2
Switch
Initial
Initial
Dwell/Feed
Position
Dwell
Feed
Cycles
M&M
60
60
Repeats until
seconds
seconds
LWCO is satisfied
2
90
90
One
seconds
seconds
3
100
100
One
seconds
seconds
2 3
M&M
M&M
2
3
SPECIFICATIONS
OPERATION
Maximum Water Pressure:
150 psi (10.5 kg/cm
2
)
Maximum Boiler Pressure:
15 psi (1 kg/cm
2
)
Maximum Boiler Size:
2000 sq. ft. EDR
500,000 BTU/hr output capacity
Maximum Water Temperature:
175˚F (79˚C)
Maximum Ambient Temperature:
100˚F (38˚C)
Maximum Power Consumption (during water feed only):
15 VA @ 24 VAC
20 VA @ 120 VAC (50 or 60 Hz)
Pipe Connections:
3/8" NPT (sweat adapters included for connection to 1/2" copper pipe)
Flow Data:
2 gpm (7.6 lpm) standard
Orifices included to change feed rate to 1 gpm (3.8 lpm) or 4 gpm (15.1 lpm)
The Uni-Match water feeders have a three-position
slide switch which initiates a dwell period specific
to the position of the switch. If the return conden-
sate satisfies the low water cut-off (LWCO) during
the dwell period, no water will be added to the
boiler. Once the dwell period has passed, the
feeder will be activated and water will be added to
the boiler. The feeder will be deactivated when the
LWCO has been satisfied.
When controlled by a LWCO with a delay-on-make
(DOM) feature, such as the 15 second delay on
the PS-801 and PS-802, the water level in the
boiler will be restored to a level up to 1" above the
level of the probe. This lessens the chances of
overfeeding, which can result in damage to the
boiler.
The position of the slide switch also dictates the
length of the dwell period, the length of time valve
is open and the number of dwell/feed cycles. The
control is set with the slide switch in position 3 and
can be changed in the field after installation. The
chart on the right indicates the cycles and length
of dwell/feed cycles for each position.
