Connecting Supply & Return Piping - UTICA BOILERS UH15B Series Installation, Operation & Maintenance Manual

Hydronic Piping - General
• Install piping in accordance with authority having
jurisdiction.
• Support system piping and safety relief valve discharge
piping.
Special Conditions
• System piping exposed to freezing conditions: Use
inhibited proplyene 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). Install low water cutoff.
• Boiler used in connection with refrigeration system.
Install piping in parallel with boiler, with appropriate
valves to prevent chilled medium from entering boiler.
See Figure 2, Page 10.
• 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.
Safety Relief Valve Installation
!
WARNING
Burn and scald hazard. Safety relief valve could
discharge steam or hot water during operation.
Install discharge piping per these instructions.
NOTICE
Boiler rated at 100 psig maximum allowable working
pressure. Boiler provided with 30 psig safety relief
valve. Field source safety relief valve for system
pressures greater than 30 psig. Temperature-
pressure gauge provided with boiler is satisfactory
for 30-50 psig operation. Replace temperature-
pressure gauge for system pressure over 50 psig.
Scale on dial must be graduated to not less than 1½
nor more than 3½ time safety relief valve pressure
settings.
5 - CONNECTING SUPPLY & RETURN PIPING
• Do not install shutoff valve between boiler and safety
relief valve.
• Systems with automatic fill valves require back flow
prevention device.
• Install discharge piping from safety relief valve. See
Warning, Page 8.
• When boiler is connected to heating system utilizing
multiple zoned circulators, each circulator must be
supplied with flow control valve to prevent gravity
circulation.
• Hot water boilers and system must be filled with water
and maintained to minimum pressure of 12 psi.
• Bypass piping is an option which gives ability to adjust
the supply boiler water temperature to fit the system or
condition of installation. This method of piping, however,
is not typically required for baseboard heating systems.
Typical installations where bypass piping is used are as
follows:
A. This method is used to protect boilers from
condensation forming due to low temperature
return water. Generally noticed in large converted
gravity systems or other large water volume
systems. Figures 3 & 4, Page 11.
B. These methods are used to protect systems using
radiant panels and the material they are encased
in from high temperature supply water from the
boiler and protect boiler from condensation.
NOTE#1: When using bypass piping, adjust valves V1 & V2
until desired system temperature is obtained.
NOTE#2: Bypass loop must be same size piping as the
supply and return piping.
• Installation using circulators and zone valves are shown
in Figures 3-8 . For further piping information refer to
AHRI Installation and Piping Guide.
• For zone controls and indirect hot water, refer to
appropriate manufacturer instructions.
8
PN 240011107, Rev. E [06/15/2018]