Specifications

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ENVISION COMMERCIAL SPECIFICATION CATALOG
• Closed Loop/Ground Water Plate Heat Exchanger
Systems utilize lake, ocean, well water or other water
sources to maintain closed loop water temperatures in
multi-unit Envision systems. A plate frame heal exchanger
isolates the units from any contaminating effects of the
water source, and allows periodic cleaning of the heat
exchanger during off peak hours.
Operation and benefits are similar to those for ground-
source systems. Due to the extended loop temperatures,
AHRI/ISO 13256-1 Ground Loop Heat Pumps are required
for this application. Closed loop plate heat exchanger
systems are applicable in commercial, marine, or industrial
structures where the many benefits of a water source heat
pump system are desired, regardless of whether the load is
heating or cooling dominated.
Because auxiliary equipment such as a fossil fuel boiler
and cooling tower are not required to maintain the loop
temperature, operating and maintenance costs are very
low. Ground-source systems are most applicable in
residential and light commercial buildings where both
heating and cooling are desired, and on larger envelope
dominated structures where core heat recovery will not
meet overall heating loads. Both vertical and horizontally
installed closed-loops can be used. The land space
required for the "heat exchangers" is 100-250 sq. ft./ton
on vertical (drilled) installations and 750-1500 sq. ft./ton
for horizontal (trenched) installations. Closed loop heat
exchangers can be located under parking areas or even
under the building itself.
On large multi-unit systems, sizing the closed loop heat
exchanger to meet only the net heating loads and assisting
in the summer with a closed circuit cooling tower may be
the most cost effective choice.
• Closed Loop/Ground-Source Surface Water Systems
also utilize the stable temperatures of Surface Water to
maintain proper water source temperatures for Envision
Series extended range heat pump systems. These systems
have all of the advantages of horizontal and vertical closed
loop systems. Due to the extended loop temperatures,
AHRI/ISO 13256-1 Ground Water or Ground Loop Heat
Pumps are required for this application.
In cooling dominated structures, the ground-source surface
water systems can be very cost effective especially where
local building codes require water retention ponds for
short term storage of surface run-off. Sizing requirements
for the surface water is a minimum of 500 sq. ft./ton of
surface area at a minimum depth of 8 feet. WaterFumace
should be contacted when designs for heating dominated
structures are required.
Envision Application Notes cont.
Surface Water - Closed Loop/Ground Source
Plate Heat Exchanger - Closed Loop/Ground Water