HVAC Parts, Furnace Humidifiers, Hot Surface Ignitors
As a public service, we are publishing a Glossary and a Trouble shooting guide below to try to educate our clients before they even attempt to diagnose problems. Most of the following will be covered.
Hvac parts, Furnace parts, furnace humidifiers, Goodman furnace parts, heat pump parts, Aprilaire humidifier, Aprilaire humidifiers parts, Heil furnace parts, Bryant furnace parts, humidifier parts, furnace parts, gas valves, hot surface ignitors, hot surface ignitor, spark ignition controls, hot surface ignition, Rheem furnace parts, controls, standing pilots, thermostats, wireless thermostats, Totaline wireless thermostats, programmable, flush mount thermostat, programmable digital thermostats, mechanical thermostats, freeze stats, short cycle timers, hard start kits, run capacitors, start capacitors, carbon monoxide alarms, fan -limit controls, printed circuit boards, fan centers, relays, sequencers, switching relays, thermocouples, millivolt pilot generators, millivolt gas valves, roll out switches, flame sensors, heat pump controls, defrost controls, electric furnace parts, condensate pumps, electronic ignition modules, pilot burners, furnace blower motors, condenser motors, air handler motors, motor mount universal bracket, boiler zone valves, boiler circulator pumps, trane furnace parts, trane gas furnace parts
AIR CONDITIONING:
To add heat or remove temperature and humidity in the form of condensation and promote clean air in a building.
B.T.U:
British Thermal Unit, the quantity of heat required to raise one pound of water one degree in Fahrenheit.
BOILER: A piece of heating equipment which is used to heat water to a hot water condition or a steam condition, depending on the type of system. This hot water or steam then circulates throughout a building into baseboards or radiators.
BAROMETRIC DRAFT REGULATOR:
A part of the flue in an oil furnace used to control the "STACK" temperature of the flue. It is usually a weighted device which allows air into the flue as the need is required.
BURNER:
A part in the furnace where gas is injected into the heat exchanger along with the correct amount of combustion air for proper ignition and burning of the gases. Yearly service of this part should be done by a professional service technician.
CAPACITOR:
An electric device consisting of two or more conducting plates separated from one another by an insulating material and used to store an electrical charge. There are RUN capacitors and START capacitors.
CIRCUIT BOARD:
A laminated electrical board, usually fitted with electronic components used in furnaces, boilers, air handlers and condensers to control most of the functions of the equipment. Some of these boards also have relays on them.
COMBUSTION AIR:
The air that must be fed to the burners of a gas or oil fired furnace or package heat unit for safe combustion of the fuel. As an example: most basements will need combustion air "PIPES" to bring and return the correct amount of outside air into the furnace. Direct vent furnaces usually don't require this however.
COMPRESSOR:
A "PUMP" used in air conditioning systems and usually located in the CONDENSER to move a refrigerant through an EVAPORATOR and back to a CONDENSER. This compressor changes the temperature and state of the refrigerant if it is operating correctly. Located in the CONDENSER. This is the most expensive part of an air conditioning system to replace and should be "checked" yearly by a professional service technician.
CONDENSER:
The piece of equipment used to remove the heat that has already been removed from a building. Usually located at ground level, but can be mounted on a roof, but is almost always outdoors. There are some mostly older systems that have the condenser indoors and "DUCT" the unwanted heat outdoors.
CONDENSER COIL:
A series of aluminum or copper tubes with aluminum plates or spinney fins attached to them used to dissipate heat which the COMPRESSOR has removed from the building. Located in the CONDENSER.
CONDENSER MOTOR:
The motor which turns the condenser fan blade or wheel in the CONDENSER which removes heat from the CONDENSER COIL.
CONDENSATE PUMP:
A small pump used to pump the condensate water which was removed by the EVAPORATOR COIL.
CONTACTOR:
An electrical relay which controls the flow of electricity to different components in the system.
DISCONNECT BOX:
An electrical box used to shut off equipment for servicing. Some of these have fuses or circuit breakers in them.
DUCT BOARD:
A fiberglass sheet, usually used to to build plenums, trunks drops and sometimes ducts themselves in a typical building duct system.
DUCT TAPE:
Tape used to seal any air leaks in a system. They can be fabric or metal depending on the application.
DUCT WRAP:
An insulating fiberglass blanket wrapped around ductwork used to prevent the loss or gain of heat from or into the duct.
DUCTWORK:
A system used to move heated or cooled , filtered air through a building consisting of plenums, metal or flexible pipes. These are connected to such things as grilles, registers, boots and return drops. Plenums, trunks and drops may be constructed of sheet metal and or fiberglass duct board material.
