20
Part Number 550-110-772/0816
OSB
Series 2
Oil-Fired Steam Boilers –
Boiler Manual
10 Service and maintenance
continued
Gauge glass
Normal waterline is halfway up gauge glass. Clean when needed.
1. Close lower gauge cock.
2. Open pet cock.
3. Open lower gauge cock and allow a small amount of water to
flush out through open pet cock.
4. Close pet cock.
5. Open lower gauge cock.
Boiler pressure must be low to eliminate potential
of severe burns.
If gauge glass breaks, close both gauge cocks.
Replace gauge glass. Do not replace with thin glass
tubing. Failure to comply could cause severe per-
sonal injury, death or substantial property damage.
❏
Service. . . . . . . . . .
❏
Check/test. . . . . . . . . .
Boiler waterline
Normal waterline is halfway up gauge glass.
Limit controls
1. Inspect and test the boiler limit control. Verify operation by
turning control set point below boiler pressure. Boiler should
cycle off. Return dial to original setting.
❏
Check/test. . . . . . . . . .
Low water cutoffs
Probe-type low water cutoff (see below)
Clean and test probe-type low water cutoff for proper operation.
Remove, inspect and clean the low water cutoff at least annually
before testing. Refer to low water cutoff manufacturer’s instructions
in envelope assembly provided with boiler.
1. Turn off power to boiler and wait 5 minutes.
2. Drain water to bottom of gauge glass.
3. Turn on power.
4. Set thermostat to call for heat. Red neon lamp on lower water
cutoff should light.
5. Wait 5 minutes. Boiler should not fire.
6. Refill boiler to correct waterline. Red lamp should go off.
7. Wait 5 minutes. Boiler should fire.
8. Return thermostat to normal setting.
Float-type low water cutoff (when provided by others
— see below)
Clean and test float-type low water cutoff (when provided by
others) to clear float chamber of sediment.
1. Open blowdown valve at bottom control.
2. Drain water into a bucket.
Scald potential. Boiler pressure must be low to avoid
the potential of severe burns from steam.
3. Check float-type low water cutoff for proper operation:
a. Turn operating control to call for heat.
b. Before water gets hot, drain to bottom of gauge glass.
Boiler should shut off after water level lowers a few inches.
c. Refill boiler to correct waterline. Boiler should come back on.
