CLEANING AND FILLING A NEW STEAM BOilER
MODELS WITH TANK LESS HEATER OR WITH
TANKLESS HEATER PLATES ONLY.
A. Turn off electrical power supply to boiler. Allow
boiler to cool down and allow pressure to reduce to
zero before attempting removal of components.
Check for steam pressure by testing si:lfety valve
Keep your hands and body away from the discharge
end of the valve. Remove pop safety valve and reo
pipe boiler as shown in Figure (B) below, making
sure to reinstall pop safety valve on tee to complete
the blow off connection
B Connect a length of pipe to the elbow and place a
bucket underneath the open end of the pipe, cover
bucket with a piece of cloth
C. Open the SKIMMER drain valve with caution. DO
NOT open the boiler drain valve Fill the boiler slow·
Iy until water begins to seep into the bucket from
the skimmer drain blow off connection Fire the
boiler. Allow water to heat up while water seeps In·
to the bucket. Maintain that water level necessary
just to be able to continue skimming. Continue until
water is clean and no oil can be seen floating in the
bucket. Empty bucket frequently in order to see if
the water is clean.
D. Repeat this process until all film IS skimmed off, lower
the water level to 29-1/2 inches from the bottom of the
boiler (see Figure (B) below). When all surging has
stopped, turn off the boiler, remove skimmer valve and
plug the tee. Check the pop safety valve for proper
operation.
E. The entire process may have to be repeated over a
period of a few days on extremely fouled systems.
CLEANING PIPING SYSTEM
A. To clean piping system, open all valves at the
heating elements, after getting up a good head of
steam, shut the boiler down and allow the conden-
sate to return to the boiler. The condensate will
carry the oil film with it. Again blow-off the boiler.
On extremely fouled systems, it may require several
visits over a period of a few days to clean the
system.
B. When steam only (no water) is released through the
hand valve, the boiler will not surge or flood.
FLOAT TYPE LOW WATER CUT-OFF
If thiS boiler ISfactory equipped wltha McDonnell &Miller
float type low water cut-otf, the low water cut-off must be
blown down (flushed), at least once a week.
CAUTION When flushing float type low water cut-off
cOl1trol, hot water and steam will flow out the blow down
valve. Blow down valve ISillustrated on page 4.
Steam controls assembly.
1. SPECIAL FLUSHING
INSTRUCTIONS
For new bOiler Installed
In old system
Installation of new boiler may break loose a
heavy accumulation of sediment and scale
from old piping and radiators It ISextreme·
Iy important to blow down your McDonnell
, Cut-off more frequently the first week
iFirst week-3 tilDes
lThereafter-at leasl once a week
2. As boiler water Circulates through the float
chamber, dirt or other sediment may be
deposited. ThiS chamber is extra deep But
the only sure way to keep any accumulation
from interfering with float action is to "blow
down," or flush out, the control once a week
00 it while boiler is tn operation. First note
water level in gauge glass. Open blow-off
valve at bottom of control; water will pour
out, flushing away sediment Drain until
water is clear-about a pail-then close
valve. If level In gauge glass has dropped add
water to boiler to restore level
3. NOTE: Opening blow-off valve checks cut-off
operation too. As float drops with failing
water level, burner will stop After valve IS
closed and normal operating conditions
restored, burner will resume firing.
4. Be sure that it is the low water cut-off and not
the room thermostat, pressure cut-out.
energy cut-off or other control that has shut
off the burner.
-1 'h _
29'h'
NORMAL
OPERATING
WATER
LEVEL
SKIMMING
WATER
LEVEL
I
COVERED
BUCKET
t
FIGURE B
Left side view 01Malibu models that are equipped with or have pro-
visions for tankless heaters.
5
