Water Furnace NSKW06 Service manual

IM2566WN 07/16
Installation Information
Water Piping Connections
Electrical Data
Startup Procedures
Preventive Maintenance
Versatec Ultra NSKW Installation Manual
Geothermal Hydronic Heat Pump
NSKW

VERSATEC ULTRA NSKW INSTALLATION MANUAL
Table of Contents
Model Nomenclature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
General Installation Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
Water Quality . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Field Connected Water Piping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7-9
Potable Water Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10-11
Hydronic Section . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12-13
Accessories and Options. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Electrical Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14-15
Wiring Schematics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .16-19
External Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .20
Converting to a Dedicated Cooling Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
Unit Startup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
The Aurora Base Control System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22-25
Reference Calculations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .26
Legend and Notes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Pressure Drop . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Operating Limits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27
Physical Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Flow Rates . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
Thermistor Resistance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Operating Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .29
Antifreeze Correction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .30
Troubleshooting Guideline for Refrigerant Circuit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
HR Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32-32
HE Data. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .34-35
DHW HE Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
Heating and Cooling Cycle Analysis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37
Troubleshooting Form . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38
Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .39
Preventive Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
Service Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 41
Technical Documentation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42-45
Revision Guide. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 47

4
VERSATEC ULTRA NSKW INSTALLATION MANUAL
Model Nomenclature
NSKW 08 H 6 0 A C
1-4 5-6 7 8 9 10 11
Model
NSKW –Versatec Hydronic
Heat Pump
Unit Capacity
06, 08, 12, 17
Reversible Option
H- Heating Only
R- Reversible
Voltage
6–220-240/50/1
7–380-420/50/3
Hot Water Option1
0 – No Hot Water Generation, No IntelliStart
2 – Hot Water Generation, No IntelliStart
3 – No Hot Water Generation, IntelliStart
5 – Hot Water Generation, IntelliStart
Vintage
*–Factory Use Only
Future Option
SS –Standard Option
Load Coax2
C–Copper
N - Cupronickel
Source Coax
C–Copper
N–Cupronickel
Controls Option
A– Aurora™ Base Controls (ABC)
Rev.: 15 June 2016
C
12
NOTES: 1 – Available on 08, 12, 17 only. Hot water generator requires field installed external pump kit.
2 – NSKW06 heating only models are available only with copper double wall vented load coax for potable water,
and are not designed to be converted to dedicated cooling units.
SS *
13-14 15
All Versatec Ultra NSKW product is safety tested to CE standards and
performance tested in accordance with standard BS EN 14511-2.
Supplier WaterFurnace International, Inc.
Model NSKW06 NSKW08 NSKW12 NSKW17
Model hot water heater - - - -
Temperature application °C 35 55 35 55 35 55 35 55
Declared load profile for water heating - - - -
Seasonal space heating energy efficiency class, average climate A++ A++ A++ A++ A++ A++ A++ A++
Water heating energy efficiency class, average climate - - - -
Rated heat output (Pdesignh), average climate kW 6 8 12 17
Annual energy consumption space heating, average climate kWh 2,860 3,432 3,689 4,543 4,920 6,343 7,985 9,656
Annual energy consumption water heating, average climate kWh - - - -
Seasonal space heating energy efficiency, average climate % 160 119 178 132 187 137 164 126
Water heating energy efficiency, average climate % - - - -
Sound power level LWA indoors dB 57 57 61 63
Rated heat output (Pdesignh), cold climate kW 6 8 12 17
Rated heat output (Pdesignh), warm climate kW 6 8 12 17
Sound power level LWA outdoors dB dB - - - -
3/18/2016
Energy Labelling

