10
110891-02 - 5/22
RSAH
Installation & Service Manual
Figure 3-1: Recommended Piping for Combination
Heating and Cooling (Refrigeration) System
A. DESIGN A PIPING SYSTEM and install boiler
which will prevent oxygen contamination of boiler
water and frequent water additions.
1. There are many possible causes of oxygen
contamination such as:
a. Addition of excessive make-up water as a
result of system leaks.
b. Absorption through open tanks and fittings.
c. Oxygen permeable materials in the
distribution system.
2. In order to insure long product life, oxygen
sources should be eliminated. This can be
accomplished by taking the following
measures:
a. Repairing system leaks to eliminate the
need for addition of make-up water.
b. Eliminating open tanks from the system.
c. Eliminating and/or repairing fittings which
allow oxygen absorption.
d. Use of non-permeable materials in the
distribution system.
e. Isolating the boiler from the system water by
installing a heat exchanger.
3. Connect System supply and return piping to
boiler. See Figures 3-3 and 3-4. Also, consult
I=B=R, “Residential Hydronic Heating
Installation and Design Guide”. Maintain
minimum ½ inch clearance from hot water
piping to combustible materials.
WARNING
System supply and return piping must be
connected to correct boiler pipe.
U.S. Boiler Company recommends sizing the
system circulator to supply sufficient flow (GPM)
to allow a 20°F temperature differential in the
system. When sizing the system circulator, the
pressure drop of all radiators, baseboard and
radiant tubing and all connecting piping must
be considered.
a. 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
3-1. Also, consult I=B=R, “Residential
Hydronic Heating Installation and Design
Guide”.
b. 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 to prevent gravity circulation of boiler
water during the operation of the cooling
system.
c. If boiler is used with an Indirect-Fired
Domestic Water Heater, install the Indirect-
Fired Domestic Water Heater as a separate
heating zone. Refer to the Indirect-Fired
Domestic Water Heater Installation,
Operating, and Service Instructions for
additional information.
3
Water Piping and Trim
!
WARNING
Failure to properly pipe boiler may result in improper operation and damage to boiler or structure.
Oxygen contamination of boiler water will cause corrosion of iron and steel boiler components, and can
lead to boiler failure. -U.S.Boiler Company’s Standard Warranty does not cover problems caused by oxygen
contamination of boiler water or scale (lime) build-up caused by frequent addition of water.
!
