
42
MUL
TI V W
ater Mini System Installation Manual
Due to our policy of continuous product innovation, some specifications may change without notification.
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Expansion Tank
All closed loop systems should have a bladder type expansion tank installed. The expansion tank will protect the equipment from excess
pressures due to expansion and contraction of water in the loop as the temperature changes.
Heat Source and Storage Tank
There are several sources for heat that can be used for this system. They include the following:
• Electric boiler
• Gas boiler
• Solar heat with storage tanks
• Ground source heat
• Steam heat from remote central plant
To deal with thermal flux of the system, if floor space is allowed, a heat storage tank can be installed. The heat storage tank can store
surplus heat or store heat at nighttime when electric rates are lower. Closed type storage tanks are recommended to prevent contamination
of the water system.
WATER CIRCUIT INSTALLATION
Geothermal Water Circuit Design
In lieu of a cooling tower / boiler, Multi V Water Mini units may use a geothermal system that is properly sized to match the water cooled unit
capacity. This year round heating and cooling system will utilize a two (2) pipe closed loop water circuit that circulates water continuously,
maintaining water temperatures between 23°F and 113°F for heating, 50°F and 113°F for cooling. When the Multi V Water Mini unit is in
cooling mode, heat is rejected to the geothermal system. When the Multi V Water Mini unit is in heating mode, heat is absorbed from the
geothermal system.
Multi V Water Mini units have factory-installed stainless steel plate heat exchangers. To protect these heat exchangers, it is recommended to
use closed geothermal water loops. Should open geothermal systems be used, an intermediate heat exchanger should be installed to isolate
Multi V Water Mini units from contaminants in the water system. Open geothermal loops may contain minerals, biological contaminants,
corrosive agents, or other substances which can cause scale, fouling or corrosion, that could degrade performance or shorten the life of the
heat exchanger and unit.
Antifreeze can be used for all geothermal applications. Refer to antifreeze information on page 44 for recommended levels of antifreeze and
correction factors.
Figure 43: Open-Type and Closed-Type Tower Design Schematic.
Water Circuit Design
When using an open cooling tower or open geothermal wells, an intermediate heat exchanger is recommended to be installed to protect the water
source unit from contamination.
Note:
Open-Type
Cooling Tower
First Side Second
Heat Exchanger
Side
Closed-Type
Cooling Tower
Open-Type Cooling Tower + Heat Exchanger
Heat exchanger is installed between the cooling tower and water
source unit system piping, and the temperature difference between
the first and second sides is maintained constantly.
Closed-Type Cooling Tower
Heat-source water of the cooling tower is supplied directly to the
water source unit system.