EVAPORATOR COIL:
A series of aluminum or copper tubes usually covered with aluminum plates, used to remove heat and humidity as condensation in a cooling system. This part is usually mounted above or below the blower in a furnace or air handler and is an integral part of a package unit. There is a condensate drain attached to the coil and run to a floor drain, directly outdoors or to a condensate pump.
FAN CENTER:
An electrical control box consisting of a transformer and a relay used to be a connection point of the thermostat wires and to the furnace and condenser. It has the function of telling the various components within the system to open or close their operation. Primarily used on older furnaces as this function is now controlled from the CIRCUIT BOARD in newer furnaces.
FLUE:
A pipe or series of pipes used on a gas or oil furnace, fireplace or any other fossil fuel burning piece of heating equipment. This flue is connected to the heat exchanger and must be kept clean and in good condition.
GAS VALVE:
An electro/mechanical device used in a gas furnace or package heating unit. This device opens and closes on command of the building thermostat to inject gas into the heat exchanger through the burners.
IGNITION CONTROL:
The control in a gas or oil fired piece of equipment used to start the actual ignition within the gas furnace heat exchanger or oil furnace fire box.
INDOOR AIR BLOWER:
A motor driven wheel used to circulate or move air through a duct system.
INDUCER BLOWER:
A motor driven small wheel used to move air and gases through a heat exchanger.
HEAT EXCHANGER:
The metal enclosure in a gas furnace or oil furnace or package heating system where the gas or oil is burned. The air from the building is circulated around this enclosure and picks up heat to be sent to the occupied space through ductwork. In NO WAY can there be a connection between these gases that are burned and the air being delivered to the occupied space as carbon monoxide poisoning and death can be the result. A yearly check of your heating system should be done by a professional service technician.
HEATING:
To raise the temperature in a building by burning fossil fuels such as liquefied petroleum, natural gas, refrigeration, or with electricity using gas furnaces, boilers, heat pumps, and package air conditioning.
HEAT PUMP:
A heating and air conditioning piece of equipment used to both HEAT and COOL a building. This really is a "Reverse Acting Air Conditioner". It is capable of reversing the flow of refrigerant in a cooling system, therefore, extracting heat from outdoors which is then brought to the indoor coil in the AIR HANDLER and distributed to the building through ductwork. Additional ELECTRIC HEAT STRIPS are added to the AIR HANDLER to help heat the building if the outdoor temperature is extremely low.
HOT SURFACE IGNITOR:
This is a ceramic/carbon element which glows red and is used to ignite the gas and air mixture coming out of the burners in a gas furnace. This device replaces the old "PILOT" which had to continually be burning gas to operate. Much more efficient!
HOT WATER HEATING:
To raise the temperature of domestic hot water usually through the use of a gas water heater , an electric water heater or a boiler.
LIMIT SWITCH:
The safety control used in a gas or oil furnace or an air handler to limit the "HIGH" temperature.
LINE SET:
The copper tubing connecting the EVAPORATOR COIL to the CONDENSER. Also called the refrigerant lines.
PACKAGE HEAT:
A self contained piece of equipment used to heat a building usually mounted on a roof of a commercial building or at ground level to which ductwork is connected and run to various parts of the building for heating purposes.
PRESSURE SWITCH:
A switch usually used within a gas or oil furnace which "Senses" low combustion or improper drafting of the flue gases and will shut the furnace down on safety.
PILOT:
A part in a gas furnace which has a small orifice and burns a small amount of gas used to ignite the burners in a gas furnace on a call for heat.
PRINTED CIRCUIT BOARD:
An electronic control which sends signals to all operations of a furnace, air handler, oil burner or air conditioning condenser.
SET BACK THERMOSTAT:
Also called an ELECTRONIC THERMOSTAT: A device used to monitor and adjust the building temperature and has set points which can be "PROGRAMMED" by the building owner to lower or raise the building temperature at given times. A great energy saver.
SWAMP COOLER:
Equipment which uses water sprayed over "pads" which then brings outside air into the building by means of ductwork or simply blown in through one central location. As the hot outside air passes over the wet pads the temperature of the air is reduced. No dehumidification takes place however.
THERMOCOUPLE:
A small tube filled with a material which generates a small amount of electricity and acts as a safety control within a gas furnace , gas water heater, gas boiler or a gas clothes dryer. This device is placed in the path of a burning pilot flame to sense that there is actually a pilot burning before the gas valve will allow gas to be sent to the burners.
THERMOSTAT:
An electric or electronic device used to regulate a control through the measurement of temperature.
