Hydronic Piping; Special Conditions - UTICA BOILERS UBSSC-299 Installation, Operation & Maintenance Manual

Boiler rated at 150 psig (1.03 MPa) maximum
Note
allowable working pressure. Boiler provided with
30 psig (206 kPa) safety relief valve. Field source
safety relief valve for system pressures greater
than 25 psig. Temperature Pressure Gauge
satisfactory for 60 psig operation. Field source
temperature pressure gauge for system pressures
greater than 60 psig.
FIGURE 5-1 Safety Relief Valve & Air Vent (Viewed
from front of boiler)
Position Air Vent and Safety Relief Valve to provide
Note
space for discharge piping.
Safety Relief Safety Relief
Valve Valve
Air Vent Air Vent
3/4" x 1/4" 3/4" x 1/4"
NPT 90° NPT 90°
Elbow Elbow
3/4" x 4 NPT 3/4" x 4 NPT
Nipple Nipple
3/4"F x M x 3/4"F x M x
F NPT Tee F NPT Tee
!
WARNING
• 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 propylene glycol solutions
certified by fluid manufacturer as acceptable for
use with closed water heating system.
• Thoroughly clean and flush any system that used
glycol before installing new Boiler.
• Provide user with Material Safety Data Sheet
(MSDS) on fluid used.

5 - HYDRONIC PIPING

5.1 General
• Install piping in accordance with authority having
jurisdiction.
• 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. Internal
heat exchanger pump compensates for pressure drop
through boiler internal piping and heat exchanger.
• Thoroughly clean and flush system before connecting to
boiler.
• If oil is present in system water, use approved detergent
to wash system.
• Flush system to remove any solid objects such as metal
chips, fibers, or Teflon tape, etc.

5.2 Special Conditions

Note
• System piping exposed to freezing conditions: Use
inhibited propylene glycol solutions certified by fluid
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 pages 10 & 11.
• 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 flow control valves or other automatic means to
prevent gravity circulation of boiler water during cooling
cycle.
14
Do not expose boiler and condensate piping to
freezing temperatures.
PN 240011320 Rev. G 10/01/2021]