Hydronic Piping; Special Conditions; Safety Relief Valve And Air Vent - UTICA BOILERS UBSSC-050 Installation, Operation & Maintanance Manual

5.1 General
• Install piping in accordance with authority having jurisdiction.
NOTICE
Use two (2) wrenches when tightening and fi tting
to pipe boiler's threaded fi ttings. Boiler's internal
piping can be damaged if subjected to excessive
torque.
• Support system piping and safety relief valve discharge
piping. Boiler's internal piping and wall mount bracket can
be damaged if subjected to excessive weight.
• Size central heating pump (and domestic hot water pump,
if used) for system requirements only. Heat exchanger
pump compensates for pressure drop through boiler
internal piping and heat exchanger.
• Thoroughly clean and fl ush system before connecting to
boiler.

5.2 Special Conditions

• System piping exposed to freezing conditions: Use
inhibited proplyene glycol solutions certifi ed by fl uid
manufacturer for use with closed water heating system.
Do not use automotive or ethylene glycol.
• Boiler installed above radiation level (or as required by
authority having jurisdiction). Integral low water cutoff
provided in boiler. See page 6.
• Boiler used in connection with refrigeration system.
Install piping in parallel with boiler, with appropriate
valves to prevent chilled medium from entering boiler.
• System piping connected to heating coils located in air
handling unit exposed to refrigerated air circulation.
Install fl ow control valves or other automatic means to
prevent gravity circulation of boiler water during cooling
cycle.

5.3 Safety Relief Valve and Air Vent

NOTICE
Boiler rated at 50 psig (345 kPa) maximum
allowable working pressure. Boiler provided with
30 psig (206 kPa) safety relief valve. Field source
safety relief valve for system pressures greater than
30 psig (206 kPa). Temperature Pressure Gauge
and Air Vent satisfactory for 30-50 psig (206-345
kPa) operation.
• Install safety relief valve and air vent using pipe fi ttings
provided with boiler. See fi gure 5-1
• Install safety relief valve with spindle in vertical position.
• Do not install shutoff valve between boiler and safety
relief valve.
• Install discharge piping from safety relief valve. See

5 - HYDRONIC PIPING

• Poison hazard. Ethylene glycol is toxic. Do not use
ethylene glycol.
• Never use automotive or standard glycol antifreeze,
even ethylene glycol made for hydronic systems.
• Ethylene glycol can attack gaskets and seals used in
hydronic systems.
• Use only inhibited proplyene glycol solutions certifi ed
by fl uid manufacturer as acceptable for use with closed
water heating system.
• Thoroughly clean and fl ush any system that used glycol
before installing new Boiler.
• Provide user with Material Safety Data Sheet (MSDS)
on fl uid used.
Do not expose boiler and condensate piping to
freezing temperatures.
FIGURE 5-1 Safety Relief Valve & Air Vent (View
from front of boiler)
Air Vent
3/4" x 1/4" NPT
90° Elbow
11
WARNING
!
NOTICE
3/4" NPT
Close Nipple
Position Air Vent and Safety Relief Valve
to provide space for discharge piping.
Safety Relief
Valve
3/4"F x 3/4"M
NPT Tee
3/4 NPT