Starting The Boiler - Dunkirk PWXL Installation, Operation & Maintenance Manual

Blocked Vent Safety Shutoff
The blocked vent switch is a manual reset disc thermostat with a
fixed setpoint (340° F), and normally closed contacts. It is located at
the relief opening of the integral draft diverter. In the event of chim-
ney or venting system blockage causing products of combustion to
spill out of the relief opening, the blocked vent switch disc heats up
and the blocked vent switch contacts open, shutting down the flow
How A Hot-Water System Operates
Your entire heating system (boiler, piping and radiation units) is
filled with water. As the water in the boiler is heated, it is pumped
from the top of the boiler through the supply main to the radia-
tion units. The cooler water in them flows back through the return
main to the boiler. This provides positive and rapid response to the
thermostat.
!
Never run water into a hot empty boiler.
Filling System With Water
Close the air vents on all radiation units. Open the valves to these
units. Make sure the boiler and expansion tank drain cocks are
FOR YOUR SAFETY READ BEFORE OPERATING
IF YOU DO NOT FOLLOW THESE INSTRUCTIONS
EXACTLY, A FIRE OR EXPLOSION MAY RESULT
CAUSING PROPERTY DAMAGE, PERSONAL INJURY
OR LOSS OF LIFE.
1. Some boilers are equipped with an intermittent igni-
tion device which automatically lights the pilot. Do
!
not try to light the pilot by hand.
2. Some boilers are equipped with a continuous pilot
and must be manually lighted. (See lighting instruc-
tions.)
3. BEFORE OPERATING smell all around the appli-
ance area for gas. Be sure to smell next to the floor
because some gas is heavier than air and will settle on
the floor.
EquipmENT ANd OpTiONAL ACCESSOriES

STArTiNg ThE BOiLEr

WARNING
of gas to the main burners by removing power to the gas valve. In the
event that the blocked vent switch contacts open, the reset button on
the back of the switch will pop up. The blocked vent switch must be
reset manually, after the switch has cooled off, by pushing the reset
button down. Check the venting system and chimney for blockage
when restoring the system to operating condition. DO NOT operate
the boiler without a blocked vent switch.
closed. The air bleed screw on the expansion tank drain fitting
should be closed. Open the valve in the line from the boiler to the
expansion tank. Open the water inlet to your boiler and leave it
open. Start with the lowest radiation unit. Open the air vent on this
unit. When all the air has escaped and water starts to flow from the
vent, close it. Go to the next radiation unit, and repeat this process.
Repeat until you have covered every radiation unit in the system
(ending up at the highest unit in the system). If your units have auto-
matic vents, this manual venting is unnecessary but it will speed up
the proper filling of your system. If your system is a closed expansion
tank system, you may leave it open to refill the system automatically
as needed. Check the temperature pressure gauge, NOT the position
of the hand indicating the pressure. This should be between 10 and
15 lbs. any lowering of this movable hand below 10 lbs. will indicate
loss of water due to leakage. The automatic fill valve should compen-
sate for this. Instructions are packaged with the valve.
WARNING
WHAT TO DO IF YOU SMELL GAS
• Do not try to light any appliance.
• Do not touch any electric switch; do not use any phone in
your building.
• Immediately call your gas supplier from a neighbor's
phone. Follow the gas supplier's instructions.
• If you cannot reach your gas supplier, call the fire depart-
ment.
4. Use only your hand to push in or turn the gas control knob.
Never use tools. If the knob will not push in or turn by hand,
don't try to repair it, call a qualified service technician. Force
or attempted repair may result in a fire or explosion.
5. Do not use this appliance if any part has been under water.
Immediately call a qualified service technician to inspect the
appliance and to replace any part of the control system and
any gas control which has been under water.
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