(2)  
SWPM 20-30-12

 (3)  
WDM 30-71-11, WDM 30-71-12, WDM 30-71-13, WDM 30-71-14

 B.  Access
 (1)  Location Zone 125 thru 152 Lower Lobe (Refer to WDM for heater locations)
 C.  Procedure
 S 864-002
 (1) Open these circuit breakers and attach DO-NOT-CLOSE tags:
 (a)  P414, Left Power Distribution Center 1) 414A24, WASTE AND WATER LINE HTR MN PWR 2) 414D5, WASTE AND WATER LINE HTR MN PWR 3) 414L22, DRAIN MAST HTR AIR FWD 4) 414L23, DRAIN MAST HTR AIR CTR 5) 414L24, DRAIN MAST HTR AIR AFT 6) 414C21, DRAIN MAST HTRS GND SVCE MODE
 S 014-003
 (2)  
Remove floor or sidewall panels to get access to the applicable ribbon heater.

 S 034-004

 (3)  
Cut the ribbon heater electrical leads (SWPM 20-30-12).

 NOTE:____Let the cut electrical leads stay where they are. This will help you to find the splice. Remove them when you make a splice with the new leads.
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LEAD WIRES
Ribbon Heater Installation
Figure 401

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 S 034-005
 (4)
Remove the tape which holds the heater to the water or drain line.

 S 024-012

 (5)
Remove the ribbon heater from the water or drain line.

 TASK 30-71-01-404-006
 3.  Ribbon Heater Installation (Fig. 401)__________________________
 A. Consumable Materials
 (1)
G00646, Strap - Tie Down

 (2)
G00134, Tape - Adhesive, Flame-Resistant, 1.5-inch wide

 B. References
 (1)
AMM 30-71-00/501, Water Line and Waste Drain Heaters

 (2)
AIPC 30-71-01, Fig. 2

 (3)
SSM 30-71-01

 (4)
SWPM 20-30-12

 (5)
WDM 30-71-11, WDM 30-71-12, WDM 30-71-13, WDM 30-71-14

 C. Access
 (1)  Location Zone 125 thru 152 Lower Lobe (Refer to WDM for heater locations)
 D. Procedure
 S 424-007
 CAUTION: INCORRECT INSTALLATION OF RIBBON HEATERS AND INSULATION CAN
_______
 CAUSE HEATER FAILURE OR DAMAGE.

 DO NOT LET RIBBON HEATERS HAVE AN OVERLAP.
 DO NOT INSTALL CLAMPS OR STRAPS FROM PLUMBING INSTALLATIONS OVER RIBBON HEATERS.
 SUPPLY 1.0 INCH MINIMUM CLEARANCE BETWEEN THE RIBBON HEATERS AND THE INSULATION. DO NOT INSTALL INSULATION BLANKETS OVER RIBBON HEATERS.
 ATTACH RIBBON HEATER TERMINAL BUTTONS WITH TWO LOOPS OF FLAME-RESISTANT ADHESIVE TAPE.
 ATTACH ELECTRICAL LEAD WIRES WITH A STRAP.
 IF THE HEATER IS TOO LONG, INCREASE THE NUMBER OF WRAPS, BUT DO NOT LET THE HEATERS HAVE AN OVERLAP.
 (1) Install the ribbon heater:
 (a) Put the ribbon heater in position on the water or drain line.
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MAINTENANCE MANUAL

 (b) (c) (d) (e) (f)  Attach one end of the heater with two loops of tape (Fig. 401).Make wraps of the heater around the water or drain line with 3.0 inches between subsequent wraps.Put tape continuously along the length of the heater. Attach the end with 2 wraps of flame resistant adhesive tape.Find the splice area and make a splice of the electrical leads (SWPM 20-30-12).Attach the lead wires with a strap.
　
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