101
110331-07 - 8/23
PHTM II
Combi Installation, Operating & Service Instructions
Appendix A
Combination Refrigeration/Heating System
1. If boiler is used in connection with refrigeration
systems, boiler must be installed with chilled
medium piped in parallel with the heating boiler
using appropriate valves to prevent chilled
medium from entering boiler. See Figure A-1. Also
consult Residential Hydronic Heating Installation
and Design I=B=R Guide.
Water
Chiller
Shut-off
Valves
Expansion
Tank
Circulator
Shut-off
Valves
Supply main to
combined heating
& cooling system
Return main from
combined heating
& cooling system
2. If boiler is connected to heating coils located in
air handling units where they may be exposed to
refrigerated air, boiler piping must be equipped
with flow control valves or other automatic means
to prevent gravity circulation of boiler water during
operation of cooling system.
Figure A-1: Isolated Boiler from Refrigeration System