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margojean

Nov 25, 2006, 6:29 AM

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fireplace gas burners

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We are looking for someone in the Lakeside area who installs gas burners in fireplaces. Ours burns yellow, and we want a more efficient blue flame. Perhaps an adjustment of the air mix is all we need, but this also needs a technician. Anyone know a technician who can help us?
margojean

Papirex

Nov 25, 2006, 8:48 AM

Post #2 of 12 (2606 views)

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Re: [margojean] fireplace gas burners

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If the flame is burning yellow, it indicates incomplete combustion of the gas; you are wasting gas if the burner has a yellow color. If it burns with a blue color, it indicates complete combustion; there will be no wasted gas within the parameters of the efficiency of the burners. Most standard buners (not high efficiency burners) burn at 73% efficiency.

This is a simple adjustment to do in most cases. Without seeing your burners, I advise you to look at the end of your burners where the gas enters them. If you see a cap like device with butterfly wing shaped openings on it, loosen the retaining screw for it and rotate it to allow more air to enter the burner while the burner has a flame. Watch the color of the flame change, when it is as blue as possible. Tighten the retaining screw.

A yellow colored flame in most cases is not dangerous, just wasteful. In rare circumstances it can be dangerous if the unburned gases built up in the flue and are ignited, resulting in an explosion.

You most likely need an adjustment, not a new burner. I spent my life working as a process instrument control technician, and as a HVAC technician. I have made this adjustment many, many times.

Rex

"The supreme happiness of life is the conviction that we are loved" - Victor Hugo

margojean

Nov 25, 2006, 9:27 AM

Post #3 of 12 (2599 views)

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Re: [RexC] fireplace gas burners

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Thanks for the quick reply. Your diagnosis is exactly right. The problem here seems to be that there is no adjustment for the air mixture. There is just a pipe with holes in it. So that is why we think we need a new installation.
margojean

Papirex

Nov 25, 2006, 11:07 AM

Post #4 of 12 (2594 views)

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Re: [margojean] fireplace gas burners

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Margojean, without seeing your existing burner, I will have to agree with you that a new burner is probably your best option. If you do opt for a new burner, I would ask the installer to show you where the air adjustment for the burner flame is. That will possibly assure you that you will not be buying another one with no air adjustment point.

It is sometimes a good idea to look at other gas-fired devices in your home while the burner has a flame too, such as the water heater. The manufacturers do not test the air-flame mixture, they just place the device for the mixture control in the position that is most often OK, and is not necessarily the most efficient position as that must be done with a flame actually burning. The same procedure that I described in my previous post can be used to adjust the flame on water heaters, etc.

You can see the type of air adjustment I described previously on almost all water heaters, it is usually on the outside of the burner compartment. Make sure the air intake is free of dust, debris, dead insects etc. It might be a good idea as a last thing to try, to vacuum the air intake on your existing burner to be assured that it is not partially clogged.

There are a lot of other variables to consider too. I don’t know if the quality of propane produced in The Republic is uniformly produced. We used to have a lot of problems with the propane and butane produced and delivered in Northern California back in the fifties. We would occasionally need to take the valve out of a five-gallon propane tank and turn it upside down to drain it. We would usually get a pint or more of a thick green liquid out of them. (Soup for Godzilla?)

Your burner openings may be encrusted with a burned on residue from impurities in the gas used, which would also affect the efficiency of combustion. I doubt if many of the gas distributors here clean and test their tanks and other equipment on a regular schedule as is required in The United States.

A last thought is to make sure that combustion air can easily reach your burner intake. If you have installed glass fireplace doors, and not allowed for air to reach the burner intakes, that may be your problem, try leaving the doors open and see if the color of the flame changes.

Good luck, Rex
"The supreme happiness of life is the conviction that we are loved" - Victor Hugo

margojean

Nov 25, 2006, 12:03 PM

Post #5 of 12 (2583 views)

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Re: [RexC] fireplace gas burners

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Thanks Rex, I have passed all your advice on to my resident engineer.
margojean

esperanza

Nov 25, 2006, 1:04 PM

Post #6 of 12 (2578 views)

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Re: [RexC] fireplace gas burners

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Hi Rex, new question: my gas hot water heater comes on with a bang that sometimes blows the little door open--the little door that covers the pilot and heater flame. What do I need to do to fix this? Makes me nervous...

