Install Instructions

54
APPENDIX D – System Piping (continued)
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
ow 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
ow requirements for each zone.
(2) Adhere to the boiler’s specic
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 ows
within the specied 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.
i
The following system diagrams are intended to provide a minimum level of guidance for a
successful and trouble-free installation of the boiler in common applications. They do not substitute
for proper design, evaluation, and installation by a trained and qualified installer using the proper
tools, techniques, and design expertise. Not all options are available with every boiler.
Figure D-1: Recommended Piping for Combination
Heating & Cooling (Refrigeration) Systems
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 or other automatic means
to prevent the chilled medium from entering
the boiler, see Figure D-1. 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 ow control
valves or other automatic means to prevent
gravity circulation of boiler water during
cooling cycle.