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PLUMBING SYSTEM INSPECT DIAGNOSE REPAIR
AGE of PLUMBING MATERIALS & FIXTURES
AGE of CHIMNEYS & FIREPLACES
AGE of AIR CONDITIONERS & HEAT PUMPS
AGE of HEATERS, BOILERS, FURNACES
AGE of PIPING
AGE of WATER HEATERS
AIR DISCHARGE at FAUCETS, FIXTURES
AIR INLET VALVE, WATER TANK
AIR VOLUME CONTROLS, WATER TANK
ANTI SCALD VALVES
ANODES & DIP TUBES on WATER HEATERS
APPLIANCE EFFICIENCY RATINGS
AQUASTAT CONTROL Functions
BACKDRAFTING HEATING EQUIPMENT
BACKFLOW PREVENTER VALVE, HEATING SYS
BACKFLOW PREVENTER, HEATER WATER FEEDER
BACKUP PREVENTION, SEPTIC
BACKUP PREVENTION, SEWER LINE
BACKWATER VALVES, SEWER LINE
BOD WASTEWATER TEST
BLOCKED DRAIN REPAIR METHODS
BUILDING SAFETY HAZARDS GUIDE
CARBON MONOXIDE - CO
CHECK VALVES, WATER SUPPLY
CHEMICAL CONTAMINANTS in WATER
CHIMNEY INSPECTION DIAGNOSIS REPAIR
CHINESE DRYWALL HAZARDS
CHLORINE IN DRINKING WATER
CHLORINE IN SEPTIC WASTEWATER
CLEANOUTS, PLUMBING DRAIN
CLOGGED DRAIN DIAGNOSIS & REPAIR
CLOGGED SUPPLY PIPES, DIAGNOSIS
CLOGGED SUPPLY PIPES, REPAIR
CLOGGED SUPPLY PIPES, HOT WATER
CONDENSATION or SWEATING PIPES, TANKS
CROSS CONNECTIONS, PLUMBING
DEBRIS in WATER SUPPLY, Water Heater
DEPTH of DRAIN & SEWER PIPES
DEPTH of SEPTIC TANK
DIAELECTRIC PIPE FITTINGS
DRAIN & SEWER PIPING
DRAIN LINE DEPTH
DRAIN a WATER HEATER TANK
FLOOD DAMAGE ASSESSMENT, SAFETY & CLEANUP
FLOODED HEATING EQUIPMENT REPAIR
FLOODED SEPTIC SYSTEMS, REPAIR
FLOODED WATER HEATER REPAIR
FLOOR DRAIN / TRAP ODORS
FLUSHOMETER VALVES for TOILETS URINALS
GAS DETECTION INSTRUMENTS
GAS FIRED WATER HEATERS
GAS LP & Natural Gas Safety Hazards
GAS LP & Natural Gas Pressures
GAS PIPING, VALVES, CONTROLS
GALVANIC SCALE & METAL CORROSION
GALVANIZED STEEL PIPING
HARD WATER - SOFTENERS
HEAT TAPES, Heat, Insulation prevent Freeze-Up
LEAD POISONING HAZARDS GUIDE
LEAK TYPES, Water Supply/Drain Pipe
MANUALS & PARTS GUIDES - HVAC
METHANE GAS SOURCES
MIXING / ANTI-SCALD VALVES
MIX VALVE SCALD PROTECTION, Best Practices
MUNICIPAL WATER PRESSURE IMPROVEMENTS
MOLD INFORMATION CENTER
MVOCs & MOLDY MUSTY ODORS
NOISE / SOUND DIAGNOSIS & CURE
NOISE CONTROL for HEATING SYSTEMS
NOISE CONTROL for PLUMBING
NOISE, PLUMBING DRAIN DIAGNOSIS
NOISE, PLUMBING DRAIN REPAIR
NOISE, PLUMBING CHECKLIST
NOISE, WATER HEATER
NOISES, WATER PUMP
ODORS GASES SMELLS, DIAGNOSIS & CURE
ODORS IN WATER
ODORS, SEPTIC or SEWER
ODORS SEWER GAS in COLD WEATHER
ODORS, SULPHUR SMELL SOURCES
ODORS, URINE REMOVAL
OIL FIRED WATER HEATERS
OIL-FIRED BOILERS, HEATING
OIL FUEL TYPES & CHARACTERISTICS
OIL TANK PIPING & PIPING DEFECTS
OUTHOUSES & LATRINES