Thanks! How great that you are a gas resource.

Esperanza

http://www.mexicocooks.typepad.com

Papirex

Nov 25, 2006, 3:48 PM

Post #7 of 12 (2564 views)

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Re: [esperanza] fireplace gas burners

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Esperanza, without observing what is going on, I can just venture a couple of guesses. It may possibly be that your pilot flame is too low, allowing too much gas to enter the combustion chamber before it finally comes in contact with the pilot flame and ignites, resulting in the big bang you describe. Look at the pilot flame, it should be about 5/8” to 34” inch high.

If that is the cause, the pilot flame height can be adjusted. The adjustment point on most water heaters is outside the combustion area; usually it will be in a square control box on the side of the heater. There will be a small cover on it with a screwdriver slot on it, remove the cover with a screwdriver, you will find an adjustment screw under the cover. Adjust the flame height using a screwdriver; it usually will require a narrow bladed screwdriver to make the adjustment.

There are a couple of other possibilities. Your burner may be allowing too much gas to enter the combustion chamber before it is ignited. There can be a couple of causes for that to happen. The chief suspect would be the pressure reducer on your propane tank. You may need to have someone from your gas distributor check it; it may need to be adjusted or replaced. The gas should be reduced to about ¼ of an ounce of pressure before it enters any gas appliance.

If these adjustments don’t fix the problem, you may have an obstruction in the flue. You will need to take down the flue to see if anything is in it. If you do need to disassemble the flue, be sure to re-install it exactly as it was before you worked on it. Two fittings are critical on a flue. One of them is the rain hood on the top of the flue, which obviously is designed to keep rainwater from running down the flue and extinguishing the pilot flame.

The second fitting, which is critical to install, is called the “draft hood”. It fits right on top of the water heater. It is sort of bell shaped on the outside, inside; it has an inverted funnel shaped part with no hole in the middle. The purpose is for it is to disperse any wind that gets past the rain hood to prevent the pilot light from being blown out on a windy day.

The first house we lived in here had two water heaters. The untrained jerk that installed them left the draft hoods off of both of them. For most of the year I had to go outside every morning and re-light the pilot lights so we would have hot water to take our morning showers. More than once I got in the shower and found we had no hot water because of winds during the night, which had died down by morning.

I think he also removed the “dip tubes” from them. The dip tubes are inserted in the cold water inlet side (usually the right side) to assure that the cold incoming water goes to the bottom of the tank, and the hot water will rise to be used first. We never got water any hotter than lukewarm in that house, that’s why I am reasonably sure the dip tubes were removed. Removing the dip tubes also destroys any economy that an untrained workman thought he might achieve.

The dip tube and the draft hood come with every water heater and are integral parts that must be installed for the correct operation of a water heater.

Good luck, Rex
"The supreme happiness of life is the conviction that we are loved" - Victor Hugo

Ron Pickering W3FJW

Nov 25, 2006, 4:04 PM

Post #8 of 12 (2561 views)

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Re: [esperanza] fireplace gas burners

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And, if you make any adjustments with a screwdriver, do it in "1/16 or less" of a turn and note where you started. If no change in what you are looking at, be sure to return the screw adjustment to the position you started at. Then go on to the next adjustment if any. A good way to judge the distance you're turning is to put a small piece of electrical tape near the end like a little flag (1/8 th of an inch or so "flag")). That will give you a better visual reference.
Getting older and still not down here.

patricio_lintz

Nov 25, 2006, 5:44 PM

Post #9 of 12 (2547 views)

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Re: [RexC] fireplace gas burners

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Commonly used in the Chapala area are the calentador de paso water heaters. These are pass through heaters. No large tank to keep heated. Bad thing is that if you run the hot water too fast, it goes lukewarm and then cold.

I always turn off the pilot light after showering. Even a pilot light uses up a cylinder of gas faster than you might think. My cylinder usually lasts a couple of months in this mode of operation.

