On 2017-09-18 by Sam - diagnose improper gas burner flame
This is a problem that occurred about a month ago. I had the local gas company came out first and checked it and said that there is no gas leak from their end and it has to do with the unit itself and they cannot touch the boiler.
Wife called local boiler company and had a tech came out, took our money and left by saying that he does not know anything about this type of boiler.
Wife made second call to the local BUDERUS tech expert; tech came out and said that he himself cannot pinpoint the problem, took our money and said that the unit needs servicing (complete cleaning) and it will cost toooooo much for us to have him fix it
Honestly, I think that he himself didn't know what the problem is. He told my wife that "your husband can do that himself (after passing through my garage and seeing all my tools and equipment) because I see he is well verse in repairing different things".
When I came back home, I decided to take on the task myself. Lo and behold, after going through a series of troubleshooting, I determined that it was some of the burners that were not lighting and therefore causing the Raw Gas scent.
I have checked everything so far and cannot come up as to why it is doing that. I know for sure that all of the orifices are getting gas. I checked that by running the unit and wetting my finger to block off the orifices one at a time and feeling the gas on my fingers.
Fact: when I blocked off the orifices that the burners were off, the flames shot up much higher on the others that were lighting. When I blocked the ones that were lighting, ta-da, obviously the flames went out. Note: the flames are of a nice crisp blue color with NO yellow in them. Also, sometimes ALL the burners would light up when turned on.
When you say diagnostic, what do you mean? Do you mean it has to do with the settings, circuitry or control board etc.? I don't think so, because it is cycling through properly. I can put it on and off from the Logamatic R2107 control. This boiler produces domestic hot water also.
Finally, I was asked to check the inlet gas pressure and the pressure at the manifold, but I don't have a manometer to do that. All I can say is there is NO blockage, and I do see an increase in pressure when I block off one of the orifice. And, sometimes ALL burners light properly, so if there was a problem with the pressure, it should be off all the time (the burners that are not lighting). Would that be a reasonable assumption?
I still believe that there is insufficient oxygen coming in the chamber for four burners to achieve its stoichiometric point.
What are your thoughts on that?
On 2017-09-18 01:25:45.830096
by (mod) -
Is this a new problem or has this always been a problem - that might be diagnostic. Also has anyone checked the gas pressure?
On 2017-09-17 21:05:58.321128
Last comments are from me.
On 2017-09-17 21:05:03.376534
Thank you for your response. I have taken the system apart for service and did not find anything abnormal. Firstly, the system is a seal system and nothing (very doubtful anything) like spiders can get into that area that you mentioned.
Secondly, inside the combustion chamber was ABSOLUTELY CLEAN when I took it apart so much that I can literally eat food from inside the area if fallen inside. I mean it is that clean.
Thirdly, I checked all the orifices and burners properly and NONE of them were clogged or have absolutely NO signs of being clogged. I cleaned them out anyways. The burners are made of STAINLESS STEEL just to point that out. Even when the noted burner(s) are not lighting, the gas still flows through the orifice(s).
Only one or two burners may be out at a time and it's ONLY the same one(s).
To address your last suggestion of having a blocked shutter, this unit does not carry a shutter on it. Instead, it has an inducer fan which is located in the fan blower box. The fan comes on to rid the exhaust gas through the flue; however, I don't know if it also creates a vacuum or blow air for the intake air to get to the burner assembly. If it supposed to blow air, then I think that may be the problem at hand. Air does not blow through the d
Note: The motor works fine. This mo
I am stumped as to why the said burners would light sometimes and sometimes not. I would think that if something is really wrong with them, they would not light up at all.
Any other thoughts / suggestions on this are greatly appreciated.
by (mod) -
When some of the gas burner tubes ignite and others do not, I suspect that the burner gas metering orifice is plugged (spiders can do that as can debris) or that the actual flame orifices are clogged with rust and debris, or the air shutter is blocked.
This is a dangerous condition, risking ignition of a burst of unburned gas.
Your heating service tech would typically start with a visual inspection for obvious debris and dirt, clean the system, then test its operation again. IF the problem persists then she will look more deeply into parts like the gas orifice, air shutter, burner tubes.
Your separate suggestion of being air starved is an interesting one. I would think that you'd see improper combustion flame colour - more yellow, less blue, when the burners are ignited.
The system is in my opinion unsafe to use in this condition.
On 2017-09-17 by Sam
I have a Buderus Logano GA244 sealed gas fired boiler and not all of the burners are lighting up at all times. I was getting a strong scent of Raw Gas coming out from the unit. I determined that when some of the burners are off, that's when the smell appears.
