Weil-McLain 78 Boiler For Gas, Light Oil, Gas/Light Oil Fired Burners
Make Final Adjustments
14b
Skim steam boilers:
Clean all newly install steam boilers to remove
oil. Failure to properly clean can result in
violent water level fluctuations, water passing
into steam mains, or high maintenance costs on
strainers, traps and vents. Skim boiler only. Do
not clean old piping or leaks can occur.
Do not use petroleum-based cleaning or sealing
compounds in boiler system. Severe damage to
system components can result, causing
substantial property damage.
1. Remove 2" plug from 3" x 2" bushing at skim
tapping. Provide 2" skim piping from tapping
to floor drain.
2. Raise waterline to midpoint of skim piping.
3. Fire burner to maintain temperature below
steaming rate during skimming process.
4. Feed in water to maintain water level. Cycle
burner to prevent rise in steam pressure.
5. Continue skimming until discharge is clear.
This may take several hours.
6. Drain boiler. While boiler is warm but not
hot, flush all interior surfaces under full
pressure until drain water runs clear.
7. Remove skim piping. Re-insert plug at boiler
skim tapping.
8. Close drain cock. Fill with fresh water to
normal water line. Start burner and steam for
15 minutes to remove dissolved gases. Stop
burner.
9. Check traps and air vents for proper
operation.
Determine if water treatment is
needed (water boilers only):
Do not use petroleum-based
cleaning or sealing compounds
in boiler system. Severe damage
to system components can
result, causing substantial
property damage.
Continual make-up water will reduce boiler life.
Minerals can build up in sections, reducing heat
transfer, overheating cast iron and causing
section failure.
For unusually hard water areas or low pH
conditions (less than 7.0) consult local water
treatment company.
Freeze protection (when used):
1. Use antifreeze especially made for hydronic
systems. Inhibited propylene glycol is
recommended.
Do not use automotive, ethylene
glycol or undiluted antifreeze.
Severe personal injury or death
can result.
2. 50% solution provides protection to about
-30°F.
3. Local codes may require back-flow preventer
or actual disconnect from city water supply.
4. Determine quantity according to system water
content. Boiler water content is listed on page
31. Percent of solution will affect sizing of
heat distribution units, circulator and
expansion tank.
5. Follow antifreeze manufacturer’s instructions.
Check boiler for gas-tight seal:
Boiler must be sealed gas-tight
to prevent possible flue gas
leakage and carbon monoxide
emissions, resulting in severe
personal injury or death.
1. Remove boiler jacket side and top panels.
2. Start burner. Observe all sealing points and
chalk mark any not gas-tight.
3. To seal all chalk-marked areas:
a. use silicone sealant on section flueways.
b. check gaskets and sealing rope placement.
4. Reinstall all jacket panels.
Part No. 550-141-705
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