Use and Care Manual
32
Burner
Air & Gas
Mixing
Burner
Air & Gas
Mixing
DHW
Plate
Heat
Exchanger
Primary Heat
Exchanger
Secondary Heat
Exchanger
Primary Heat
Exchanger
Secondary Heat
Exchanger
Circulation Pump
Gas
Condensate
Cold Water Inlet
(DHW)
Hot Water Outlet
(DHW)
Pressure Relief Valve
(DHW)
Pressure Relief Valve
for Heating
Circulation Pump
Gas
Condensate
Heating Supply
Heating Return
Auto Feeder
Pressure Relief Valve
for Heating
Auto Feeder
DHW
Plate
Heat
Exchanger
AUTODESK � � � � � � � � � �
AUTODESK � � � � � � � � � �
AUTODESK � � � � � � � � � �
AUTODESK � � � � � � � � � �
Burner
Air & Gas
Mixing
Burner
Air & Gas
Mixing
DHW
Plate
Heat
Exchanger
Primary Heat
Exchanger
Secondary Heat
Exchanger
Primary Heat
Exchanger
Secondary Heat
Exchanger
Circulation Pump
Gas
Condensate
Cold Water Inlet
(DHW)
Hot Water Outlet
(DHW)
Pressure Relief Valve
(DHW)
Pressure Relief Valve
for Heating
Circulation Pump
Gas
Condensate
Heating Supply
Heating Return
Auto Feeder
Pressure Relief Valve
for Heating
Auto Feeder
DHW
Plate
Heat
Exchanger
AUTODESK � � � � � � � � � �
AUTODESK � � � � � � � � � �
AUTODESK � � � � � � � � � �
AUTODESK � � � � � � � � � �
PART 8 – WATER PIPING
[Space Heating Mode] [Domestic Hot Water Mode]
▪ A. GENERAL PLUMBING CONNECTION GUIDELINES
• Pipe material must be suitable to meet local codes and industry standards.
• The pipe must be cleaned and without blemish before any connections are made.
• Do not apply a torch within 12" of the appliance. Doing so could damage the appliance. Such damages ARE NOT covered by product warranty.
• The size of the hot water pipe should be ¾" diameter and the central heating water pipe should be 1" in diameter.
• To ease future maintenance isolation valves are recommended on both the CH and DHW loops.
• All piping should be insulated.
Figure 18 – Operating Description – Water Flow
▪ B. DHW PIPING
▪ C. CENTRAL HEATING PIPING SYSTEM WATER PIPING METHODS
Use both thread tape and pipe dope to connect to the ¾" domestic water inlet and outlet. A shut off valve between the city water supply and DHW
inlet is recommended for ease of service. Rheem offers threaded ¾" Rheem tankless isolation valves with DHW pressure relief valve for ease of
installation and future service. See Optional Equipment, this manual.
It may be recommended to use a back flow preventer – check local codes. If a back flow preventer or a no return valve is used, a thermal
expansion tank must be installed on the cold water supply between the appliance and valve.
EXPANSION TANK AND MAKE-UP WATER
1. Ensure that the expansion tank is designed and sized to correctly handle system water volume and temperature.
WARNING
WARNING
To control thermal expansion, a thermal expansion tank suitable for potable water should be installed in systems with an installed backflow
preventer. DO NOT use a closed type expansion tank. Follow expansion tank manufacturer’s specications to properly size an expansion tank to
the installation. Failure to properly accommodate thermal expansion could result in property damage, severe personal injury, or death.
Expansion tanks must be sized according to total system volume. This includes all length of pipe, all xtures, appliances, etc. Failure to properly
size system expansion could result in wasted time, money, and possible property damage, personal injury, or death.