The unit goes through the cycle properly without any hiccups. Gas is flowing through ALL orifices (4) when it is on but sometimes one or two burners would be off even though gas is flowing through them. Sometimes ALL four burners would light up. There is no problem with the ignitor nor the pilot; those are functioning properly
I think that when the unit is turned on and the burner closest to the pilot goes on, the flame is not JUMPING to the two outer burners sometimes. Important information to know: unit seems to work fairly good when the burner tray cover is off.
On the contrary, if cover is in place, sometimes they may not even want to light or if the unit is on while cover is off, and attempt to put on the cover, some of the burners would go off.
Overall, I think the unit is STARVING OF AIR.
What are your thoughts / feedback on this problem? Thanks.
can anyone go through the control sequence between louvered openings and the gas fired equipment?
soot problems after oil burner puffback
(Jan 6, 2015) mahgy said:
we had a furnace blow back a while ago, still noticing soot/black build up coming out of the heating vents on the walls.. this is a rental property. is this dangerous to our health? landlord does not seem concerned
No one can assess exposure levels of soot nor health risks accurately from a simple e-text, but in general, breathing soot is not healthy. If the heating system is no longer producing soot (which is itself unsafe) then the duct system may need cleaning.
Question: visible clues of adequate combustion air
(June 25, 2015) Anonymous said:
What if there is no visible combustion AIR
Anon you'd need to be more specific. Most building codes and standards discussing combustion air supply include a square-foot area size specification. For example if a heater of input BTUh amount X is in an open space of Z square feet then the area is deemed capable of providing adequate combustion air. Those guidelines presume a standard minimum rate of building air leakage or air exchange rate.
In the article above you can read details at the paragraph titled
Cubic Feet of Room Space as a Measure of Adequacy of Combustion Air: Total Input BTUH / 1000 x 50
Question: article correction
(Jan 14, 2016) Joe said:
With your cubic ft volume for adequate combustion air equation, you use 140 MBH for the total input BTU of a 180 MBH boiler and 40 MBH DHW. Should you be using 220 MBH total for that?
hanks Joe, we've corrected the math in the article above. I appreciate your careful reading. We can use all the editing help we can get.
Question: combustion air source for water heater in a trailer
(Mar 19, 2016) Anonymous said:
does combustion air for mobile home water heaters enter from under the trailer
In some installations it might;
Watch Out: if your water heater is gas or oil fired and lacks adequate combustion air the unit is unsafe and could kill the home's occupants.
21 June 2016 keith preddie said:
can anyone go through the control sequence between louvered openings and the gas fired equipment?
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Questions & answers or comments about combustion air requirements and safety hazards for oil and gas fired heating appliances
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American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) Handbook - Fundamentals, 1993, Chapter 15, page 15.9 Air For Combustion.
ASME CSD-1- Controls and Safety Devices for Automatically Fired Boilers, 1992 with addendum 1a 1993. section CG-260 Combustion Air.
BOCA - National Mechanical Code, 1990, article 10, Combustion Air.
NFPA 31 - Installation of Oil Burning Equipment, 1992, section 1-5 Air for Combustion and Ventilation.
NFPA 54: National Fuel Gas Code (2015), addresses heating appliance combstion air ventilation specifications. NFPA 54, ANSI Z223.1 provides minimum safety requirements for the design and installation of fuel gas piping systems in homes and other buildings.
NFPA 85: Boiler and Combustion Systems Hazards Code: NFPA 85 contributes to operating safety and prevents explosions and implosions in boilers with greater than 12.5 MMBTUH, pulverized fuel systems, and heat recovery steam generators.
NFPA 87: Recommended Practice for Fluid Heaters, This recommended practice provides safety guidance for fluid heaters and related equipment to minimize fire and explosion hazards that can endanger the fluid heater, the building, or personnel
SBCCI- Standard Mechanical Code, 1991, section 305 Combustion and Ventilation Air.
Axtman, William H., "Combustion Air Requirements: The Forgotten Element in Boiler Rooms", Grayh Gull Associates, retired executive director of the American Boiler Manufacturers Association, National Board Technical Series, Winter 1995 National Board Bulletin. Retrieved 26 January 2015, original source: http://www.nationalboard.org/index.aspx?pageID=164&ID=191
Excerpt: Several safety codes such as the National Fire Protection Association's standards, NFPA 54 - National Fuel Gas code, NFPA 31 - Installation of Oil Burning Equipment, and the American Society of Mechanical Engineers (ASME) CSD-l Controls and Safety Devices for Automatically Fired Boilers have sections covering the requirements for combustion air intakes. In addition, building codes such as the Building Officials and Code Administrators International (BOCA) National Mechanical Code and the Standard Mechanical Code published by the Southern Building Code Congress International (SBCCI) have air requirements for combustion. Editor's note: Some ASME Boiler and Pressure Vessel Code requirements may have changed because of advances in material technology and/or actual experience. The reader is cautioned to refer to the latest edition and addenda of the ASME Boiler and Pressure Vessel Code for current requirements.
