| Do you want to learn exactly why your heating | | | | burners are like the gas burner under a water pot |
| system burns more fuel than it should? Of course | | | | on a kitchen stove - they are open to the |
| you do, or you wouldn't have found this article. | | | | atmosphere. Water heaters, Furnaces and Boilers |
| Following are answers to the questions you have, | | | | utilize atmospheric and gun-type burners. Sealed |
| or ones you didn't know you had. I will explain (in | | | | Combustion burners are as their title implies, the |
| defined technical terms) how your heating system | | | | combustion process is sealed tightly from the |
| is likely to be costing more to heat your home or | | | | atmosphere in which they are installed, like a |
| commercial building than it should and what you | | | | basement, attic or closet. Sealed combustion |
| can do to reduce those costs. | | | | burners take their combustion air from the |
| Anyone who drives an automobile knows that | | | | outdoors through a plastic pipe and vent their |
| certain cars use less gas than others. The same is | | | | products of combustion to the outdoors through |
| true for heating equipment and like gas-guzzling | | | | a second pipe, usually made of PVC |
| SUVs, some heating systems consume enormous | | | | (polyvinylchloride) or stainless steel. Gun-type and |
| amounts of fuel. The difference between cars | | | | atmospheric burners generally vent to the |
| and heating systems is cars offer many benefits | | | | outdoors through a chimney or mechanical venting |
| beyond the primary one of transportation. Cars | | | | means, called a "power-venter". While |
| have performance, comfort and visual appeal, as | | | | Atmospheric burners are simple and inexpensive, |
| well as can be a status symbol. Heating systems | | | | Sealed Combustion burners are much more |
| are tucked away in a basement, attic or closet | | | | complex and expensive. Atmospheric burners are |
| and their operation and performance are a | | | | mid efficiency types, whereas Sealed Combustion |
| mystery to most not in the Heating, Ventilation, | | | | burners are high efficiency types. |
| Air Conditioning (HVAC) trade, and still a mystery | | | | 4. Combustion Chamber - A combustion chamber |
| to many in the trade - so-called, "professionals" (a | | | | or, simply, a chamber is almost always part and |
| term I use loosely throughout this article). | | | | parcel of heating appliances that utilize a gun-type |
| To clarify, I may interchange the acronym HVAC | | | | burner, and is internal to a furnace or boiler. Inside |
| for heating, and vice versa, but this article is | | | | the chamber is where the actual fire during |
| about heating systems, how they work and how | | | | combustion of fuels takes place. An observation |
| they often burn excessive amounts of "fuel" - | | | | door or window allows a technician partial view of |
| gas or oil. | | | | the combustion process inside the chamber. |
| Most building owners know how to set the | | | | 5. Boiler - A cast iron or steel heat-generating |
| thermostat, change air filters and check the fuel | | | | vessel that utilizes water as a heat transfer |
| level on their heating fuel tank gauge, but that is | | | | medium to warm a space to a desired |
| about the extent of their heating system | | | | temperature. Boilers incorporate a burner which |
| knowledge. Typically, building owners do not want | | | | facilitates the combustion of fuels. Boilers can |
| to know how their heating system works; it | | | | include a chamber, but don't always. |
| seems too complicated and futile. They prefer to | | | | 6. Furnace - A Furnace includes a burner, most |
| leave the technical aspects to the service | | | | likely a combustion chamber, a heat exchanger, a |
| personnel they have come to trust. Did I say | | | | blower or fan and has ducts connected to it. The |
| "trust"? There are many reasons to examine | | | | blower pulls "return air" from the conditioned |
| your trust for your heating service company, fuel | | | | space through a "return duct" and pushes it |
| supplier and General Contractor if you are having | | | | across the non-flue gas side of the heat |
| a new building constructed - residential or | | | | exchanger. Once the relatively cold return air |
| commercial. | | | | comes into contact with the very hot heat |
| For starters, do not assume that the professional | | | | exchanger, the moving air picks up heat and is |
| you hire to design, install, service or maintain your | | | | propelled toward the occupied space through the |
