FULTON PDWH1000, Installation, Operation And Maintanance Manual

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Installation
Figure 5b
Sequence of Operation
1. Turn on main breaker.
2. Low water safety relay (LWSR) is
energized when the main breaker is
turned on. (Red light on the water
heater panel is lit and if the optional
alarm is provided, alarm will go off.
Current is not allowed to pass to the
high limit temperature control until a)
the probe in the water heater shell
senses the water and b) the manual
reset switch is reset. If a and b are
both satisfied, the red light is turned
off.
3. High limit temperature control allows
current to pass to the next control if
the temperature in the water heater
water is not causing the control to
open the circuit.
4. Burner switch is then closed to ener-
gize the operating temperature con-
trol. (Green light on the panel is lit).
5. Operating temperature control
allows current to pass to the auto-
matic control relay if the temperature
of the water is not causing the
control to open the circuit.
6. 120V power is input to the automatic
control relay (RM7865A).
7. Purge blower is energized for 35
seconds.
8. Purge fan switch is made, signaling
the control to proceed.
9. Spark plug is energized.
10. Gas valve is energized.
11. Pressure sensing switch is made
(proof of flame) allowing sequence
to continue.
12. Pulse combustion will continue
until one or more of the following
things happen:
A. Operating temperature control is
satisfied.
B. High limit temperature control is
satisfied.
C. Low water safety relay loses
water on probe.
D. Burner switch is turned off.
E. Main breaker is turned off.
Glossary
AC — Audible Alarm Control
(Optional)
ACR — Automatic Control Relay
(7800 series)
BM — Purge Fan Motor
BS — Burner Switch
CR — Control Relay
HLTC — Hi Limit Temp. Control
LW
— Panel Light (Low Water
Indicator)
LWCP — Low Water Cutoff Probe
LWRS — Low Water Reset Switch
LWSR — Low Water Safety Relay
GV
— Main Gas Valve
OTC — Operating Temp. Control
PFS — Purge Fan Switch
PL — Panel Light (Power On Green)
PSS — Pressure Sensor Switch No. 2
RC — Relay Coil
SP — Spark Generator
S.P. — Spark Plug
TB-H — Terminal Block (Hot)
TB-N — Terminal Block (Neutral)
15-PDWH