37
Section 7 - Filling System with Water and Purging Air
SECTION 7 – FILLING SYSTEM WITH WATER
AND PURGING AIR
Before firing the outdoor furnace for the first time,
perform the following important steps:
1. Check for leaks. Close the valves on the outdoor
furnace before checking for leaks. Do not pressurize
the outdoor furnace. Pressure-test the entire
plumbing system. Apply 50 psi (3.5 kg/cm
2
) of
air pressure for thirty minutes and closely monitor
for any pressure loss. Inspect all fittings and hose
ends for any signs of leakage using leak detection
solution (leak soap); repair as necessary.
2. Cover Supply and Return Lines. Backfill the
trench for the supply and return lines. Enclose the
area where the supply and return lines enter the
outdoor furnace. Do not leave the PEX hot supply
and return lines exposed to sunlight as exposure to
UV rays will damage them.
3. Add Corrosion Inhibitor Plus™. Add Corrosion
Inhibitor Plus™ (p/n 1650) through the vent pipe
on the outdoor furnace before filling with water
to immediately begin to protect the steel. Refer to
Water Quality and Maintenance.
4. Turn the FireStar controller on by pressing the
Power
button. The LED display should flash
to indicate that the water level is below the
sensor.
5. Fill with water, purge air from system and verify
flow direction of the water. See Filling Outdoor
Furnace with Water and Purging Air for details.
6. Install the vent cap. The vent cap must fit loosely
over the outdoor furnace vent.
FILLING OUTDOOR FURNACE WITH WATER
AND PURGING AIR
NOTE: The items referred to in this procedure
correspond to the items in Fig. 47. Refer to Fig.
47 when performing these steps.
All air must be purged from the water lines when filling
the system. Also, the circulation pump(s) must be
installed in the hot supply line(s).
NOTE: If using the valve on the water heater to
fill the outdoor furnace, flush the water heater
to remove all sediment before filling the outdoor
furnace.
NOTE: If the outdoor furnace is being filled with
water when the temperature is below freezing,
circulate the water immediately after filling to
prevent freezing the water lines.
NOTE: Be sure to fill the outdoor furnace with
water of good quality (softened water, if possible).
See Water Quality and Maintenance section.
Use the procedure in this section to fill the outdoor
furnace with water and purge the air from the system.
All valves in the outdoor furnace system that allow
circulation through each circuit should be open before
starting. Perform this procedure on each pump circuit
from the outdoor furnace.
NOTE: Add Corrosion Inhibitor Plus™ (p/n 1650)
through the 2-inch vent pipe on the outdoor
furnace before filling with water to immediately
begin to protect the steel.
H
C
M
R
Hot
Supply
Backflow
Preventer
Hot
Supply
Valve #1
1" Central
PEX
®
Bypass
Line
Plenum
Forced Air
Furnace
Return Line
NOTE: For illustration purposes only.
Actual configuration may vary.
NOTE
Installer must comply with
all applicable codes and
regulations.
NOTE
A pump must be installed in the hot
supply line between the outdoor furnace
and thermostatic valve.
Valve #2
Valve #5
Thermostatic
Valve
Valve #3
Hose A
Valve #4
Valve #6
(Seasonal Manual
Bypass Valve)
Water
Heater
© 2015 Central Boiler
NOTE
Outdoor furnace water temp
setpoint should be set at
185˚F (85˚C) minimum.
Filling Outdoor Furnace and Purging Air
Using Pressurized Domestic Water
Fig. 47
