Modine Manufacturing POR Installation And Service Manual page 7

installation
Piping
CAUTION
Remove bypass plug from fuel unit when unit is connected to
one pipe oil system. Failure to do so will permanently damage
fuel unit and void warranty.
1. Recommend all piping be done in accordance with NFPA
No. 31 "Installation of Oil Burning Equipment" and all local
codes.
2. All piping shall be steel or brass pipe, with UL - listed fittings.
Galvanized or wrought iron pipe is not recommended. 1/2
inch O.D. copper tubing with flared fittings is recommended
for connecting the tank to the burner.
3. Protect piping from possible injury and fasten in place.
Where practicable, it should be buried underground, or
in a concrete floor, or placed in a metal-covered pipe
trench. Do not cover piping until burner has been installed
and operated so that any leaks may be corrected. Use
non-hardening pipe thread compound resistant to oil for
threaded connections.
IMPORTANT: ALL PIPE AND/OR TUBE FITTINGS ON FEED
LINE TO BURNER MUST BE ABSOLUTELY AIR TIGHT! USE
ONLY FLARED FITTINGS ON TUBING CONNECTIONS. DO
NOT USE COMPRESSION FITTINGS.
single-unit Piping
two Pipe system
Modine oil-fired unit heaters are equipped with two-stage fuel
units. They are recommended for use on two-pipe systems.
(Supply and return lines connected to fuel unit) in high lift
applications, up to 15 inches Hg (Mercury) inlet vacuum (20 foot
vertical lift or equivalent) when directly connected to a supply
tank. All unit heaters are shipped for use on two pipe systems.
See Figure 8.1. If more than one unit is piped to the same tank,
separate suction oil lines must be installed for each unit. A
single common line, however, can be piped in series for fuel oil
return.
one Pipe system
The fuel units supplied contain an internal by-pass and are
shipped from the factory with the by-pass plug in place. for one
pipe installations (only supply line connected to fuel unit)
remove this plug or permanent damage to fuel unit will
occur. One pipe systems are not recommended when vertical
lift exceeds 10 feet.
Piping selection
Table 7.1 can be used to approximate system piping
requirements for two pipe systems. Determine the total lift in feet
from the bottom of the supply tank to the fuel unit and subtract
from 20 feet. This is the reserve available in feet of oil for piping
losses. Determine the total equivalent length of piping by adding
the total straight lengths to the equivalent length of straight
pipe for each elbow and tee per Table 8.1. Locate the point
of intersection of the total equivalent length of piping and the
reserve piping loss in feet of oil on the graph. Always use the
pipe size below this point on the graph to allow for unforeseen
losses and ample reserve for filter losses.
table 7.1
Burner fuel unit capacity
figure 7.2
fuel unit, Beckett
4-522.4
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