National Oilheat Research Alliance 17
Even with plugs in place, tanks can accumulate water
while in storage.
Storage
• When storing tanks prior to installation,
remove the thread protector inserts and
install threaded plugs to keep water out
• It’s best to store tanks indoors or in a
weatherproof enclosure
Receiving
• Before beginning an installation, always
check at the job site to be sure that the
tank has not been damaged during manufacturing
or shipping. If minor repairable
damage such as a small scratch is
found, it should be repaired according to
the manufacturer’s instructions before
installing the tank. If the damage affects
the integrity of the tank, the tank should
not be installed
• Be aware water can be present in a new
tank. Even with protective shipping
plugs in the threaded tappings, temperature
changes can create openings large
enough for air and water to enter the
tank. Be sure to remove water
and/or any other contaminants in
the tank before installation
Fill and Vent Piping
• Fill pipes and vent pipes must be minimum
schedule 40 wrought iron, steel or
brass. Galvanized pipe can be used for
above ground tank installations but is not
approved for use underground. NFPA 31
also allows “other piping that is part of
an engineered fuel storage system that is
listed to UL 180"
• Pipe fittings must be schedule 40 and
be either malleable iron, steel, stainless
steel or brass. The 2020 version of
NFPA 31 also lists “press connect type
Terminate fill and vent pipes 2 feet or more away
from any building opening, intake vent or electric meter…
+5 ft.
5 feet or more from any air inlet
for appliances or flue gas outlet.
Vent pipe should
always terminate
above the fill pipe.
ELECTRIC METER AIR INLET
+2 ft. Vent pipe
should always
terminate
above the fill
line
Terminate fill and vent pipes 2 feet or more away from
any building opening, intake vent or electric meter...
and 5 feet or more from any air inlet for appliances
or flue gas outlet.