| heating system is qualified to make all the right | | | | supply duct and out diffusers and registers placed |
| decisions in those respective aspects of the | | | | in the rooms to be heated. For sake of |
| HVAC trade. Just as in most professions, heating | | | | reference, furnaces have replaceable air filters, |
| professionals are often types who could care less | | | | boilers do not. |
| about the quantity of fuel a heating system ends | | | | 7. Heat Exchanger - A device that transfers heat |
| up consuming and costing its owner; their | | | | from one medium (fire and flue gas) to that of |
| paycheck at the end of the week is more | | | | another. Flue gas contains heat which is |
| important to them. The majority of HVAC | | | | transferred through a steel, cast iron, aluminum or |
| tradesmen have never been to school to learn | | | | stainless steel barrier (prior to exiting the appliance |
| the innumerable facets of the interrelated | | | | and up the flue) into a heat transfer medium |
| technologies. Moreover, many have never finished | | | | separated by the heat exchanger barrier. For |
| high school! But let's not get personal. Mostly, | | | | sake of our discussion, air, water and steam are |
| tradesmen have gathered their knowledge | | | | the heat transfer mediums relevant to this article |
| through hands-on experience. Experience comes in | | | | that transfer the heat from combustion to space |
| two flavors: good and bad. If the | | | | in the building to be heated. |
| on-the-job-training has been with lousy 'teachers', | | | | 8. Conditioned Space - The space within a building |
| then the student will be a lousy apprentice and | | | | - residential or commercial - that is to be heated |
| graduate to becoming a hopelessly old dog | | | | or air conditioned. We will deal with heating a |
| incapable of learning new tricks. | | | | conditioned space in this article. |
| It's not only ignorance and bad attitude that have | | | | 9. Hydronics - Hot water or steam heating |
| a hand in your fuel-hungry heating appliance's | | | | technology. |
| performance, though I wish it were. Deliberate | | | | 10. Forced Hot Water (FHW) - FHW heating |
| sales of terribly inefficient heating equipment plays | | | | systems include boilers (or sometimes water |
| a huge role. Sadly to say, American made boilers | | | | heaters) connected by pipes to heating "terminal |
| and furnaces are among the least efficient in the | | | | units" like radiators, baseboard convectors, hot |
| world and continued sales of them guarantee that | | | | water coils in an airstream and radiant floor |
| fuel companies will find you to be a better | | | | heating tubes embedded in floors. Forced hot |
| customer - you will buy more fuel! Greed will | | | | water systems succeed gravity hot water (GHW) |
| often lead to corruption, with most of the corrupt | | | | systems that were coal fired back in the day of |
| getting away with it. This is a significant reason | | | | their popular use. Water is heated in a boiler and is |
| for my writing this expose. | | | | then circulated, or forced with a 'pump' through |
| I have no specific desire to be confrontational | | | | pipes connecting the boiler to the terminal units |
| with specific companies, though I know them well, | | | | where heat is rejected to the space to be |
| but I can't close my eyes any longer, knowing | | | | conditioned. The hot water temperature is |
| that we are all heading toward a dead-end with | | | | lessened by the cooler room air that surrounds |
| our consumption of natural resources. Fossil fuels | | | | the terminal units and the water is returned to |
| are limited, they say the planet is heating up and | | | | the boiler to be reheated and re-circulated in a |
| polar bears' extinction in 50 years is all but | | | | continuous cycle that only stops when the room |
| inevitable. But the more we consume the more | | | | thermostat is satisfied by the increasingly heated |
| we strip forever from the planet its resources | | | | air. |
| and the little is left to meet the needs of its | | | | 11. Forced Hot Air (FHA) - As in FHW, a heat |
| inhabitants in the future. Must we consume until | | | | exchanger inside a furnace takes the heat |
| we've proved that the human species is the most | | | | generated by the combustion of fuel and |
| insidious parasite the planet has ever known? Do | | | | transfers it to the occupied space of a building, |
| we only take and put nothing back? At least we | | | | but through the passage of heated air inside |
