Specifications

Catalog 1114-1 SmartSource 2-Stage Water Source Heat Pumps Page 63 of 76
Engineering Guide Specications
Refrigerant Circuit
Units shall have a sealed refrigerant circuit, which includes a non-CFC depleting R-410A refrigerant [rotary (sizes 007-019),
and scroll compressor (sizes 024 to 070)]. In addition, each unit will have a thermostatic expansion valve, an aluminum n
and ried copper tube refrigerant-to-air heat exchanger, a reversing valve and a water-to-refrigerant coaxial heat exchanger.
The coaxial coils shall be made of [copper] [or optional cupronickel] and shall be deeply uted to enhance heat transfer and
minimize fouling and scaling. The coaxial coil shall have a working pressure of 400 psig on the waterside of the unit and 500
psig on the refrigerant side for all R-410A units.
The compressor shall have a dual level vibration isolation system. The compressor will be mounted on vibration isolation
grommets to a heavy gauge compressor mounting plate, which is then isolated from the cabinet base with rubber grommets to
minimize vibration transfer. Compressor shall have thermal overload protection. Compressor shall be located in an insulated
compartment away from air stream to minimize sound transmission.
Refrigerant metering shall be regulated by a thermostatic expansion valve (TXV) only. Reversing valve shall be four-way
solenoid activated refrigerant valve, which fails in the cooling “dominant” operation. Safety controls include a high-pressure
switch, a low-pressure switch, and a low refrigerant temperature sensor. Refrigerant gauge access ttings shall be factory-
installed on high and low pressure refrigerant lines to facilitate eld service. Activation of any safety switch shall prevent the
compressor from operating.
Evaporator coils shall be supplied with an optional corrosion resistant e-coated epoxy coating that must pass a ASTM B-117
1000-hour salt spray test to provide protection against corrosion due to acids, solvents, and salt found in the environment.
Desuperheater
The optional desuperheater (available on units 2 tons or larger) shall be factory-installed in the compressor compartment and
used to add supplemental heating, using superheated refrigerant gas through a tube-in-tube heat exchanger to the domestic
hot water supply. The desuperheater pump shall be factory-installed inside the unit compressor compartment and water lines
shall be fastened to the exterior panel with ush mounted brass NPT ttings.
Hot Gas Reheat Smart Dehumidication Option
The optional factory-installed hot gas reheat coil shall be used as part of a dehumidication operating sequence. Hot gas
reheat shall be enabled when the space humidity level is above a user selectable set point, typically, 50 to 55% RH. Super-
heated refrigerant gas shall be diverted to the reheat coil and unit fan shall operate at dehumidication fan speed upon a call
for dehumidication. This option includes a hot gas reheat coil and a solenoid actuated 3-way valve. Coil shall be proof and
leak tested. A corrosion resistant epoxy coated hot gas reheat coil shall be available as an option.
Simplied Dehumidication Option
Available as a factory-installed option, unit shall be congured to allow for maximum latent capacity while decreasing room
humidity levels by optimizing blower fan speed for dehumidication. Option requires a thermostat with a minimum of 3
cooling stages.
Humidistat Controlled Dehumidication Option
Available as a factory-installed option, unit shall be congured to allow for maximum latent capacity while decreasing room
humidity levels by optimizing blower fan speed for dehumidication. Option requires a humidistat as well as a thermostat
with a minimum of 2 cooling stages.
Dehumidication Always Option
Available as a factory-installed option, for cooling only applications, this option shall utilize a humidistat only. Upon a call
from the humidistat, the unit shall be congured to run at dehumidication blower speed combined with maximum compres-
sor speed, allowing for maximum latent capacity.
Waterside Economizer
A factory mounted and wired waterside economizer shall consist of a hydronic cooling coil located between the unit lter
rack and evaporator, a 2-position 3-way diverting valve, a manual air vent, and an entering uid sensor. The waterside econo-
mizer outer cabinet shall be powder-coat painted with standard color textured paint. The cabinet shall be fabricated from
heavy gauge G-60 galvanized sheet metal with interior surfaces lined with a minimum 3/8-inch thick closed-cell non-brous
IAQ insulation. Components shall be accessible without removing economizer. An insulated stainless steel drain pan compli-
ant with ASHRAE 62.1 including electronic condensate overow protection shall be provided. Economizer ush mounted
piping connections shall be on the same side as the WSHP unit piping connections. Hose kits shall be provided for eld con-
nection of economizer to WSHP unit. For corrosive environment applications, a corrosion resistant epoxy coated coil shall be
available.