BOILER START-UP AND ADJUSTMENTS
FILL SYSTEM
1. Close manual air vents (if used) and automatic air vents. Attach hose to boiler drain
on return connection and run to a drain or to outdoors. Open drain cock and close
shutoff valve on boiler supply pipe.
2. HEATING ONLY – SINGLE ZONE SYSTEM---
Open manual valve in cold water feed line and set the fill valve to fast fill. Allow
water to flow through the system and out the hose until there is a steady flow of water
through the hose with no air bubbles.
Next, open the shutoff valve in the drain until air bubbles cease. Then take the fill
valve off fast fill, close the drain cock, remove the hose and open all automatic air
vents.
Also open all manual air vents one at a time and close when water squirts out.
Observe the temperature/pressure gauge. System pressure with a cold fill should be
in the 12 to 14 psi range.
3. MULTI-ZONE SYSTEMS-HEATING ONLY OR HEAT & DOMESTIC HOT
WATER WITH ZONE VALVES---
To ensure good circulation through all zones with no air pockets, each zone should be
purged of air individually. With all zone valves in the manual open position let water
flow through the system by opening the drain cocks so water can exit the system
through a hose as in 1. above.
When system seems to be full and free of air, close the drain cock, and the shutoff
valve on the boiler supply pipe, leaving the manual valve on the cold water feed open.
Now release the manual openers to close all but one zone valve. Open the drain cock
and put the fill valve on fast fill. When the flow through hose becomes steady with
no air bubbles, take the fill valve off fast fill and then close the drain cock.
Repeat this procedure with each zone until all zones have been purged. Open the
shutoff valve on the boiler supply pipe. Then open all manual air vents one at a time.
When water sprays out of the air vents should have the cap loosened so it can vent air.
4. MULTI-ZONE SYSTEMS ZONED WITH CIRCULATORS---
Following the same procedures as in 3. above using the manual shutoff valves to
isolate a zone instead of zone valves.
5. Check system pressure on the temperature/pressure gauge on the boiler. Pressure
should be in the 12 to 14 psi range. If pressure is over 14 psi drain a little water out
with the drain cock. Watch gauge for a few minutes to ensure pressure does not build
back up. If pressure is too high with system cold there is a good possibility the relief
valve will blow off when the system is brought up to temperature. Too high a
pressure with the system cold indicates a faulty fill valve.
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Installation, Operation, And Service Instructions