Troubleshooting Gas Furnaces
Troubleshooting a furnace or air conditioner whether it be fired by gas, electricity or oil requires special tools, testing equipment and a host of other items. Since most people who are mechanically inclined may have some of this equipment there is the danger that they will think they can handle the job. To these people let me say up front, the author of this article is a Certified General Motors mechanic, but just as the automotive industry has added such things as air bags, computers, fuel injection, turbo chargers, superchargers and many other new components, so have the H.V.A.C. manufacturers. While you may have some of the equipment to test a vehicle, chances are you will only get just so far in troubleshooting the newer components. Then there is the chance of getting hurt as in the case of working on an air bag system not to mention damaging expensive parts from the lack of having the right testing equipment. New furnaces and air conditioners have the same issues. As an example, the newest type of refrigerant out in some air conditioners use R-410A refrigerant which has the possibility of running operating pressures into the 700 pound range. A brand new set of refrigerant gauges and hoses which are meant for the old refrigerants are only rated for about 650 pounds! All H.V.A.C. technicians have to buy new gauges and matching hoses not to mention new refrigerant recovery equipment as required by the E.P.A. If they don't, someone is going to get hurt for sure! We are writing this article only as a guide and strongly suggest that you call a reputable H.V.A.C. service professional to service your gas, electric or oil furnace and your gas, or electric heat pump or air conditioner.
So with all that said we will attempt to write this page with the emphasis on simple troubleshooting aimed at the average homeowner. If you are more mechanically inclined than this please bear with us as we will include more technical advise noted as " For Advanced Troubleshooting ".
FURNACES:
DESCRIPTION: Oil, natural gas, L.P.gas fired and electric strip heat.
All older gas furnaces since about 1985 usually have a pilot which burns all the time. This pilot burns and its flame must touch a sensing device called a thermocouple. The thermocouple generates a small amount of electricity within itself. Note: " For Advanced Troubleshooting " There are millivolt systems which use pilot generators that are totally different than the thermocouples used in standard 24 volt furnaces. The thermocouple can fail thus providing a safety against the furnace trying to send raw gas to the burners with no pilot present. If your pilot won't stay lit even though you have followed the pilot lighting instructions usually posted within the furnace burner compartment continue reading here. These instructions vary from furnace to furnace but usually amount to turning the gas valve knob to the pilot position, holding down on the gas valve knob ( sometimes a separate knob ) while lighting the pilot with a long match and then continuing holding down for (2) minutes. After this 2 minute hold down period release the knob. The pilot should remain lit. If it stays lit, turn the knob to the " ON " position. The burners should light if the power is on and the thermostat is calling for heat. If the pilot goes out immediately after you have held the knob down for (2) minutes you probably have a bad thermocouple. This is the number one call we get on these old furnaces. Be aware however, a bad gas valve or open high temperature limit control can sometimes cause similar reactions.
In oil furnaces this thermocouple is for the purposes of this article, replaced with a cad cell or flame eye which serves the same purpose as a thermocouple. If the oil and air mixture isn't ignited within 15 seconds the oil pump will shut down on safety. When this happens a reset button will pop up on the burner control box and must be reset." For Advanced Troubleshooting " Resetting this button multiple times will flood the fire box with raw oil and if ignition does take place there can be a serious fire or explosion!! There is no pilot on oil furnaces and no attempt to reach in the fire box with a lit match should EVER be made! Ignition in oil furnaces takes place by use of a high powered transformer and ignition electrodes." For Advanced Troubleshooting " These electrodes have a certain gap and angle that need to be set for proper ignition similar to spark plugs in a vehicle. Also oil furnaces have a pump which must develop 100 P.S.I. of pressure and an adjustable air venturi that must be adjusted to spray an atomized mist of oil and air at the right timing for correct ignition to take place AND within 15 seconds. As you can see there are many reasons to have an oil furnace cleaned and adjusted by a trained service professional before the heating season. Be sure there is a new oil filter in the oil supply line before the heating season and that you are using new oil that is not contaminated with water. An oil nozzle of the right size and spray pattern for the particular furnace should be changed along with the oil strainer on a routine tune up. We have seen many oil furnaces that were installed by homeowners or incompetent installers with NO oil filter in the supply line! Any air leaks in the oil lines will cause a loss of prime to the pump and result in no ignition within the 15 seconds required. We have seen many old oil systems with lines buried outside that, over time, develop leaks - Good Luck finding them. Every effort should be made to check the other possible problems out first before tearing up your lines. A good oil furnace service technician can locate leaks using a pressure gauge. One biggest suggestion from us is KEEP YOUR SYSTEM CLEAN. How well will your car run with gasoline that is 9 months old and full of water from sitting idle?
Furnaces over 1985 vintage:
If your gas has a small motor which you hear running ( not the main blower motor ) you most likely have a system that is loosely called an induced draft furnace. That small motor is supposed to be " inducing a draft through the furnace heat exchanger ". Usually this is the sequence of operation for these furnaces.
