Boiler Manual
Part Number 550-110-593/1099 29
Fill the system with waterInspect system water piping
After filling the boiler and system with water, inspect all piping throughout the system for
leaks. If found, repair immediately. Repeat this inspection after the boiler has been started and
the system has heated up.
Do not use petroleum-based cleaning or sealing compounds in boiler system. Severe damage
to boiler will occur, resulting in substantial property damage.
Leaks must be repaired at once. Failure to do so can damage the boiler, resulting in substantial
property damage.
1. Close manual and automatic air vents and boiler drain cock.
2. Fill to correct system pressure. Correct pressure will vary with each application. Typical
cold water fill pressure for a residential system is 12 psi.
3. Purge air from system:
a. Connect a hose to the purge valve (see drain valves, item 6, in suggested piping diagrams
on pages 17 through 23, Figure 9 through Figure 16). Route hose to an area where
water can drain and be seen.
b. Close the boiler or system isolation valve between the purge valve and fill connection
to the system.
c. Close zone isolation valves.
d. Open quick-fill valve on cold water makeup line.
e. Open purge valve.
f. One zone at a time, open the isolation valves. Allow water to run through the zone,
pushing out the air. Run until no noticeable air flow is present. Close the zone isolation
valves and proceed with the next zone. Follow this procedure until all zones are purged.
g. Close the quick-fill water valve and purge valve and remove the hose. Open all isolation
valves. Watch that system pressure rises to correct cold-fill pressure.
h. After the system has operated for a while, eliminate any residual air by using the manual
air vents located throughout the system.
i. If purge valves are not installed in system, open manual air vents in system one at a
time, beginning with lowest floor. Close vent when water squirts out. Repeat with
remaining vents.
4. Open automatic air vent (diaphragm-type or bladder-type expansion tank systems only)
one turn.
5. Open other vents:
a. Starting on the lowest floor, open air vents one at a time until water squirts out.
b. Repeat with remaining vents.
6. Refill to correct pressure.