| can take less of the fuel we use to heat our | | | | supply and return ducts. Forced Hot Air implies the |
| homes, businesses and industries and save money | | | | utilization of a furnace, whereas Forced Hot |
| as we do it. | | | | Water uses a boiler. |
| As a precursor to understanding how your | | | | 12. Steam - This system is the "Hydronic" cousin |
| heating system works, it is essential to | | | | of forced hot water. Both transfer heat through |
| understand the basic terms used in the industry, | | | | water or water vapor - steam. Both include |
| so let's start with the industry players, then we'll | | | | boilers that transfer heat from the fuel |
| move on to dispelling the mystery surrounding the | | | | combustion process to the heat transfer medium |
| more technical aspects. | | | | - water or steam. Both include pipes and terminal |
| Fuel Companies - "Fuel" is a general term I use to | | | | units. Steam is created when water in the boiler |
| cover any fossil fuel type such as, fuel oil, | | | | boils and converts to steam if it is continually |
| kerosene, natural and liquefied petroleum gas | | | | heated. Imagine a pot of water on a burner. The |
| (LPG), methane, butane and any other | | | | stove burner (gas or electric) heats the pot of |
| petroleum-based gas types that I may not have | | | | water above it. Left long enough above the heat, |
| listed here. Distributors of these fuels have one | | | | the water boils and vaporizes upward. In the boiler |
| goal: to sell ("market") as much fuel as they can, | | | | the vapor rises up in voluminous pipes onward to |
| to whoever will buy it and for the highest price. | | | | cast iron radiators or baseboard. Steam seeks |
| Period! They do not have your best economic | | | | equilibrium with the atmosphere. Hot vapor has |
| interests in mind. They are the well-known | | | | greater pressure than cooler air, so rushes for |
| petroleum giants, names emblazoned on tractor | | | | the nearest exit in a steam system into the |
| trailer tanks barreling down highways; large publicly | | | | lower pressure atmosphere in the conditioned |
| traded utilities and your local fuel company with | | | | space. Press the "Schrader" valve stem on your |
| warm 'friendly' ads in the media. Fuel companies | | | | car tire and high pressure air rushes out into the |
| have the most to gain by inefficiently designing, | | | | lower pressure atmosphere - it's the same with |
| installing and servicing your heating equipment. | | | | steam in a heating system. Strategically placed air |
| They want to deliver as much fuel at each | | | | vents on radiators and condensate return lines |
| delivery stop as possible. I know, I used to deliver | | | | allow the air above the water line in a steam |
| fuel when I worked for fuel companies in the | | | | system to be forced out of the system through |
| early 1980s. | | | | them, but stop as the steam comes into contact |
| HVAC Contractors - "HVAC" is a general term | | | | with their internal mechanisms. Steam is the least |
| that is often misused and misapplied. Businesses | | | | efficient heating type, as the water temperature |
| that go under this heading tend to get involved | | | | must be raised above 212 degrees Fahrenheit. |
| with the installation and service of many areas of | | | | Whereas, hot water systems water temperature |
| the indoor climate control realm, and it is a broad | | | | can be modulated based on the outdoor ambient |
| one! Not only does HVAC mean heating, | | | | air temperature. The warmer it is outside, the less |
| ventilation and air conditioning, but also humidity | | | | temperature is needed in forced hot water |
| control, indoor air quality and refrigeration. This | | | | system water. |
| player in the trade is likely to be more | | | | 13. Heat pumps, electrically heated boilers and |
| incompetent than fraudulent when it comes to | | | | baseboard element, wood and coal-fired boilers |
| accurately designing, installing and servicing heating | | | | and furnaces, solar and any other system types |
| equipment. | | | | not fired by petroleum products, are not included |
| Plumbing & Heating (P&H) Companies - Many | | | | in this article. |
| heating consumers are groomed through the ages | | | | 14. Limit Control - This control is also referred to |
| to believe that plumbers are the same as heating | | | | as an "aquastat" in FHW systems and a "Fan & |
| technicians - they are not. The only thing plumbing | | | | Limit Control in FHA systems. Hybrid hydronic |
