Application Central
Considerations Pumping
System
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Figure 10: Central pumping system installation
General
A central pumping system involves
asingle pump design usually locat- ed within a basement or mechanical room to fulfill pumping requirements for the entire building system. With a central pumping system, an auxil- iary pump is typically applied to lessen the likelihood of system
(See Figure 10 for unit installation of a central pumping system).
Central Pump
Application
Ball valves should be installed in the supply and return lines for unit isolation and unit water flow rate balancing (if an auto- matic flow device is not selected). This connection, along with hoses, are also rec- ommended for backflushing and chemical cleaning of the water to refrigerant heat exchanger.
Flexible hoses may be used to connect the water supply and return lines to the water inlets and outlets. These hoses reduce possible vibration between the unit and the rigid system.
Note: Hoses and or pipes should be made of braided stainless steel, and sized suit- ably for the systems water pressure and flow rate.
Load side connections are typically used to supply the ter-
minal devices with 45 F or 120 F fluid.
The sound attenuation pad should be slightly oversized for unit. This field supplied product is recommended for sound absorption of unit.
The low voltage control con- nection provided on the unit is large enough for attaching con- duit.
The central systems supply and return lines should be sized to handle the required flow with a minimum pressure drop.
Note: Pipe will sweat if low temperature water is run through the supply or return lines. Trane recommends that these lines be insulated to pre- vent damage from condensa- tion.
The field supplied line voltage disconnect should be installed for branch circuit pro- tection. The unit is supplied with an opening for attaching conduit.
