Reassembly/Installation Of Injection Tube; Heater Reassembly - pick heaters 6X7 Service Manual

PICK VARIABLE FLOW SERVICE MANUAL
REASSEMBLY AND INSTALLATION
OF THE INJECTION TUBE (ALL
MODELS) SEE FIGURE 3
Be sure the inside of the injection tube is
clear of all deposits and foreign material.
Note that, in some heaters, the piston and
spring stopper have the same outside
diameter but are NOT interchangeable. The
piston has a .055" hole in the center of the
flat end, while the spring stopper has a ¼" or
larger hole. Reinstall the piston in the tube
so the pillow or open side of the piston is
facing the spring stopper end of the tube,
allowing the spring to fit inside the piston.
Reinstall the spring and spring stopper.
IMPORTANT: (Model 6X7 only) Install
the spring stopper with the open end over
the spring. The spring stopper will rest
under the shoulder bolt. SEE FIGURE 4
The spring stopper injection tube has scribe
marks (on the end of the tube) that indicate
the proper positioning for alignment of the
spring stopper bolt holes (except model
6X7). Reinstall the bolts that hold the
spring stopper in place, but DO NOT re-use
the old nuts.
IMPORTANT: Install NEW stainless
steel flexlock nuts to insure proper
locking. Replacements can be obtained
from Pick Heaters. SEE TABLE 2. (Page
12)
The model 6X7 injection tube uses a
shoulder bolt to hold the spring stopper in
place. Use a new stainless steel flexlock nut
when re-assembling. SEE TABLE 2
After the injection tube is reassembled,
make sure the piston operates freely. Check
to be sure there is no binding or restriction
in the tube by manually working the piston
through its full travel several times, using a
length of CLEAN rod.
HEATER REASSEMBLY (MODELS
6X10 THROUGH 6X500)
Inspect the inlet housing elbow and
associated piping for lime deposits and
debris. Remove any foreign material.
Examine the threads for damage.
Apply a moderate amount of paste-type pipe
sealant with Teflon to the injection tube
threads.
Note: Sealant must be FDA approved
when heating potable water.
IMPORTANT: Place the wrench over the
rivets, in the same position used when
loosening the tube. Tighten snug, but do
not over tighten. Applying force by using
an extra-long wrench, or by placing a
length of pipe over the handle of the
wrench, is likely to damage the injection
tube.
Examine the gasket surface for cleanliness,
and install a new gasket. Install the outlet
housing.
IMPORTANT: Carefully install the outlet
housing straight over the injection tube.
Avoid contact between the housing and
injection tube.
Reinstall all heater flange bolts and install
nuts finger-tight. Reassemble and tighten the
outlet union. If the union is flanged, clean
the gasket surface and install a new gasket.
Securely tighten all heater flange nuts,
working in a cross (alternate) patter. The
Pick heater may now be returned to
operation.
HEATER REASSEMBLY (MODEL
6X7) SEE FIGURE 4
If injection tube was removed from the
double-end bushing, apply a moderate
amount of paste-type pipe sealant with
Teflon to the injection tube threads.
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