| and heating have in common is in the way pipes | | | | systems - a steam boiler with a FHW loop (zone) |
| are connected - threaded, soldered (sweated), | | | | also incorporate Limit Controls. Limit controls can |
| welded, glued (cemented), and more recently, | | | | maintain low temperature and high temperature |
| compressed together with company specific | | | | thresholds in a heating system. Limit Controls |
| connection means. P & H types rarely have | | | | come in many different types and have a myriad |
| mastered heating technology. I can spot a | | | | of applications that require a specific type of Limit |
| plumber-installed heating system instantly. It's one | | | | Control. Limit Controls are often the device that |
| thing to be a master at piping, which many | | | | cause excessive fuel consumption and are |
| plumbers are, it's another issue altogether to | | | | selected for this reason by unethical fuel |
| know how the piped heating system works. | | | | companies so your system burns the maximum |
| Handyman - Knows a little bit more than a | | | | amount of fuel your heating system can possibly |
| homeowner about heating systems. | | | | burn. You will want to check the type of Limit |
| Heating Technicians - This is who you want to | | | | Control on your heating system! Read on to find |
| work on your heating system, but not necessarily | | | | out why. |
| one from a fuel company. Heating technicians | | | | 15. Nozzle - The device in an oil burner that |
| work for fuel companies and gas utilities/suppliers. | | | | meters a specific amount of fuel through it and |
| "Buyer beware!" Only half of these guys are | | | | converts the liquid fuel into a vapor that can be |
| qualified to do a good job on your system. Still, | | | | readily mixed with air and ignited. Nozzles have 3 |
| only 10% are really good, master-types who are | | | | means of categorization: the amount of fuel that |
| rarely stumped and who see the big picture - the | | | | passes through it in gallons per hour (GPH) @ 100 |
| original system design is clear to them, the | | | | pounds per square inch (PSI) of fuel pump |
| service history pops out like forensic science and | | | | pressure; the angle of oil vapor spray that comes |
| they can make your system work with little or | | | | out of its orifice; and the spray pattern - solid, |
| nothing to work with. | | | | hollow, or somewhere in between. Those |
| The aforementioned list is comprised of the | | | | specifications are written as an example like |
| standard players in the trade, but only fuel | | | | 1.00-80-B. This means 1 gallon of oil will pass |
| companies sell fuel, design, install and service | | | | through the nozzle at 100 PSI, 80 degrees is the |
| heating equipment, which is not to suggest that all | | | | vapor spray angle and "B" is code for solid. Too |
| fuel companies participate in all aspects of the | | | | high a GPH and your oil burner will over-fire your |
| heating trade, nor am I saying that all fuel | | | | furnace or boiler and start and stop too often - |
| companies defraud their customers, most do not. | | | | "short-cycle". |
| The case for burning less fuel can be easily made | | | | 16. Burner Orifice - Like in oil burners, gas burners |
| if everyone went out on the ocean in a boat and | | | | have metering devices and these are called |
| saw the sickening depth of pollution in our | | | | burner orifices or burner "spud". The wrong burner |
| atmosphere stretching across the water as far as | | | | orifice in a gas system can be deadly, as gas is |
| the eye can see. I live on the Atlantic side of the | | | | explosive and when it is not burned properly and |
| States and the prevailing winds blow off the land, | | | | in the correct proportion to air the outcome can |
| bringing with it the smog generated across the | | | | be inefficient and downright dangerous. Gas |
| country. Otherwise, watch a sunset and marvel at | | | | burners have at least one orifice but can have |
| the orange and red hues, for they are the result | | | | many, sometime too many, as you will see later |
| of pollutants and particulates in the atmosphere | | | | in this article. |
| that taint the natural color of sunlight. | | | | 17. Heat Loss Calculation - Software programs |
| Let us examine what goes into our atmosphere | | | | exist to accept data input relative to a building's |
| and our lungs when we breathe, when fossil fuels | | | | design characteristics like window and door types, |
| are burned. The byproducts of combustion of gas | | | | sizes and U-values, structure insulation R-values, |
