P.33
Circulator Pump
The circulator pump shall be a wet rotor small circulator with a cast iron, stainless steel,
brass or polymer body and a metal or polymer impeller. The pump motor shall be
induction or permanent magnet ECM driven. The pump shall be rated for: maximum fluid
temperatures of no less than 180
o
F and pressures of no less than 125 PSI. The maximum
rated amperage shall be no more than 1.5 Amps and the maximum rated power draw shall
be no more than 135 Watts.
Expansion Tank
The expansion tanks shall be rated for non-potable propylene glycol based heat transfer
fluids. The maximum working temperature shall be no less than 180
o
F and the maximum
working pressure shall be no less than 75 psi. The expansion tank volume shall be not less
than 2.0 gallons and the acceptance volume shall be not less than 1.0 gallon.
Heat Transfer Fluid
The heat transfer fluid shall be buffered propylene glycol based and shall have a maximum
operating temperature of no less than 280
o
F. If the HTF has a measurable flash point, at
the concentrations used in the system, the HTF shall have a flash point of 400
o
F or higher.
Thermostatic Mixing Valve
The thermostatic mixing valve shall have a bronze, brass or stainless steel body with a
rated maximum working temperature no less than 200
o
F and a rated maximum working
pressure no less than 125psi. The range of temperature set points shall be at least 18ºF
(10ºC) and shall include a set point of 120ºF (50ºC). The Thermostatic Mixing valve shall
be third party listed and certified to one of the following ASSE standards: ASSE 1016;
ASSE 1017; ASSE 1070.
Ball Valves
Ball valves shall be of bronze, brass or stainless steel construction. Maximum working
temperature shall be no less than 200
o
F and maximum working pressure shall be no less
than 125 psi.
Three-Way Valves (Optional)
Three-Way valves shall be of bronze, brass or stainless steel construction. Maximum
working temperature shall be no less than 200
o
F and maximum working pressure shall be
no less than 125 psi.
Boiler Drains
(A.K.A. Charge Valves; Fill Valves; Drain Valves; Purge Valves)
Boiler Drains shall be of bronze, brass or stainless steel construction. Maximum working
temperature shall be no less than 200
o
F and maximum working pressure shall be no less
than 125 psi.
Pressure Relief Valve
The pressure relief valve shall be of bronze, brass or stainless steel construction with a
pressure setting between 30psi and 150psi. The pressure relief valve shall be set to
discharge at a pressure below the maximum design pressure of all other components in the
collector loop.
Check Valve
(A.K.A. Non-Return Valve)
The check valve may be a stand alone component or may be integral to the circulator
pump. The check valve shall be spring type of bronze, brass or stainless steel or polymer
construction. Maximum working temperature shall be no less than 200
o
F and maximum
working pressure shall be no less than 125 psi.
Air Vent
The air vents shall be of bronze, brass or stainless steel construction. Maximum working
temperature shall be no less than 200
o
F and maximum working pressure shall be no less
than 125 psi.
Appendix A
