750-211 (revised 2009)
Promethean Boilers, Model 4WI Manual
8-7
8.5 — Electrical Controls
Thermal relay units (overloads) are of the melting-alloy type and, when
tripped, the alloy must be given time to re-solidify before relay can be reset.
If the overloads trip out repeatedly when the motor current is normal,
replace them with new overloads. If the condition continues after replace-
ment, it will be necessary to determine the cause of excessive current draw
at the overloads.
Power supply to the boiler must be protected with dual element fuses
(Fusetrons®) or circuit breakers. Similar fuses should be used in branch
circuits. Standard one-shot fuses are not recommended. Information given
below is included for guidance to fuse requirements.
FIGURE 8-8.
Entry Box
Summary of Contents for 4WI
Page 46: ...Burner Operation and Control 2 22 750 211 revised 2009 Promethean Boilers Model 4WI Manual...
Page 62: ...Waterside Care and Requirements 3 16 750 211 revised 2009 Promethean Boilers Model 4WI Manual...
Page 70: ...Sequence of Operation 4 8 750 211 revised 2009 Promethean Boilers Model 4WI Manual...
Page 114: ...Adjustment Procedures 6 28 750 211 revised 2009 Promethean Boilers Model 4WI Manual...
