Cover screw with silicone sealant to prevent movement of screw by vibration.
Hold Fire Thermostat Adjustment (Refer to Figure 4-69).
Hold fire thermostat adjustment maintains the minimum heat level required to keep the
heater circuitry operational.
(1) With power off, remove elbow (5) by removing screws (4). Remove profile trim (5A) from elbow (5).
Position stop to provide the lowest practical control range.
With power on, start the heater. Move stop to the left to increase the temperature in the control range, or proceed as
Move stop (7) to the right to decrease the temperature in the control range.
Tighten setscrew (6) after adjusting stop (7).
Electrical power must be off at the source prior to any disassembly. Failure to do so could
result in severe injury or death.
If heater has been operated recently, allow it to cool before proceeding. Exhaust heat could
cause severe burns and/or present a fire hazard.
Disconnect heater power cable (8) at the base of the heater assembly (9).
Disconnect fuel line (10) at base of heater assembly (9).
Remove four capscrews (11), washers (12), nuts (13), lockwashers (14) and washers (15). Remove exhaust shroud (16).
Do not remove the exhaust pipe from the ROWPU wall unless required.
Remove four nuts (17) and washers (18) from studs (19). Pull down on flange (20) to separate the exhaust flange (20) from
the heater assembly (9). If necessary, remove gasket (21).
Remove four capscrews (22), washers (23), nuts (24), lockwashers (25), and washers (26) (two from bracket (27) and two
from bracket (28).).
Remove heater assembly (9) as an assembly.
Remove four capscrews (29), remove the control box cover (30).
Disconnect and tag wires.
Remove four capscrews (31), lockwashers (32), nuts (33), lockwashers (34) and washers (35) and remove control box (36).
Remove four capscrews (37), lockwashers (38), washers (39), and remove bracket (27).
Remove two capscrews (40), lockwashers (41), washers (42) and remove bracket (28).
If necessary, on Model ROWPU-1, remove elbow (43C) and nipple (43D) from ROWPU wall.
l. If necessary, remove elbow (43A) and pipe (43B) from ROWPU wall.
If necessary, drill out rivets (44) and remove flange (45). (46) DELETED.
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