will have a battery operated motor attached to the flame adjustment knob that will allow you to adjust the flame height as well.
The main burner valve is designed such that if the pilot valve is closed, no gas can flow through the main valve, even if you have it in the on position.
So as long as the pilot light is on and heating the thermocouple
properly, the system is operational and gas can then be allowed to pass through the main burner valve. If the pilot light gets turned off or blown out (or in some cases gets too hot),
then all valves are closed and no gas can pass through the system.
When the main burner is turned on, either by a remote controlled unit or by manually turning a knob, gas flows through the main valve and comes out the holes in the burner.
The flame from the safety pilot is positioned just above the first several holes in the main burner, so when gas flows out of the main burner and reaches the safety pilot, it automatically ignites.
So again, if the safety pilot is not lit (or for some reason the safety pilot gets blown out), the system automatically closes both valves so that no gas will
flow through either valve until the safety pilot is re-lit.
This prevents the system from allowing gas to flow freely into your home at any time in the event that the safety pilot blows out, or someone turns on the gas to your fireplace
without lighting it.
Have a Question About? Ask an Expert!
Answers to Recent Gas Logs Questions Posted To This Page
- Question #9369 - Posted: 1/28/2013 12:45:20 PM
Gas Logs Question
is there a way to purchase an electric igniter for our existing vent free gas logs that do not have a remote control?
Answer: In most cases you cannot add an electric igniter to an existing vent free gas log. Vent free gas logs have strict regulations and require that the valve and safety pilot be assembled and tested at the factory. So there is no way to do that in a field conversion. Are you looking for an electronic ignition system or just any type of system that can use a remote control...there is a big difference between them and electronic ignition is substantially more expensive than a standard remote safety pilot. Can you email me some pictures of what you have so I can offer further advice? Email pictures to: firstname.lastname@example.org
- Question #9367 - Posted: 1/11/2013 2:10:09 PM
Gas Logs Question
We have a log set (Napoleon) that was installed approx 3 months ago and we love it. However just today we went to turn it on and within 5-10 seconds the flame turns off. It ignites and then shuts down. Can you help?
Answer: I am sorry, we do not sell or offer support for Napoleon products. I would suggest that you contact the company that sold you the logs for help. As with most reputable gas log manufacturers, they require the seller to offer support for their products. If you cannot get help from the place where you purchased the logs, contact Napoleon directly to find an alternative. Here is a link to their contact page and dealer locator online:
- Question #9365 - Posted: 1/11/2013 1:56:03 PM
Gas Logs Question
I live in the Nashville area. Do you have any contacts here who can quote me to install a wood burning fireplace? I have no flue, have ventless. I hate it- I smell gas and no oxygen. My kids and I are too sensitive to it, but we LOVE fireplace ambiance. Thanks!
Answer: I cannot give you a contact to install a fireplace in your local area. I suggest you check the yellow pages to find a local fireplace shop. They are going to be the best resource for getting a new fireplace installed. You may also do well by referring to the resources available online at the National Fireplace Institute
- Question #9363 - Posted: 1/11/2013 1:35:30 PM
Gas Logs Question
I have 2 Buck Stove ventless fireplace log inserts and neither one wants to regulate by thermostat. When they are "on" they stay on and dont shut off until I flip the control box off. any idea how to make them work by temperature? Im pretty sure they are supposed to do that.
Answer: We do not sell or support products made by Buck Stove. I recommend that you contact Buck Stove customer service. They will most likely refer you to your nearest local dealer. Here is a link to their contact info: http://www.buckstove.com/contact.html
- Question #9362 - Posted: 1/11/2013 1:21:24 PM
Gas Logs Question
We have a ventless gas fireplace. It is located on an exterior wall of our brick home. The wall on the exterior is on our patio. What would be involved to convert it to vented? What do you think would be the approximate cost? Who should we call if it is a reasonable thing to do? Thanks very much.
Answer: For starters, you cannot "convert" a ventless fireplace to a vented fireplace per-say. You must remove the existing ventless firebox and replace it with completely different type of fireplace that has a chimney or vent. My suggestion is to replace it with a wood burning fireplace. This allows you to burn either wood or gas logs. It is also best for resale value since it allows the potential buyer the same options.
As far as the cost...it is all over the place depending on what you decide to do. You should have a local professional to come to your home and give you an estimate. When I sold fireplaces at a retail fireplace shop, the final cost including installation ranged anywhere from $7,500 to $25,000 depending on the complexity of the installation and the finished appearance of the fireplace. We also sold simple to very elaborate hand carved fireplace mantels that could cost as much as $10,000 just for the mantel. So how the fireplace is finished has a huge impact on the cost. The bare minimum would just be a fireplace with no decorative surround...maybe just a brick or tile facing with some wood trim...for a total of about $7500 installed (that is a prefabricated wood burning fireplace with a metal chimney).
I would suggest visiting local fireplace shops. They should at least be able to get you started in the right direction. These are the options you will need to explore. I would suggest you do some research online about the differences between these:
B-Vent (natural vent) gas fireplaces
Direct Vent gas fireplaces
Zero Clearance wood buring fireplaces.