PIPING IN buildings, Clogs Leaks Types
PLASTIC PIPING ABS CPVC PB PEX PVC
PLASTIC PIPE INSTALLATION ERRORS
PLASTIC PIPE LEAK CAUSES
PLUMBING FIXTURES, KITCHEN, BATH
Plumbing Materials & Fixtures, Age, Types
PLUMBING NOISE CONTROL
PLUMBING VENT DEFINITIONS & CODES
PLUMBING VENT DEFECTS & NOISES
PUMPS, SEPTIC PUMPS
PUMPS, SEWAGE EJECTOR / GRINDER PUMPS
PUMPS, SUMP PUMPS
PUMPS, WATER PUMPS
PUMPS, WATER REPAIR
RELIEF VALVE LEAKS
REPAIR BURST LEAKY PIPES
SEWER GAS ODORS
SEWER LINE LEAKS & ODORS
SEWAGE BACKUP, WHAT TO DO
SEWER BACKUP PREVENTION
SEWAGE & SEPTIC CONTAMINANTS
SEWAGE CONTAMINATION in buildings
SEWAGE EJECTOR / GRINDER PUMPS
SEWAGE PATHOGENS in SEPTIC SLUDGE
SEWAGE PUMP CLOG DAMAGE
SEWER GAS ODORS
SEWER LINE REPLACEMENT
SHUTOFF VALVE LOCATION, USE
SOUND CONTROL for PLUMBING
SULPHUR & SEWER GAS SMELL SOURCES
SUMP PUMPS GUIDE
SWEATING (CONDENSATION) on PIPES, TANKS
TANK TYPES: WATER, OIL, EXPANSION, ALL
TANKLESS WATER HEATERS
Temperature Pressure Relief Valves - Water Heaters
TOILETS, INSPECT, INSTALL, REPAIR
TOILET FLUSHOMETER VALVES
TOILET INSTALLATION PROCEDURE
TOILET OVERFLOW EMERGENCY
TOILET PLUGS, SEWER BACKUP
TOILET REPAIR GUIDE
TOILET TISSUE CHOICES
Toilet Types, Flush Methods
TOILETS, DON'T FLUSH LIST
TRANSITE Pipe Water Supply Piping
TRAPS on PLUMBING FIXTURES
WATER CONTAMINANT LEVELS
WATER HAMMER NOISE DIAGNOSE & CURE
WATER HEATER SCALE - De-Liming Procedure
WATER ODORS, CAUSE CURE
WATER PIPES, Clogs Leaks Types
WATER PRESSURE & FLOW MEASUREMENT
WATER PRESSURE LOSS DIAGNOSIS & REPAIR
WATER PRESSURE PROBLEM DIAGNOSIS TABLE
WATER PRESSURE PUMP REPAIR GUIDE
WATER PUMPS, TANKS, TESTS, WELLS, REPAIRS
WATER PUMP REPAIR GUIDE
WATER QUALITY TESTS, CONTAMINANTS, TREATMENT
WATER QUANTITY IMPROVEMENT
WATER SHUTOFF VALVE LOCATION, USE
WATER SOFTENERS & CONDITIONERS
WATER SOURCE ALTERNATIVES
WATER SUPPLY & DRAIN PIPING
WATER TANK: USES, TROUBLESHOOTING
WATER TESTS, CONTAMINANTS, TREATMENT
WATER TESTING ADVICE
WATER TEST CHOICES & WATER TEST FEES
WATER TEST INTERPRETATION
WATER TREATMENT EQUIPMENT CHOICES
WELLS CISTERNS & SPRINGS
WINTERIZE A BUILDING
Propane & natural gas BTUs and gas pressures: Here we provide descriptions and photographs of unsafe gas piping, indications of unsafe or improperly operating gas appliances, gas meters, and other gas installation defects are provided. This document provides free sample draft home inspection report language for reporting defects in oil and gas piping at residential properties.
Green links show where you are. © Copyright 2013 InspectAPedia.com, All Rights Reserved. Author Daniel Friedman.
