Heat Controller
HEV-HEH SEriES
Design Guide
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Heat Controller, LLC
HEV/H SERIES
Engineering Design Guide
Engineering Guide Speci
cations
The coaxial water-to-refrigerant heat exchangers shall be designed
for close approach temperatures and be con struct ed of a convoluted
copper (optional cu pro-n ick el) inner tube and a steel outer tube. The
thermal expansion valves shall provide proper superheat over the
entire
uid temperature range with minimal “hunting”. The valve shall
operate bi-directionally without the use of check valves.
The water-to-re frig er ant heat exchanger and refrigerant suction lines
shall be insulated to prevent condensation at low liquid tem per a tures.
Fan Motor and Blower
The fan shall be a direct drive centrifugal type with a dynamically
balanced wheel. The housing and wheel shall be designed for quiet
low outlet velocity op er a tion and of galvanized steel con struc tion.
Tight fan housing geometry shall not be permitted. The fan housing
shall be removable from the unit without disconnecting the supply
air ductwork for servicing of the fan motor. The fan motor shall be
an ECM variable speed type. The ECM fan motor shall provide soft
starting, maintain constant CFM over its static operating range and
provide air
ow adjustment on its control board. The fan motor shall
be isolated from the housing by rubber grom mets. The motor shall
be permanently lu bri cat ed and have thermal overload protection.
Electrical
The control shall employ quick attach harness as sem blies for low
voltage connections to the control board to aid in troubleshooting
or replacement. An integral terminal block with screw ter mi nals shall
be provided on the control for all field low voltage connections. A
circuit breaker protected 75VA transformer shall be employed. Line
voltage box lugs shall be provided for unit wiring. Units shall have
knockouts for entrance of low and line voltage wiring. The fan motor
and control box shall be harness plug-connected for easy removal.
Piping
Supply and return water connections, as well as Hot Water
Generator (desuperheater) connections shall be 1" [2.5 cm] FPT
(Female Pipe Thread) brass swivel
ttings which provide a union and
eliminate the need for pipe wrenches and sealants when making
eld con nec tions. A thread by sweat
tting shall be provided for
connection to the water heater. All water piping shall be in su lat ed to
prevent condensation at low liquid tem per a tures.
The condensate connection shall be a 3/4" [1.9 cm] MPT.
General
The water source heating/cooling units shall be vertical up
ow air
discharge. Units shall be AHRI/ISO/ASHRAE 13256-1 (ground-
source closed-loop) per for mance cer ti
ed and listed by a nationally
recognized safety-testing lab o ra to ry or agency. Each unit shall be
water run-tested at the factory. Each unit shall be pallet mounted and
shipped with appropriate protective packaging to help avoid damage
in transportation.
Units shall carry a limited express warranty. Refer to the warranty
card shipped with the unit for exact details and instructions on how
to register the product.
The water source units shall be de signed to operate with entering
uid tem per a ture between 20°F and 120°F.
Control
The unit shall have communicating controls, allowing (1) con
guration
and diagnostics on the thermostat (2) monitoring key performance
metrics on the thermostat and (3) a 4-wire connection between the
unit and the thermostat.
Casing & Cabinet
The cabinet shall be fabricated from heavy-gauge galvanized steel and
painted with an epoxy powder coating. The interior shall be insulated
with 1/2" thick, multi-density, coated glass
ber. Insulation in the air
handler section shall be foil backed for ease of cleaning. Two (vertical),
one (horizontal) blower compartment and three compressor
compartment access panels shall be pro vid ed and shall be re mov able
with supply and return ductwork in place. The internal component
layout shall provide for major service with the unit in-place for
re strict ed access installations.
A duct collar (Field installed) shall be provided on the supply air
opening. 1" high ef
ciency MERV 8 pleated
lters shall be provided
with each unit. Units shall have
lter frames. The units shall have
an insulated divider panel between the air handling section and the
com pres sor section to minimize the transmission of compressor
noise, and to permit op er a tion al service testing without air bypass.
Units shall be supplied with left or right air inlet.
Refrigerant Circuit
All units shall contain EarthPure
®
(HFC-410A) sealed re frig er ant
circuit employing a hermetic motor-com pres sor, bidirectional thermal
expansion valve,
nned tube air-to-refrigerant heat exchanger,
reversing valve, coaxial tube water-to-refrigerant heat exchanger and
service ports. An optional Hot Water Generator (desuperheater) coil
shall be provided.
Compressors shall be Next Generation Copeland UltraTech™
Two-Stage scroll type designed for heat pump duty and mounted
on vibration isolators. Compressor motors shall be single phase PSC
with internal over load protection. A factory installed bidirectional
lter drier shall be provided on all models. The
nned tube coil shall
be sized for low-face velocity and constructed of lanced aluminum
ns bonded to ri
ed copper tubes in a staggered pattern not less
than three rows deep. Entire air coil surface shall be tin plated for
corrosion protection.