Nussbaumer, Thomas. "Combustion and co-combustion of biomass: fundamentals, technologies, and primary measures for emission reduction." Energy & fuels 17, no. 6 (2003): 1510-1521.
Utiskul, Yunyong P., Wu, Neil P., Biteau, Hubert, "Combstion Air Requirements for Power Burner Appliances, Final Report", The Fire Protection Research Foundation, The Fire Protection Research Foundation
One Batterymarch Park
Quincy, MA, USA 02169-7471
http://www.nfpa.org/foundation, retrieved 25 Jan 2015, original source: http://www.nfpa.org/~/media/files/research/research%20foundation/rfcombustionairrequirements.ashx, Executive Summary: Gas-fired appliances require combustion air to properly function. Adequate air is necessary for
supporting combustion of the appliance burner, dilution of flue gas, and proper ventilation of the
space where the appliance is installed. Current standards and model codes outline requirements
and methods to supply the combustion air. One method is to provide outdoor combustion air
through openings or air ducts communicating with the outdoors through natural ventilation.
Most standards require the outdoor opening(s) be prescriptively sized based on the total energy
input rating of the appliance. However, in the United States, the current standards contain no
separate provisions to address the opening size supplying the combustion air for
commercial/industrial sized appliances, which typically have a high energy input rating of
greater than 300 kBtu/hr and are equipped with a power burner unit. As a result, the opening(s)
can be excessively sized when determined based on the current standards.
This research project establishes minimum outdoor combustion air requirements specific to gasfired
appliances utilizing power burners with input ratings no greater than 12.5 MBtu/hr. A
review of the available literature, engineering guidelines, and current standards and model codes
related to combustion air requirements was performed. This report provides an understanding
of the technical basis for the existing provisions for combustion air and their applicability to
power burner appliances. This report also identifies the range of energy input ratings for gasfired
appliances equipped with power burners, and compares the combustion air requirements
specified by a range of appliance manufacturers. A theoretical model for air flow through
openings was developed and the modeling results, together with the data gathered through the
literature review, were used to provide a baseline to establish the theorized combustion air
requirements suitable for power burner appliances.
 Jeff Wilcox, "Evaluating Duct Work, How to Evaluate Furnace Duct Work & Cure Short Cycling or Inadequate Ductwork Problems" Vermont Department for Children and Families, Office of Economic Opportunity, - dcf.vermont.gov/sites/dcf/files/pdf/oeo/WAPManual/AppendixI.pdf retrieved 12/5/2013. Geoff Wilcox
Vermont Office of Economic Opportunity
Weatherization Assistance Program
Reference Material for the original article came from:
1. Saturn Mechanical Systems Field Guide
2. Bacharach (Rudy Leatherman)
Field Controls provides instructions for the installation of LP and Natural Gas spill sensor switches, for example for their Gas Spillage Sensing Kit Model GSK-3, GSK-4, GSK-250M switches. Contact your heating service technician directly, or contact Field controls at fieldcontrols.com for more information. These switch models include a manual reset switch. Field Controls, Kingston NC 28504 - Tel 252-522-3031.
Tjernlund Products provides instructions for the installation and use of their controls, including the WHKE Millivolt Interlock Kit for use with their UC1 Universal Control, MAC1E or MAC4E auxiliary controls for gas fired equipment. This document also describes Tjernlund's recommended combustion air safety check which we recommended in this article. Contact Tjernlund Products at tjernlund.com or at 800-255-4208.
Bachrach Corporation, www.bachrach-training.com provides education for HVAC technicians. We found their web pages hanging during loading -01/2009. Readers may want to contact the company directly at: bacharach-inc.com or at 800-736-4666.
R.E. Prescott Company, a producer of other REPCO™ residential and industrial products as well as a provider of design-build engineering services is at 10 Railroad Avenue, Exeter, NH 03833. Tel: 603-722-04321 or 888-786-7482. Trish O'Keefe from Prescott informed us (10/7/2009) that their company had nothing to do with the failed Repco heating boilers discussed at InspectAPedia.com. She wrote:
Our company manufactures & distributes residential water treatment equipment, including our Repco line of conditioners. We have a plumbing & heating supply dept as well. We are mistaken for the Repco Boiler company on a regular basis, most frequently in Oct. and Nov.
Any information you could give me on the other Repco company would be appreciated. We've assumed it is no longer in business, and we'd like to know that for sure. Many callers want to know where to get replacement parts and I would be glad to direct them if I knew...plus there's always a chance they might be interested in a Crown Boiler instead
Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair
Domestic and Commercial Oil Burners, Charles H. Burkhardt, McGraw Hill Book Company, New York 3rd Ed 1969.
