Raypak RAYTHERM 133, Инструкция по установке и эксплуатации

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48
Tube Replacement
1. Remove heat exchanger from heater following
instructions outlined under HEAT EXCHANGER
REMOVAL on page 45.
2. Remove in/out and return headers. Remove "V"
baffle from damaged tube.
3. Remove damaged tube by cutting with a hack saw
or shearing with a chisel adjacent to each tube
sheet.
4. Collapse stub ends in tube sheets using a chisel or
screwdriver. DO NOT cut into tube sheet or mar
surface in tube hole in any way.
5. Insert replacement tube by inserting the end with
the most fins removed in the opening of one tube
sheet. Slide tube until the opposite end clears the
other tube sheet and fit the tube into the hole.
6. Insert the tube roller into tube opening up to stop,
making certain that 1/8" of tube projects beyond
the tube sheet.
7. Attach drill to tube roller, holding it straight and
level. Note: Use a 3/8" heavy duty, reversible,
electric drill or larger. Proceed to expand tube until
tool starts to grab. Approximately 1/2 to 1" of the
tool shank will be visible.
8. Reverse drill motor and withdraw tube roller, If
necessary wrench out by hand.
9. DO NOT apply excessive torque during rolling
operation and avoid thinning any wall of the tube
beyond 0.015".
10. Use same procedure on opposite end.
11. Apply line pressure test. Re-roll if necessary.
12. Reinstall as outlined under HEAT EXCHANGER
REASSEMBLY.
Combustion Chamber Removal
To remove combustion chamber refractory you must
first have removed the heat exchanger. Unbolt metal
combustion chamber retainer from top and remove
refractory panels individually.
Control Well Replacement
Remove top, sensing bulb and clip. Collapse well tube
at the open and with a chisel, push through into head-
er and remove the well through header. Insert a new
well and roll into place. If a roller is not available, sol-
der the well in place with silver solder.
Fig. 41: Refractory Panels—Top View
WARNING:
This unit contains refractory ceramic
fiber (RCF) insulation in the combustion chamber.
RCF, as manufactured, does not contain respirable
crystalline silica. However, following sustained
exposure to very high temperatures (>2192
°
F), the
RCF can transform into crystalline silica
(cristabolite). The International Agency for Research
on Cancer (IARC) has classified the inhalation of
crystalline silica (cristabolite) as carcinogenic to
humans.
When removing the burners or heat exchangers,
take precautions to avoid creating airborne dust and
avoid inhaling airborne fibers. When cleaning spills,
use wet sweeping or High Efficiency Particulate Air
(HEPA) filtered vacuum to minimize airborne dust.
Use feasible engineering controls such as local
exhaust ventilation or dust collecting systems to
minimize airborne dust. Wear appropriate personal
protective equipment including gloves, safety
glasses with side shields, and appropriate NIOSH
certified respiratory protection, to avoid inhalation of
airborne dust and airborne fiber particles.