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HVACR 115- Gas Mechanical

HVACR 115- Gas Mechanical

Gas CodesGas Codes

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PIPING PLANS PIPING PLANS

• Authorities may require a piping sketch, including lengths, sizes and load demands.

• When adding to an existing system the line must be check to be sure they can handle the load.

• If not adequate the lines must be changed or a separate line installed.

• Authorities may require a piping sketch, including lengths, sizes and load demands.

• When adding to an existing system the line must be check to be sure they can handle the load.

• If not adequate the lines must be changed or a separate line installed.

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PIPING PLANS PIPING PLANS

• The point of delivery must be approved by the supplier.

• No gas lines supplied by two gas meters can be interconnected

• Back feeding to a meter that has been shut off is unsafe

• When interconnecting for stand-by fuels a back flow preventer must be installed

• The point of delivery must be approved by the supplier.

• No gas lines supplied by two gas meters can be interconnected

• Back feeding to a meter that has been shut off is unsafe

• When interconnecting for stand-by fuels a back flow preventer must be installed

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PRESSURE LIMITATIONS PRESSURE LIMITATIONS

• The maximum design pressure for piping inside a building shall not exceed 5 psig

• LPG maximum pressure is 20 psig liquid droplets will begin to form at higher pressures and temperatures as low as

-5(higher pressure and lower temperatures the gas will begin to condense)

• The maximum design pressure for piping inside a building shall not exceed 5 psig

• LPG maximum pressure is 20 psig liquid droplets will begin to form at higher pressures and temperatures as low as

-5(higher pressure and lower temperatures the gas will begin to condense)

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METERS METERS• Meters are sized for pressure and the

amount of gas with permissible pressure drop.

• Gas meters must be installed in a well ventilated area.

• They must be accessible for inspection, reading and maintenance

• Meters are sized for pressure and the amount of gas with permissible pressure drop.

• Gas meters must be installed in a well ventilated area.

• They must be accessible for inspection, reading and maintenance

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METERS METERS

• Meters can not be placed were they might be damaged (Driveways)

• Meters must be located at least 3ft away from a source of ignition

• Some electric meters can be a source of ignition. (relays, contactors)

• Meters can not be placed were they might be damaged (Driveways)

• Meters must be located at least 3ft away from a source of ignition

• Some electric meters can be a source of ignition. (relays, contactors)

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METERS METERS

• Meters must not be exposed to extreme or sudden temperature changes

• Gas meters must be supported by ridged pipe.

• Meters must be protected from high pressure, back pressure, or a vacuum

• Where a number of meters are installed, the meter should be tagged to identify the location being served by each meter

• Meters must not be exposed to extreme or sudden temperature changes

• Gas meters must be supported by ridged pipe.

• Meters must be protected from high pressure, back pressure, or a vacuum

• Where a number of meters are installed, the meter should be tagged to identify the location being served by each meter

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UNDERGROUND PIPING UNDERGROUND PIPING

• Clearance from all underground structure that might come in contact.

• The piping must be protected from damage by heavy vehicular traffic or digging

• The pipe must be buried at least 18” unless it not likely to be damaged then it must 12”

• Clearance from all underground structure that might come in contact.

• The piping must be protected from damage by heavy vehicular traffic or digging

• The pipe must be buried at least 18” unless it not likely to be damaged then it must 12”

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UNDERGROUND PIPING UNDERGROUND PIPING

• Some piping must be protected from freezing, consult the supplier for recommendations.

• Connections between plastic an metallic pipe must be made above ground.

• Plastic pipe must have a tracer wire or tape to allow locating of pipe after being buried.

• Some piping must be protected from freezing, consult the supplier for recommendations.

• Connections between plastic an metallic pipe must be made above ground.

• Plastic pipe must have a tracer wire or tape to allow locating of pipe after being buried.

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INSIDE PIPING INSIDE PIPING

• The pipe can not cause undue stress to the structure from its weight.

• Beams and joists can not be cut without permission from the building inspector.

• Gas piping can not pass through air ducts, dumbwaiters, elevator shafts or any place that will allow a gas leak to be spread throughout the building.

• The pipe can not cause undue stress to the structure from its weight.

• Beams and joists can not be cut without permission from the building inspector.

• Gas piping can not pass through air ducts, dumbwaiters, elevator shafts or any place that will allow a gas leak to be spread throughout the building.

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INSIDE PIPING INSIDE PIPING

• Proper supports and hangers must be used.

• If piping is to be removed the lines must be purged before cutting.

• Proper supports and hangers must be used.

• If piping is to be removed the lines must be purged before cutting.

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CONCEALED PIPING CONCEALED PIPING

• Concealed piping can not have unions or fittings that may leak.

• Tubing can be brazed or welded.

• Concealed piping can not be run through solid partitions without a chase ventilated to the proper location.

• Concealed piping can not have unions or fittings that may leak.

• Tubing can be brazed or welded.

• Concealed piping can not be run through solid partitions without a chase ventilated to the proper location.

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CONCEALED PIPING CONCEALED PIPING

• Tubing in partitions must be protected from piercing by nails or screws.

• The lines are protected with steel plates.• Piping in floors must be in channels that will

cause minimal damage to the building if the pipe must be exposed for repairs.

• Tubing in partitions must be protected from piercing by nails or screws.

• The lines are protected with steel plates.• Piping in floors must be in channels that will

cause minimal damage to the building if the pipe must be exposed for repairs.

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MISCELLANEOUS CODES MISCELLANEOUS CODES

• All branches must be capped or plugged after installation until equipment is installed

• A manual gas valve is required after gas regulators

• If two regulators are in series a valve between the 2 is needed

• All branches must be capped or plugged after installation until equipment is installed

• A manual gas valve is required after gas regulators

• If two regulators are in series a valve between the 2 is needed

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MISCELLANEOUS CODES MISCELLANEOUS CODES

• Gas valves must be accessible for operation.

• In a multi-tenant building there must be a manual valve for each tenant line.

• Emergency shutoff valves must be provided and plainly marked.

• Gas valves must be accessible for operation.

• In a multi-tenant building there must be a manual valve for each tenant line.

• Emergency shutoff valves must be provided and plainly marked.

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MISCELLANEOUS CODES MISCELLANEOUS CODES

• When gas equipment is installed in a garage the burner must be 18” off the floor

• When installing a gas unit in a repair garage the unit must be in a separate room with a 1 hour fire rating

• When gas equipment is installed in a garage the burner must be 18” off the floor

• When installing a gas unit in a repair garage the unit must be in a separate room with a 1 hour fire rating

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MISCELLANEOUS CODES MISCELLANEOUS CODES

• Combustion air must be taken from the outside.

• The heating room can not be used to store flammable materials.

• If overhead heaters are installed they must be at least 8’ from the floor.

• Combustion air must be taken from the outside.

• The heating room can not be used to store flammable materials.

• If overhead heaters are installed they must be at least 8’ from the floor.

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MISCELLANEOUS CODES MISCELLANEOUS CODES

• Equipment installed on the roof must have at least 6’ clearance from the edge of the roof.

• If 6’ is not provided guards at least 42” high must be installed

• Equipment installed on the roof must have at least 6’ clearance from the edge of the roof.

• If 6’ is not provided guards at least 42” high must be installed

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MISCELLANEOUS CODES MISCELLANEOUS CODES

• A 120v grounded outlet must be installed near the disconnect.

• The disconnect switch must be within sight of the unit.

• A 120v grounded outlet must be installed near the disconnect.

• The disconnect switch must be within sight of the unit.