45
3.
Overpressure
(1)
Install a properly sized expansion tank.
(2)
Do not exceed the boiler’s specific
requirements for maximum allowable
working pressure.
(3)
Do not plug or block the relief valve.
4.
Freezing
(1)
Run all portions of the system piping
inside a heated space unless the system
is properly protected with an inhibited
antifreeze solution.
5.
Overheating
(1)
Comply with the boiler’s specific
requirement for minimum water flow
through the boiler. See the
Specifications
Section of this manual.
(2)
Install a low-water cutoff device
whenever the boiler is installed above
the level of the lowest heat emitter
or radiator. Also add a low-water
cutoff when required by local code
requirements.
It is recommended that the LWCO control
is installed above the boiler to provide
the highest level of protection. However,
where the LWCO control is approved
by the LWCO control manufacturer for
installation in a high boiler tapping of a
water boiler, the use of the listed LWCO
control is permitted when it is installed
according to the LWCO manufacturer's
instructions.
6.
Thermal shock
(1)
Do not over-pump. Adhere to the design
flow requirements for each zone.
(2)
Install a boiler bypass, system bypass,
or primary-secondary loop when needed
to avoid returning large volumes of cold
water directly to a hot boiler.
7.
Condensation
(1)
Do not over-pump. Adhere to the design
flow requirements for each zone.
(2)
Adhere to the boiler’s specific
minimum return water and supply water
temperature requirements. Install a
boiler bypass, system bypass, or
primary-secondary loop when needed to
maintain water temperatures and flows
within the specified limits.
(3) Do not allow chilled water to enter the
boiler during the heating cycle, or heated
water to enter chilled water coils during
the cooling cycle.
8.
Dry Fire
Install a low-water cutoff when the boiler
is installed above the level of the lowest
radiator and when required by local code.
9.
Combination Heating and Cooling Systems
If this boiler is used in connection with
refrigeration systems, the boiler must be
installed so that the chilled medium is piped
in parallel with the heating boiler using
appropriate valves to prevent the chilled
medium from entering the boiler, see Figure
D-W1. Also consult Residential Hydronic
Heating Installation and Design I=B=R
Guide.
If this Boiler is connected to heating coils
located in air handling units where they may
be exposed to refrigerated air, the boiler
piping must be equipped with flow control
valves or other automatic means to prevent
gravity circulation of boiler water during the
operation of the cooling system.
10.
Clearance from combustible construction
Maintain minimum 1/2" (13 mm) from hot
water pipes to combustible construction.
APPENDIX D – System Piping (continued)
Figure D-W1: Recommended Piping for
Combination heating & Cooling
(Refrigeration) Systems
