Graco 226816, Instructions-Parts List Manual

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307363 11
Maintenance
Flushing After Use
1. Drain and clean the fluid filter frequently to be sure
it filters the fluid thoroughly. Always relieve system
pressure first, and cool the fluid, if possible. If not
possible, wear protective eyewear and gloves to
protect yourself from possible burns.
2. Flush the heater often enough to prevent a buildup
of dried sediment in it.
WARNING
Before flushing, always shut off the main power to
the heater. Circulate the fluid through the system
for at least 10 minutes to cool the fluid and heater.
This reduces the risk of serious injury from burns.
CAUTION
Clogged fluid passages can be very difficult to clean.
They also reduce heating efficiency, flow rate, and
pressure. To prevent clogged passages, do not
overheat or dry out the fluid, and flush frequently,
including whenever the system or heater is not in
use.
3. If the system runs dry, refill it immediately before
fluid can dry in it. Or flush the system thoroughly if
you are not going to use it immediately.
4. To drain the fluid from the heater, first relieve all
system pressure. Cool the fluid, if possible. Re-
move the drain plug (7) in either end plate and
drain the fluid into a container. See. Fig. 8.
5. Shut down.
CAUTION
When shutting down the system, turn the control
knob (V) to set point 1 and circulate the fluid for at
least 10 minutes before shutting off the pump. This
allows unheated fluid to gradually cool the heater and
heated fluid.
Fig. 8
V
9
7
Unclogging Fluid Passages
1. Remove an end plate (21) and use a wire bottle
brush to clean. If necessary, use 1/2 in. (13 mm)
hand reamer to remove hard, caked deposits.
2. Put the end plate back on, turning all screws hand
tight.
3. Follow the sequence shown in Fig. 9, torquing
each screw to 50 in-lb (5.6 N
S
m).
4. Torque them again, using the same sequence, to
175–225 in-lb (20–25 N
S
m).
Fig. 9
Torquing Sequence