On a call for heat from the thermostat the first thing that happens is that small inducer motor runs. After a couple of minutes either a spark ignition takes place at an electronic pilot or a Hot Surface Ignitor begins to glow " Red ".
Once a burning pilot takes place or the ignitor glows red, a signal is then sent often times to a Printed Circuit Board ( Microprocessor ) or ( mini computer ). Then and only then, will the burners try to light. These printed circuit boards provide an extremely safe furnace in that if the furnace doesn't light in ( 3 ) tries it will go into lock out mode. To remove it from lock out turn the main power off to the furnace and right back on. This will reset it and it will try 3 more times to light. " For Advanced Troubleshooting " Spark ignition systems also have a gap that needs to be set correctly. Hot Surface Ignitors have a certain resistance value for each ignitor manufacturer. Printed circuit boards are very un forgiving as to improper grounding and polarity of the line voltage wiring to the furnace and can be damaged by power surges, lightning and improper testing! Some of these boards can cost a couple of hundred dollars depending on the brand and model of furnace so be VERY careful! We DO NOT suggest you get into this for safety and damage to the equipment reasons.
On any of these furnaces there are so many different parts and testing equipment necessary we require our own technicians to go to factory training classes on an on going basis.
AIR CONDITIONERS:
DESCRIPTION: 230 Volt central systems only.
Yearly preventative maintenance should include checking refrigerant, (freon) electrical controls, wiring, air filter in the furnace or air handler, belts if so equipped, oiling motors if needed, checking indoor and out door coils for good air flow ( cleanliness ) and operating amperage and refrigerant pressures. To answer the number one question we get from homeowners - no you can't pour freon into the system as you do oil into a vehicle and there is no dipstick as in a vehicle! The refrigerant is put into the system using special gauges, under high pressure used for the purpose, and outdoor temperature, ( has to be at least 65 degrees out side ) indoor conditions and specific " Charging " charts have to be used by qualified personnel to properly charge your system. Many times we are asked by people such as Apartment Maintenance people " What should the operating pressures be? " This can't be answered this simply as the outdoor temperature, humidity indoors and outdoors, ductwork, blower speed and a whole lot of other things must be considered. There are different refrigerants used and all require the use of gloves, safety glasses and other safety measures. Freon R22 boils at around -40 degrees. That's right it is boiling NOT freezing as most people think. If it comes into contact with your skin or even worse, your eyes - consider that part of your body badly burnt if not gone! Additionally there are serious penalties for venting refrigerants to the atmosphere imposed by the E.P.A. A Federal License is required to handle these refrigerants. " For Advanced Troubleshooting " Mixing of different refrigerants will result in damage to equipment as well as possible serious physical dangers!
HEAT PUMPS:
DESCRIPTION: Air source.
Service should be done at the beginning of the heating season and before the cooling season. The maintenance is much the same as for central air conditioners with many added controls to be "checked". Again, the single most important thing for a home owner to check is the furnace air filter. Filters need to be changed at least every 60 days during the heating and cooling season. Furnace heat exchangers, evaporator coils, motors and the compressor of your air conditioner all depend on a clean filter. Not to mention your utility bill will skyrocket with a dirty filter!
Heat pumps are basic air conditioners which have the capability of reversing the flow of refrigerant, thus they begin extracting heat from the air out doors to heat your home with. This reversing cycle takes place through your heat pump thermostat and a reversing valve within the heat pump. As the out door temperature gets colder the heat pump has less to work with and will begin kicking on the auxiliary heat strips or fossil fuel furnace to keep the indoor temperature at the desired point. About every 30 minutes during the winter, the reversing valve has to shift to the cooling mode to melt the ice that naturally builds up on the out door coil. This is known as the defrost cycle and takes place usually through another defrost Printed Circuit Board within the out door unit. The old heat pumps had to accomplish this through the use of pressure switches and relays. If the out door unit is not fully charged with " Freon " the only way your home will be heated is with your electric strip heaters or fossil fuel furnace which are very expensive to operate. If you have a high electric bill in the winter look at the heat pump as the prime suspect! The heat strips should only be coming on during the defrost cycle or unusually cold out door temperatures. Don't put the selector on your thermostat on " Emergency Heat " unless the heat pump has a problem. If you do, expect a high electric bill! If you see the Emergency Heat light on all the time you have a problem, call a service professional.
To answer common questions we often get - it is normal to see some ice on the outdoor unit. But it should go away when the reversing valve switches to defrost mode at which time you will hear a " swishing " noise on the out door unit. Then you will see steam rising as the unit melts the ice. This is normal and doesn't require calling the fire department as it is not on fire.
