Beckett 800 Manuel D’Utilisation

9

125-200 psig

125-200 psig

3502

The burner is shipped without the by-pass plug in-
stalled.
Intall the by-pass plug in two-pipe oil supply systems 
ONLY.

y

y

Install the oil tank and oil lines in accordance with all 
applicable state and local codes.
Size the oil supply and return lines using the guidelines 
given in the fuel unit literature included in the literature 
envelope. Oil line fl ow rate will equal the burner rate for 
one-pipe systems. For two-pipe systems, refer to Table 
2  for the fuel unit gear set capacity - the rate at which 
fuel is recirculated when connected to a two-pipe system. 
However, size two-pipe oil lines based on this fl ow rate.
Use continuous lengths of heavy-wall copper tubing, 
routed under the fl oor where possible. Do not attach fuel 
lines to the appliance or to fl oor joists if possible. This will 
reduce vibration and noise transmission problems.
Install an oil fi lter sized to handle the fuel unit gearset fl ow 
capacity (Table 2) for two-pipe systems. Size the fi lter 

y

y

y

y

Carefully install the oil supply lines, fi ttings and com-
ponents using the guidelines provided in this section.
The oil supply must comply with the latest edition 
of NFPA 31 (Canada CSA B139) and all applicable 
codes.
Do NOT install valves in return lines.
If the oil supply inlet pressure to the pump exceeds 3 
psig or for gravity feed systems, install an oil safety or 
pressure reducing valve (Webster OSV, Suntec PRV or 
equivalent). 

y

y

y

y

Fuel unit by-pass plug

‰

The CF500 and CF800 burners are shipped without the 
by-pass plug installed in the fuel line.
The by-pass plug must NOT be installed when using with 
a one-pipe oil system.
The by-pass plug MUST be installed when using a two-
pipe oil system

.

Oil supply/return lines

y

y

y

‰

for the fi ring rate for one-pipe systems. Locate the fi lter 
immediately adjacent to the burner fuel unit.
Install two high-quality shut-off valves in accessible 
locations on the oil supply line. Locate one valve close 
to the tank. Locate the other valve close to the burner, 
upstream of the fuel fi lter.

Burner fuel fl ow

One-pipe systems – See Figure 8 for the fuel fl ow path.

Figure 7 is based on type B fuel unit.
Oil supply connects to one of the fuel unit inlet ports.

Two-pipe systems – See Figure 9 for the fuel fl ow paths 
for two-pipe oil systems.

Figure 9 is based on type B fuel unit .
Oil supply connects to one of the fuel unit inlet ports. 
Oil return connects to the fuel unit return port. (Install 
the by-pass plug in the fuel unit for two-pipe sys-
tems.)

y

‰

y

y

y

y

y

y

125-200 psig

125-200 psig

3503

Legend

a   Return port
b   Nozzle port
c   Oil valve
d   Nozzle & adapter
g   Inlet port
k   Return line to oil tank
p   Air bleed valve 

Fuel unit model number

Gearset capacity (GPH)

17

20

21

25

21

Nozzle pressure – The fuel unit nozzle port pressure 
is factory set at 140 psig. Some original equipment 
manufacturer burner applications may call for a lower 
pressure to obtain a required fi ring rate. Do not change 
this pressure unless directed to do so by the appliance 
manufacturer.

y