| types and fuel oil include, but are not limited to: | | | | room sizes and internal heat gain like people and |
| 1. Flue Gas | | | | appliances. Once this information is entered into |
| 2. Carbon Dioxide | | | | the program the software calculates how many |
| 3. Nitrogen Oxide | | | | BTUs are needed on the coldest day of the year |
| 4. Nitrogen Dioxide | | | | to heat the building to a design temperature say, |
| 5. Sulphur Dioxide | | | | 68 degrees. There are no accurate short cuts to |
| 6. Soot | | | | a heat loss calculation. Anytime a new heating |
| 7. Carbon Monoxide | | | | system is designed it must first be preceded by |
| The exhausting of these compounds into the | | | | an accurate heat loss calculation. For everything |
| earth's atmosphere occurs constantly across the | | | | related to proper equipment and component sizing |
| globe and proportionately to the amount of fuel | | | | and selection is based on BTU generating and/or |
| burned by heating equipment, internal combustion | | | | carrying capacity. Pipe diameters are limited in |
| engines and industrial processes. The more fuel | | | | how many BTUs of energy they can transport |
| we burn, the more we contribute to the | | | | with water as its heat transfer medium, just as |
| aggregate pollution of our home - Earth. Why, | | | | duct sizes are limited in how many BTUs they can |
| then, burn more fuel than necessary? | | | | transport with air as the medium.Let's apply these |
| The following terms and definitions deal directly | | | | technical terms. For starters, let's create a |
| with heating system apparatus and components. | | | | scenario - you want to build a new house. The |
| | | | first thing you do is interview several building |
| 1. British Thermal Unit (BTU) - The amount of | | | | contractors who call themselves a General |
| energy required to raise one pound of water one | | | | Contractor (GC). A competent GC will give you a |
| degree Fahrenheit. British Thermal Units are | | | | package price for construction of all aspects and |
| expressed as a ratio to time -BTUs per hour | | | | systems in the new house. He will hire and |
| (written btus/hr., or MBH, where M=the Roman | | | | manage all subcontractors from the electrician, to |
| numeral for 1,000; B=BTUs; H=Hour, so | | | | the plumber to the roofer, and the HVAC |
| expressed as 1000s of btus/hr. All heating | | | | contractor. These tradesmen are subcontractors |
| equipment is rated in BTU heating capacity. A | | | | to the GC. The residential building trade is an |
| typical residential furnace has a heating capacity | | | | extremely competitive one and the profit margins |
| of 100,000 BTUs and can heat a 3,000 square | | | | are slim. The GC knows this, so hires the people |
| foot modern house. These are approximate | | | | he thinks will furnish acceptable quality at the |
| numbers, of course. For an accurate BTU | | | | lowest price. Unfortunately, most GCs are |
| requirement to heat a building a Heat Loss | | | | extremely unaware of the importance of proper |
| Calculation must be conducted (see definition for | | | | heating system design and the information that |
| Heat Loss Calculation). | | | | needs to be considered to produce the most |
| 2. Flue - The passageways that direct the | | | | efficient design for the money. He is also unaware |
| byproducts of combustion out of a heating | | | | of the requisite steps involved with cranking out a |
| appliance. | | | | professional design. It is the design that |
| 3. Burner - These come in many types, but we | | | | determines the cost. GCs often look at the cost |
| will restrict our discussion to Gun-Type, Sealed | | | | only. As long as the heating system "works", then |
| Combustion and Atmospheric, as these are most | | | | the GC is happy, even though he will never know |
| likely the kind that are in residential and | | | | that the system will consume a lot more fuel than |
| commercial buildings. Burners mix #2 fuel oil, | | | | if it was competently designed in the first place. In |
| kerosene, LPG or Natural gas with atmosphere | | | | fact, nobody will ever know that is, until a true |
| (air), then ignite and control the combustion of | | | | competent professional figures it out, but then it |
| their respective fuel types. Gun type burners can | | | | is usually too late. Most would rather spend more |
| be seen protruding from the fronts of boilers and | | | | money on fuel than replace the incorrectly |
| furnaces and burn gas and oil. Atmospheric gas | | | | designed system. |