Part Number 550-110-641/0605
9
PFG SerieS 7 GaS-Fired Water Boiler — Boiler Manual
External heat exchangers
The PFG boiler can be used with a storage tank/heat exchanger unit for
domestic hot water. The boiler/tank combination should be installed and
wired in accordance with the tank manufacturer’s instructions, which will
also show any additional components required. A zone valve or separate
circulator must be installed to regulate the production of hot water.
Freeze protection
Use antifreeze especially made for hydronic systems. Inhibited propylene
glycol is recommended.
Do not use automotive, ethylene glycol or undiluted antifreeze.
Severe personal injury, death or substantial property damage
can result.
50% solution provides protection to about -30°F
Local codes may require a back-flow preventer or actual disconnect from
city water supply.
Determine quantity according to system water content. Boiler water content
is listed on page 23.
Follow antifreeze manufacturer’s instructions.
Using with refrigeration system
The boiler must be installed so that chilled medium is piped in parallel with
the heating boiler with appropriate valves to prevent the chilled medium
from entering the boiler. Consult I=B=R Installation and Piping Guides.
If boiler is connected to heating coils located in air handling units where they
can be exposed to refrigerated air, gravity circulation during the cooling cycle
must be prevented with flow control valves or other automatic means.