We do not sell fireplaces (although I did for many years in a local fireplace shop). We sell only the gas logs that go into an existing fireplace. So if you like the looks of the vented gas logs you see on our website, they would require you to have installed a wood burning fireplace with a gas line piped into it. Vented gas logs are much more for enjoyment and realism than for heat.
Here is a link to our vented gas logs:http://www.hansenwholesale.com/gas-logs/
You may also want to use the resources at the National Fireplace Institute website. You can find qualified fireplace installers in your area using their resource locator. Here is a link to their website:www.nficertified.org
- Question #9361 - Posted: 1/11/2013 1:18:05 PM
Gas Logs Question
How do the logs stack on the model G6-24N We are moving them to a new location and dont have a picture now as we purchesed them years ago.
Answer: G6-24N is not a model number that I recognize for a complete gas log set from R. H. Peterson. Is it a Peterson gas log set? If it is, the model number does not indicate which logs you have, although it could be just the burner. Can you email me some pictures of what you have...the burner and the logs...maybe I will recognize it. Email your pictures to: email@example.com
- Question #9359 - Posted: 1/5/2013 12:14:20 PM
Gas Logs Question
having trouble with ventless logs took them out lit system after awhile it just clicks off .
Answer: I suggest you have someone come out and service them...it is not something that the consumer is generally qualified to do or capable of doing. If you read the owners manual for your logs (if you have one), you will see what I mean. Gas log manufacturers recommend that you have your ventless gas logs serviced annually by a qualified technician who can make sure the pilot and main gas valve are properly calibrated, clean the burner system and make any other adjustments or repairs necessary to keep you ventless logs in a safe operating condition.
You can use this link on our site to locate a qualified technician in your area: Who Installs Gas Logs?
- Question #9358 - Posted: 1/5/2013 12:08:07 PM
Gas Logs Question
Does my vent free gas log set-fireplace need to be caliberated?
Do the fake logs need to be replaced periodically for reasons other than aesthetic?
Answer: Gas log manufacturers recommend that you have your ventless gas logs serviced annually by a qualified technician who can make sure the pilot and main gas valve are properly calibrated, clean the burner system and make any other adjustments or repairs necessary to keep you ventless logs in a safe operating condition.
You can use this link on our site to locate a qualified technician in your area: Who Installs and Services Gas Logs?
- Question #9356 - Posted: 1/5/2013 11:26:10 AM
Gas Logs Question
I recently bought a home with a Majestic MR42 insert.
Right now it has a propane hookup to it, with fake logs. I would like to remove the hookup, and burn wood, which (from what I can tell) the insert is rated to do. The flue and chimney venting looks to be in fine condition. Anything that I should be checking, before I do this?
Answer: The MR42 is certainly a wood burning fireplace, so you can simply remove the gas logs and cap off the gas line. Just make sure you do a pressure test with soapy water to make sure there are no leaks...or remove the propane hookup altogether. You should certainly have the fireplace inspected and cleaned by a certified chimney sweep before you burn wood in it. This should be done annually. The chimney sweep will also be capable of removing the gas logs and taking care of anything else that needs to be done in order to insure you can burn wood safely. If you can email me some pictures of your fireplace, I may have other suggestions regarding glass doors a screen or anything else you may need. Email pictures to: firstname.lastname@example.org
- Question #9355 - Posted: 1/5/2013 11:12:18 AM
Gas Logs Question
I just had a Peterson 18' Vent Free log set installed (G10 burner) in my prefab Majestic fireplace (circa 1987). After I cured them with the damper open, I tried them with it closed...and within 20 minutes the tile and dry wall above the firebox was so hot I was afraid of the wall catching fire and shut it off? When I called the installer they told me to come right in and suggested (somewhat anxiously) that I swith to vented logs at their expense? But THEY sold me the vent free...what gives?
Answer: When it comes to prefabricated fireplaces, ventless gas logs are only to be installed if the fireplace has been tested and approved for the application. The owners manual for the fireplace must stipulate that they are approved. There may also be limitations to the BTUs allow and in many cases, a special hood must be installed above the fireplace opening to divert the heat away from above the fireplace.
Because your fireplace is so old, it is not likely that it was ever tested and approved for use with ventless gas logs. If you had contacted us prior to purchasing your gas logs we would have tried to locate a copy of the owners manual for your fireplace online in order to determine if ventless logs were suitable. We would have told you NOT to purchase them if we could not determine their suitability.
It is a good thing that the place where you purchased the logs is willing to swap your log set out for a vented set at their expense. I can also see why they would be somewhat anxious to do so since they do not want to take on the liability of having your house burn down. So I would suggest you take them up on their offer, or get a refund and go elsewhere.
Can you email me some pictures of your fireplace? If so, include a closeup of the metal label that has the brand and model number. The label should be just inside the opening on either side or at the top. With the info on the label, I may be able to find the owners manual for you and get the exact specifications that you need in order to get to the bottom line...although it seems more likely to me that you should simply be burning vented gas logs. Email pictures to: email@example.com
For those reading this post, ventless gas logs CAN be installed in hand built masonry fireplaces that are capable of burning real wood. Here is a link to more information about Where Ventless Gas Logs Can Be Installed