National Fuel Gas Code (Z223.1) $16.00 and National Fuel Gas Code Handbook (Z223.2) $47.00 American Gas Association (A.G.A.), 1515 Wilson Boulevard, Arlington, VA 22209 also available from National Fire Protection Association, Batterymarch Park, Quincy, MA 02269. Fundamentals of Gas Appliance Venting and Ventilation, 1985, American Gas Association Laboratories, Engineering Services Department. American Gas Association, 1515 Wilson Boulevard, Arlington, VA 22209. Catalog #XHO585. Reprinted 1989.
The Steam Book, 1984, Training and Education Department, Fluid Handling Division, ITT [probably out of print, possibly available from several home inspection supply companies] Fuel Oil and Oil Heat Magazine, October 1990, offers an update,
Principles of Steam Heating, $13.25 includes postage. Fuel oil & Oil Heat Magazine, 389 Passaic Ave., Fairfield, NJ 07004.
The Lost Art of Steam Heating, Dan Holohan, 516-579-3046 FAX
Principles of Steam Heating, Dan Holohan, technical editor of Fuel Oil and Oil Heat magazine, 389 Passaic Ave., Fairfield, NJ 07004 ($12.+1.25 postage/handling).
"Residential Hydronic (circulating hot water) Heating Systems", Instructional Technologies Institute, Inc., 145 "D" Grassy Plain St., Bethel, CT 06801 800/227-1663 [home inspection training material] 1987
"Warm Air Heating Systems". Instructional Technologies Institute, Inc., 145 "D" Grassy Plain St., Bethel, CT 06801 800/227-1663 [home inspection training material] 1987
Heating, Ventilating, and Air Conditioning Volume I, Heating Fundamentals,
Boilers, Boiler Conversions, James E. Brumbaugh, ISBN 0-672-23389-4 (v. 1) Volume II, Oil, Gas, and Coal Burners, Controls, Ducts, Piping, Valves, James E. Brumbaugh, ISBN 0-672-23390-7 (v. 2) Volume III, Radiant Heating, Water Heaters, Ventilation, Air Conditioning, Heat Pumps, Air Cleaners, James E. Brumbaugh, ISBN 0-672-23383-5 (v. 3) or ISBN 0-672-23380-0 (set) Special Sales Director, Macmillan Publishing Co., 866 Third Ave., New York, NY 10022. Macmillan Publishing Co., NY
Installation Guide for Residential Hydronic Heating Systems
Installation Guide #200, The Hydronics Institute, 35 Russo Place, Berkeley Heights, NJ 07922
The ABC's of Retention Head Oil Burners, National Association of Oil Heat Service Managers, TM 115, National Old Timers' Association of the Energy Industry, PO Box 168, Mineola, NY 11501. (Excellent tips on spotting problems on oil-fired heating equipment. Booklet.)
Carson, Dunlop & Associates Ltd., 120 Carlton Street Suite 407, Toronto ON M5A 4K2. Tel: (416) 964-9415 1-800-268-7070 Email: firstname.lastname@example.org. The firm provides professional home inspection services & home inspection education & publications. Alan Carson is a past president of ASHI, the American Society of Home Inspectors. Thanks to Alan Carson and Bob Dunlop, for permission for InspectAPedia to use text excerpts from The Home Reference Book & illustrations from The Illustrated Home. Carson Dunlop Associates' provides extensive home inspection education and report writing material.
The Illustrated Home illustrates construction details and building components, a reference for owners & inspectors. Special Offer: For a 5% discount on any number of copies of the Illustrated Home purchased as a single order Enter INSPECTAILL in the order payment page "Promo/Redemption" space.
TECHNICAL REFERENCE GUIDE to manufacturer's model and serial number information for heating and cooling equipment, useful for determining the age of heating boilers, furnaces, water heaters is provided by Carson Dunlop, Associates, Toronto - Carson Dunlop Weldon & Associates Special Offer: Carson Dunlop Associates offers InspectAPedia readers in the U.S.A. a 5% discount on any number of copies of the Technical Reference Guide purchased as a single order. Just enter INSPECTATRG in the order payment page "Promo/Redemption" space.
The Home Reference Book - the Encyclopedia of Homes, Carson Dunlop & Associates, Toronto, Ontario, 25th Ed., 2012, is a bound volume of more than 450 illustrated pages that assist home inspectors and home owners in the inspection and detection of problems on buildings. The text is intended as a reference guide to help building owners operate and maintain their home effectively. Field inspection worksheets are included at the back of the volume.
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Special Offer: Carson Dunlop Associates offers InspectAPedia readers in the U.S.A. a 5% discount on these courses: Enter INSPECTAHITP in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.
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