Bell & Gossett V59075B Low Flow Model UBYL Y-Strainer Combination Valve - Manual (Page 3)

Read the differential pressure from the coil inlet
isolation valve (typically a strainer) to coil outlet
isolation valve (typically a flow limiting balancing valve).
The differential value minus the pressure drops across the
coil and installed control valves should be less than 60 psi
for proper flow control.
WARNING: Hot water leakage can occur
from readout valves (P/T ports) during probe
insertion and during hookup of readout kit.
Follow the instruction manuals supplied
If Y-strainer pressure drop becomes excessive,
accumulated dirt and contaminants should be blown
through the blow-down line (if installed) to a drain. If a
blow-down line is not installed, see the service
instructions for removing and cleaning the strainer. The
Y-strainers have construction with an integrated ball valve
and will function as a service valve.
SERVICE INSTRUCTIONS
If excessive pressure drop is noted across the Y-Strainer,
the internal strainer has most likely collected a lot of dirt
or debris and needs to be cleaned. Install blow-down line
(hose) to the drain valve on the strainer chamber then
open the drain valve. If flushing the strainer at this point
has not solved the pressure drop problem, the Y-strainer
must be disassembled and strainer to be cleaned.
To clean the strainer, isolate the Y-Strainer from the
system with the integral ball valve on the upstream side
of the strainer. Use an isolation valve downstream of the
strainer and coil to further isolate the system. Allow the
system to cool to 100°F (38°C) or less before handling.
Proceed to drain the isolated system through the drain
valve in the Y-Strainer.
WARNING: Corrosion or leakage are
indications that the Low Flow Model UBYL
Y-Strainer Valve must be replaced. Failure to
follow these instructions could result in
serious personal injury or death and property damage.
Before system start up, flush the hydronic system as part
of commissioning. Make sure the valve cap and drain is
tightened properly. Start the system and inspect the Low
Flow Model UBYL Y-strainer valve for leakage.
HOW TO USE PRESSURE TAPS (P/T PORTS) TO MEASURE
SYSTEM OPERATING CONDITIONS
Using Bell & Gossett Model RP-250B, readout probes,
attach Bell & Gossett differential pressure readout kit to
the readout valves (P/T ports) on the Low Flow Model
UBYL Y-Strainer Valves.
with readout probes and readout kits for safe use.
Failure to follow these instructions could result in
serious personal injury or death and property damage.
Installed P/T Port
Isolation Valve
Strainer