Finned copper tube gas boilers & water heaters – Boiler Manual
35
Figure 21
Heat Exchanger Upper Rail Screws
Vent System
Thoroughly inspect the vent system for any signs of blockage,
corrosion or leakage. Immediately replace any unsound vent system
piping.
Controls
Use the "BOILER/WATER HEATER OPERATION" and
"CHECKING AND ADJUSTMENTS" sections of this manual
for reference.
1. Check the thermostat or operating controls for proper operation.
2. float type low water cutoff device must be flushed out per the
manufacturers' instructions. The probe on a probe low water
cut off must be removed, cleaned and inspected at least once
a year. Ensure that the low water cutoffs operate properly. If not,
replace them.
3. The flow switch contacts must be open when water flow is not
present.
4. The relief valve should not weep or discharge water at normal
system pressure. If it does, contact a qualified service technician
to have it inspected. NEVER try to clean or repair the relief
valve! If the valve fails to operate properly, have it replaced!
5. The aquastat high limit controls the maximum water
temperature in the boiler. It should be set at least
20°F
,
11°C
above the operator setpoint. If the water temperature reaches the
set temperature before the demand for heat has been met, the
aquastat high limit should shut the boiler off. The water
temperature should never exceed the maximum set point of
240°F
,
116 °C
. The aquastat high limit cannot be repaired. If
it fails to function properly replace it.
6. Visually check the pilot and main burner flames to ensure proper
operation, see Figure 22.
A yellow, floating flame indicates a lack of combus-
tion air. A lifting flame indicates too much combustion
air. Do not operate the boiler/water heater until the
problem is solved or severe personal injury or death
may occur!
Figure 22
Pilot and Main Burner Flame