General safety warning: improper installation and even improper inspection and testing methods involving natural or "LP" gas can involve dangerous conditions and risk fire or explosion. If you smell gas you should leave the building immediately and should do so without doing anything that could create a spark such as operating a light switch or telephone. From a safe location, call your gas company's emergency line and/or your fire department. The text provided here is a working draft and may be incomplete or inaccurate.
How to calculate the BTU capacity of LP or natural gas fired equipment, heaters, or appliances
Computing BTUH: Technical Note: you can compute the BTU's per hour of gas consumption of your gas-fired equipment. Making sure than only a single gas appliance is running, watch the gas meter and measure the time required to use one cubic foot of gas. The formula: (3600 x 1000)/seconds = BTUH.
The number you compute for BTU capacity for an appliance should approximately equal the appliance's nameplate "input" BTUH on the appliance.
How many BTU's are in a cubic foot of natural gas? How many BTUs are in a gallon of LP gas or propane?
How many cubic feet of natural gas or propane will a heating furnace or boiler consume per hour?
How to calculate the conversion of gallons of propane or natural gas to pounds or BTUs
One gallon of propane contains about 91,500 BTUs and weighs about 4.20 pounds. One pound of propane contains about 21,500 BTUs. Calculation details are below.
One gallon of LP-gas (propane or C3H8) weighs about 4.20 lbs (at 60 degF), contains about 8.66 cubic feet of gas vapor per pound (at 60 deg. F), burns at 3,595 degF in air, and requires 23.86 cubic feet of combustion air to burn properly. The numbers for butane gas (C4H10) are different.
One gallon of LP-gas composed of butane weighs about 4.81 lbs (at 60 degF), contains about 6.51 cubic feet of gas vapor per pound (at 60 deg. F), burns at 3,615 degF in air, and requires 31.02 cubic feet of combustion air to burn properly. [Metric equivalents of these amounts are available from the website author or from the LP Gas Service Handbook cited below.]
How to Convert cubic feet of natural gas to BTUs/hour: multiply cubic feet per hour by 1,020/cubic foot of natural gas to obtain BTUH.
What is pressure of natural gas and LP or "liquid petroleum" gas inside the gas tank?
There is some confusion, even among LP gas service technicians about just what is the pressure inside the gas containers they deliver to or fill at properties. Perhaps this is because the gas laws (see Boyle's Law discussed at this website, for example), explain that the vapor pressure of LP-gases varies as a function of temperature.
"Vapor pressure" is the force exerted by a gas, LP gas in this case, attempting to escape from a container (say by pressing on the container's interior surfaces, or exiting at a gas valve if the gas valve is opened and not regulated). Some typical vapor pressures of LP gas (propane) are given just below. These pressures vary in real life depending on the purity of the gas and the percentage mixture of propane and butane.
Butane is generally going to show a much lower vapor pressure in the container than propane. But you can see from the table that as outdoor temperature varies between zero and 80 deg.F., the pressure of LP gas in the outdoor tank varies widely, from about 28 psi to as much as 140 psi.
Since the temperature affects the vaporization rate of LP gas stored at a property, you can understand that your full LP tank will appear to "last longer" in warmer weather not just because your heating boiler is not drawing on the tank, but because of the higher outdoor temperature.
Source: "LP Gas Serviceman's Handbook", cited at references below.
What are the common operating pressures of natural gas and LP or "liquid petroleum" gas in the building gas piping and at the appliance?
The Common operating pressure for natural gas is 3.5" of water.
How much gas do various household appliances and systems use?
The following are approximate since there is a wide range in fuel usage rate among appliances and between conventional and "high efficiency" heating systems. But according to NFPA Pamphlet 54 and the LP Serviceman's handbook (cited below), common household gas appliances consume LP gas roughly at these rates:
Gas service people and installers, in deciding on the total LP gas load at a property, may use "standard cubic feet per hour" or SCFH which is calculated by adding up the total anticipated gas appliance load (in BTUs per hour) and dividing by 2488.
The total gas requirements at a building are used to determine the necessary distribution piping sizes as well as the gas tank size most appropriate.
Other LP Gas Characteristics
Frequently Asked Questions (FAQs)
Questions & answers or comments about LP (propane) or natural gas pressures and BTUs.
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Technical Reviewers & References
Related Topics, found near the top of this page suggest articles closely related to this one.