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Commercial Heat Pump - Inverter Air-to-Water
Glycol/Water System
Table 3 Glycol Concentrations (10% Minimum, 50% Maximum)
Propylene Glycol % 10 20 30 40 50
Min. Ambient Temp for Operation 26°F/-3°C 18°F/-8°C 8°F/-13°C -7°F/-22°C -29°F/-34°C
Capacity Multiplier 0.99 0.98 0.96 0.93 0.88
Pressure Drop Multiplier (Cooling) 1.10 1.20 1.34 1.5 1.65
Pressure Drop Multiplier (Heating) 1.10 1.20 1.34 1.46 1.5
Minimum Expansion Volume / System Volume
Heating and Cooling 1 gallon expansion per 15 gallons system volume
Heating only, HP only 1 gallon expansion per 20 gallons system volume
Heating only, with Boiler 1 gallon expansion per 15 gallons system volume
Glycol / Water Mixture
The water system must contain a mixture of
inhibited glycol and water with thermal protection
sufcient for the coldest expected temperature for
the installation. The inhibitor level can degrade over
time, and may need to be adjusted periodically.
The inhibitor is essential to prevent the glycol from
accelerating corrosion of metal components in the
system. The glycol and inhibitor levels must be
checked regularly (no less than once annually).
The minimum allowable concentration of glycol is
10% by volume in all installations.
Automotive glycol is not suitable for use in the
system. Over time it may leave deposits which will
degrade the performance and damage pumps or
other devices in the system. Use only propylene
glycol mixtures specically labeled for boiler or HVAC
use.
Obtain all components required for installation (piping, pumping
etc...) and make sure all components and piping comply with
applicable local codes. System uid expansion must be
calculated per established engineering methods.
DO NOT use galvanized pipe anywhere in the system.
Galvanizing will react with the glycol and can cause glycol
degradation and sludge in the system.
Insulate The Piping
1. After testing and draining the system, apply pipe insulation. Fill
system with glycol/water mixture. Calculate the system volume.
2. See Table 3, for required glycol concentration for the minimum
expected outside temperature.
3. Obtain the required volume inhibited glycol/water solution
premixed or mix in a clean container. (The glycol must contain
an inhibitor to prevent metal corrosion.)
4. Pump the glycol/water solution into the system, allowing air
to escape through the purge valve(s).
5. After lling the system, sample the system uid and verify
glycol and inhibitor percentages, following instructions
provided with the glycol.
Installation
Prior to Initial Startup
Before proceeding read and fully understand
the instructions contained in this manual. Do not
attempt to operate this heat pump if it has not been
installed in accordance with the guidelines set forth
in this manual. Failure to comply with this warning
can result in extensive property damage, severe
personal injury or death! Failure to comply can also
void product warranty.
Inspection before turning unit on;
• Check and make sure that the pipe connections are secured,
leak free and the appropriate valves are open.
• Check the water loop to ensure there is sufcient water inside
the expansion tank, the water loop is full of water/glycol mix*
and without any air. Also make sure there is good insulation for
the piping.
• Check all electrical wiring. Make sure that the power voltage
is normal, the wiring is completed per the diagram, and the
ground is connected.
• Ensure air-to-water heat pumps are free of any debris and that
all loose screws or parts have been secured. Once power is
turned on, check controller display for any immediate faults.
A licensed and qualied installer can also verify refrigerant
pressures by using the refrigerant ports located within the unit.
• The ow switch is installed inside of the heat pump. Check to
ensure that the wiring and action of the switch is normal and
controlled by the controller. Flow switch will open at 27 G.P.M.
