General Maintenance; Oiled Bearing Circulators - Weil-McLain 550 MBH Nstallation And Operation Manual

®
SlimFit Series 3
Maintenance
Disconnect power
Electrical shock hazard — Disconnect all electrical
power to the boiler before attempting maintenance
procedures. Failure to complete could result in se-
vere personal injury, death or substantial property
damage.
Install boiler jacket front door after
startup or servicing
Reinstall boiler jacket front door after start-up or
servicing. The boiler front door must be securely
fastened to the boiler to prevent boiler from drawing
air from inside the boiler room. This is particularly
important if the boiler is located in the same room
as other appliances.
Inspect boiler jacket door gaskets. Gaskets must be
in good condition, with no tears or gaps. Replace if
necessary.
Failure to keep the door securely sealed and fastened
could result in severe personal injury or death.
Perform start-up and check/out
Removing and reinstalling components can change
boiler behavior. After any maintenance procedure,
you must prove the boiler is operating correctly. To
do so, follow the complete procedure for boiler and
system start-up, beginning on page 85. Failure to
comply could result in severe personal injury, death
or substantial property damage.

General maintenance

1. Oil motors in system requiring regular oiling.
2. See Oiled bearing circulators for motor oiling procedures.

Oiled bearing circulators

1. Check circulators in the system. Oil any circulators requiring oil,
following circulator manufacturer's instructions. Over-oiling will
damage the circulator.
Part number 550-100-168/0516
COMMERCIAL CONDENSING GAS
—
-
FIRED WATER BOILER
Cleaning the heat exchanger — pin
side when required
1. Shut down boiler:
a. Follow "To Turn Off Gas to Appliance" instructions
on boiler and Lighting instructions.
b. Do not drain boiler unless it will be exposed to freez-
ing temperatures. If using freeze prevention fluid in
system, do not drain.
2. Allow time for boiler to cool to room temperature if it
has been firing.
3. Rotate the two rotary latches on the front door. Tilt
the top of the door forward, then lift up. Use a 13-mm
wrench or socket to remove the nuts on the front cover
plate and remove the plate. Use the cleanout plug in the
flue pipe to rinse debris into the condensate drain. Flush
the condensate drain, then refill.
4. Follow the applicable procedures under "Accessing &
cleaning the heat exchanger," page 106.
Clean the cast aluminum heat exchanger
when required — water side
1. In order for the efficiency of boilers to increase beyond
the condensing limit, new materials have been intro-
duced for the heat exchanger, including aluminum.
2. Aluminum has excellent heat transfer characteristics
and is light in weight.
3. These new materials also require cleaning solutions
that differ from those used in conventional cast iron
and steel boilers.
One common cleaning method that
be used with systems containing aluminum is
a solution of trisodium phosphate, commonly
referred to as "TSP."
The reason that trisodium phosphate cannot
be used is that the cleaning solution has a very
high pH level — while removing the scale in
the system, it also removes the natural pro-
tective oxide layer from the aluminum. The
oxide layer will reform, but if small amounts
of the trisodium phosphate remain in the
system, the chemical will continue to remove
the protective oxide layer, leading to reduced
heat exchanger life.
4. Use ONLY the cleaning product available from Weil-
McLain, Sentinel X400. See the Repair Parts section at
the end of this manual for ordering information.
Boiler Manual
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