Floa t switch adjustment – Bell & Gossett DN0147D HS Underground Condensate and Boiler Feed Units Series UHM User Manual
Page 3
OPEN VENT
TO DRAIN
WATER MAKE-UP
SUPPLY
GV
Y STRAINER
SOLENOID VALVE
CV
DISPLACER SWITCH TO
ACTUATE VACUUM PUMP
FOR OVERFLOW CONTROL
BASKET STRAINER
RETURN LINE
GV
GV
GV
U
U
U
U
CV
PC
VACUUM TIGHT UNDERGROUND BOILER FEED UNIT TYPE CMVU
CV
PUMP MOTOR ACTUATED BY
BOILER WATER LEVEL CONTROLLER
THERMOSTATIC TRAP OPTIONAL
GV
EQUALIZING LINE
TO BOILER
AIR AND EXCESS WATER
SUCTION LINE TO
VACUUM PUMP
PUMP DISCHARGE
IDPD55
PUMP DISCHARGE
IDPD54
AIR SUCTION LINE
TO VACUUM PUMP
EQUALIZING LINE
TO SUPPLY SIDE
OF SYSTEM
PC
GV
GV
CV
U
THERMOSTATIC TRAP OPTIONAL
PUMP MOTOR ACTUATED BY
FLOAT SWITCHES
CV
GV
U
CV
DISPLACER SWITCH
TO ACTUATE PUMP
BASKET
STRAINER
GV
OPEN VENT
TO DRAIN
RETURN LINE
VACUUM TIGHT UNDERGROUND CONDENSATION PUMP TYPE CVU
LEGEND
CV - CHECK VALVE
GV - GATE VALVE
PC - PLUG LOCK
U - UNION
3
FLOA
T SWITCH ADJUSTMENT
The float positions are factory set. These positions should be
reset as necessary. Minor deviation is permissible to meet
local requirements. The settings must avoid “short cycling” of
the pumps.
The float switch and mechanical alternator each have an inter-
nal compensating spring to balance the weight of the float
guide rod. These springs are to have just enough tension or
compression on the float switch to counterbalance the guide
(but not the float).
PIPING DIAGRAMS V
ACUUM TIGHT
UNDERGROUND CONDENSATE &
BOILER FEED UNITS
Type CVU units are designed for use as a mechanical lift in a
vacuum heating system. They are also used to return conden-
sate under vacuum to a boiler feed tank. They have vacuum
tight displacer switch(es) for pump control.
Type CMVU units have water make-up valve and are actuated
by boiler controller. They are designed for use in a vacuum
system to discharge condensate directly to the boiler.
It is necessary to pipe the vent line to atmosphere using full
vent port size piping with check valves installed as shown on
diagrams. It is also recommended that the vent line be
“dripped” to drain to prevent an accumulation of condensate
in the vent pipe.
MECHANICAL
ALTERNATOR
* MAKE SETTINGS
WITH ARM AT
HIGHEST POSITION
FLOAT SWITCH
PIPING DIAGRAM FOR UNDERGROUND
CONDENSATE UNIT USED
IN A VACUUM SYSTEM
PIPING DIAGRAM FOR UNDERGROUND
BOILER FEED UNIT USED
IN A VACUUM SYSTEM
FLOAT SETTING CHART
Condensate Unit
Single
Duplex
Duplex 2 Float Switch
Boiler
Primary
Stand-By
Feed
Unit
(Mech. Alt.)
Float Switch
Float Switch
Unit
Depth
“A”
“B”
“A”
“B”
“A”
“B”
“A”
“B”
“A”
“B”
36"
11"
22"
8
1
/
2
"
21" 12
1
/
2
" 22"
11"
22"
14"
22"
48"
11"
34"
8
1
/
2
"
33" 12
1
/
2
" 34"
11"
34"
26"
34"
2DFS01
COMPENSATING
SPRING ADJUSTER
FLOAT GUIDE
“A”
“B”
FLOAT GUIDE
COMPENSATING
SPRING ADJUSTERS
IDPD55