Papirex

Nov 25, 2006, 6:51 PM

Post #10 of 12 (2538 views)

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Re: [patricio_lintz] fireplace gas burners

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Patricio, each of the three houses we have lived in here in Cuernavaca has had a stationary gas tank. Each of them had a 300 litro capacity. They will usually last about three months between fillings; I usually had them refilled every two months or so, to be on the safe side. One time, one of them ran dry one day short of three months since it was last filled. We do have a gas fired clothes dryer which we use a lot, so our gas consumption may be higher than it is for some people.

When we lived in Mexico City, the house had two of the little 40 Kilo tanks. We always turned off the pilot light when we weren’t using any hot water there; the water heater was very convenient to get to on a patio.

Actually, the amount of gas consumed by a pilot light is negligible, unless it means changing one of those individual tanks more often. We recently went to The US for a visit. I was gone for over a month. Before we left, I had the stationary gas tank filled, and I turned off the gas to the burner in our water heater. I forgot about it, and I left the pilot light burning. When I returned, I checked the gas level in the tank; it might have been one width of the needle on the capacity gauge lower than when I left. The amount of gas used by the pilot light in 36 days was negligible.

The house in Mexico City is my suegra’s home. She lives with us now, so the house there is vacant about 28 days per month. We did have an instantaneous water heater installed in it a couple of years ago, and we always turn the gas off when it is not in use.

We have never had a problem with cold water coming out of any faucet or the shower there no matter how long we run the water. It sounds to me like yours might need some adjustments; they should deliver hot water constantly as long as the water is running if they are properly designed and installed. Instantaneous hot water heaters are nothing new. They have been in use in The US for several years.

Rex

"The supreme happiness of life is the conviction that we are loved" - Victor Hugo

Cynthia7

Nov 26, 2006, 4:49 PM

Post #11 of 12 (2501 views)

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Re: [RexC] fireplace gas burners

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My 75 year old neighbor had an instant hot water system in his house in Van Buren, Arkansas in the 1930"s...so they are not new. I am surprised that more people don't have the little heaters that go on the showerhead and heat the water at that point..I used one in Nicaragua in the 1950's and have seen them advertised lately. They work well for certain places.

Papirex

Nov 26, 2006, 8:02 PM

Post #12 of 12 (2479 views)

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Re: [Cynthia7] fireplace gas burners

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Yes Cynthia, they have been around for a long time. My ex-wife’s uncle had one in a weekend cabin he built in Lake County, California in 1937. I was the type called a “side arm” heater. It was attached to the side of the kitchen range. It was a wood burning range, so it wasn’t very instantaneous. You had to build a wood fire in the firebox, and wait a while before you had hot water; there was no tank though. They also made side arm water heaters for gas fueled kitchen ranges in those days; they were instantaneous.

The first instantaneous water heater I had was in a house I bought in Fairbanks, Alaska in 1976, the house was about five years old. It was integral with the water heater for the hot water heating system for the house. It operated independently of the home heating system though.

That type of instantaneous hot water heater is very common in Alaska, once you are away from the Anchorage area. The Anchorage area is the only area in Alaska with a piped natural gas supply. All other areas in the state primarily use heating oil for home heating fuel. Natural gas is much cheaper than heating oil; so many, not all, homes in the Anchorage area have conventional water heaters in them.

It is amazing how well instantaneous water heaters work up there. Almost everywhere in Alaska, water from the tap is 40° F. That is the same temperature as in the food compartment in a refrigerator. You’re wasting your money if you buy a refrigerator with an ice water dispenser up there, all you have to do is let the water run for a few moments, and you’ve got ice water. In all but the littlest towns and some villages it will be pure water.

The domestic water supply is so cold up there, that all newer homes have tempering valves to mix some hot water into the supply pipes for all the toilets. If they didn’t have them, there would always be water “sweating” off the sides of the toilet tanks and dripping on the floor, summer and winter.

I do think that instantaneous water heaters are a good idea to use down here, although the water pressure is so low in most homes here that not much water is used for showers. We are renting, so we will live with what we’ve got for now. Our water heater has a small tank, just 38 litros, that’s just a little over 10 US gallons. There are four of us in the house usually. We can take long showers one after another, and never come close to running out of hot water.

Rex

"The supreme happiness of life is the conviction that we are loved" - Victor Hugo