NFPA requires that a readily accessible fusible link
safety shutoff valve shall be installed:
1. At the outlet of an above ground tank
2. Within 6"of the filter inlet and inside the building
if the piping passes through a foundation
3. Within 12" of the inlet connection to the burner
National Oilheat Research Alliance 23
Chapter 5
Fuel Lines
Fuel lines bring fuel from the tank,
through a filter, to the fuel unit. All fuel line
connections must be tight and leak-proof and
all threaded connections should be joined
with non-hardening, fuel resistant pipe joint
compound. NORA recommends the use of
pipe joint compound that is rated for both fuel
oil and biodiesel, such as Loctite® 565
or equivalent.
General Recommendations
• Copper fuel supply (and return) lines
should be connected with flare fittings
and run from the tank to the burner
with as few splices and fittings as possible
• Fuel lines should be protected from
damage and properly secured
• Fuel lines that run outside of buildings
should be insulated to protect against
freezing
• All fuel line connections should be
installed where they will be visible
and accessible
• Whenever possible, each burner should
have its own fuel line
• All fuel lines that contact concrete or
soil should be protected in a continuous
run of corrosion resistant tubing.
Prior to 1990, many unprotected copper
fuel lines were installed under concrete.
NORA recommends customers upgrade
these lines
Materials
Fuel supply lines are typically made of steel
pipe or copper tubing.
Copper tubing has become the choice for
most applications because it’s easy to work
with, doesn’t require as many fittings and in
many instances, a continuous line can be run
from the burner to the tank. Each of these
factors reduces the amount of time necessary
to install a line and reduces the expense of the
installation. When copper tubing is used, the
line should be polyethylene-coated
and/or sleeved in protective tubing to substantially
reduce the risk of corrosion.
While studies have shown that fuel can
degrade when exposed to copper, NORA
recognizes the many advantages copper tubing
provides and this is the material of choice in
Whenever possible, each oil burner
should have its own oil line