Xylem MM 221G Models 157S RBP MD Low Water Cut-Offs/Pump Controllers - Manual (Page 7)

STEP 4 - Testing
Standby Range Operation:
7
OFF
ON
a. Turn on the electric power to the boiler. The pump should go
on and the burner must remain off.
b. The boiler should begin to fill with water. As the water
level rises in the sight glass, the burner should turn on
and then the pump should turn off.
If the burner does not turn on or pump turn off at appro-
priate levels, immediately turn off the boiler and make
the necessary corrections.
c. Blow down the control when the water in the boiler is at
its normal level and the burner is on. Slowly open the
upper then the lower blow-down valves and observe the
water level fall in the sight glass. Close the valves (lower
first then upper) after verifying that the pump contacts
have closed and the burner shuts off. If this does not
happen, immediately shut off the boiler, correct the
problem and retest.
IMPORTANT: Follow the boiler manufacturer’s start-up and operating instructions along with all applicable
codes and ordinances.
This control is factory calibrated for specific level set-
tings as shown on page 2 in the "Operation" section. The following testing procedure is only meant to
serve as a verification of proper operating sequence.
If the burner comes on, immediately turn the boiler off and make the
necessary corrections.
Failure to follow this warning could cause an explosion or fire and
result in property damage, personal injury or death.
! WARNING
To prevent serious personal injury from steam pipe blow down, connect a
drain pipe to the control opening to avoid exposure to steam discharge.
Failure to follow this caution could cause personal injury.
! CAUTION
INSTALLATION COMPLETE