5
VERSATEC ULTRA NSKW INSTALLATION MANUAL
Safety Considerations
Installing and servicing air conditioning and heating
equipment can be hazardous due to system pressure and
electrical components. Only trained and qualified service
personnel should install, repair or service heating and air
conditioning equipment. When working on heating and
air conditioning equipment, observe precautions in the
literature, tags and labels attached to the unit and other
safety precautions that may apply.
Follow all safety codes. Wear safety glasses and work
gloves. Use quenching cloth for brazing operations. Have
fire extinguisher available for all brazing operations.
NOTE: Before installing, check voltage of unit(s) to ensure
proper voltage.
WARNING: Before performing service or
maintenance operations on the system, turn off
main power switches to the unit. Electrical shock
could cause serious personal injury.
Process Water Applications
For process water applications, it is recommended that
a secondary load heat exchanger be installed to prevent
corrosion to the unit’s primary coaxial coil. In situations
where scaling could be heavy or where biological growth
such as iron bacteria will be present, a closed loop system is
recommended. Over a period of time, ground water unit heat
exchanger coils may lose heat exchange capability due to a
buildup of mineral deposits. These can be cleaned only by
a qualified service mechanic as special pumping equipment
and solutions are required. Never use flexible hoses with a
smaller inside diameter than that of water connections.
Moving and Storage
Move units in the normal “Up” orientation as indicated by
the labels on the unit packaging. When the equipment
is received, all items should be carefully checked against
the bill of lading to ensure that all crates and cartons
have been received in good condition. Examine units for
shipping damage, removing unit packaging if necessary
to properly inspect unit. Units in question should also
be internally inspected. If any damage is observed, the
carrier should make the proper notation on delivery receipt
acknowledging the damage. Units are to be stored in a
location that provides adequate protection from dirt, debris
and moisture.
General Installation Information
WARNING: To avoid equipment damage, do not
leave the system filled in a building without heat
during cold weather, unless adequate freeze
protection levels of antifreeze are used. Heat
exchangers do not fully drain and will freeze
unless protected, causing permanent damage.
Unit Location
Provide sufficient room to make water and electrical
connections. If the unit is located in a confined space,
provisions must be made for unit servicing. Locate the
unit in an indoor area that allows easy removal of the
access panels and has enough space for service personnel
to perform maintenance or repair. These units are not
approved for outdoor installation and, therefore, must be
installed inside the structure being conditioned. Do not
locate units in areas subject to freezing conditions.
WARNING: Do not store or install units in
corrosive environments or in locations subject
to temperature or humidity extremes (e.g. attics,
garages, rooftops, etc.). Corrosive conditions and
high temperature or humidity can significantly
reduce performance, reliability, and service life.
Mounting Units
Prior to setting the unit in place, remove and discard the
compressor hold down shipping bolt located at the front of
the compressor mounting bracket.
Units should be mounted level on a vibration absorbing pad
slightly larger than the base to provide isolation between
the unit and the floor. It is not necessary to anchor the unit
to the floor. Allow access to the front, back, and side access
panels for servicing.
Vibration Pad Mounting

6
VERSATEC ULTRA NSKW INSTALLATION MANUAL
General
Water-to-water heat pumps may be successfully applied
in a wide range of residential and light commercial
applications. It is the responsibility of the system designer
and installing contractor to ensure that acceptable water
quality is present and that all applicable codes have been
met in these installations. Failure to adhere to the guidelines
in the water quality table could result in loss of warranty.
Application
These heat pumps are not intended for direct coupling
to swimming pools and spas. If used for this type of
application, a secondary heat exchanger must be used.
Failure to supply a secondary heat exchanger for this
application will result in warranty exclusion for primary heat
exchanger corrosion or failure.
Water Treatment
Do not use untreated or improperly treated water.
Equipment damage may occur. The use of improperly
treated or untreated water in this equipment may result in
scaling, erosion, corrosion, algae or slime. The services of a
qualified water treatment specialist should be engaged to
determine what treatment, if any, is required. The product
warranty specifically excludes liability for corrosion,
erosion or deterioration of equipment.
Water Quality
The heat exchangers and water lines in the units are copper
or cupronickel tube. There may be other materials in the
building’s piping system that the designer may need to take
into consideration when deciding the parameters of the
water quality.
If an antifreeze or water treatment solution is to be used,
the designer should confirm it does not have a detrimental
effect on the materials in the system.
Contaminated Water
In applications where the water quality cannot be held to
prescribed limits, the use of a secondary or intermediate
heat exchanger is recommended to separate the unit from
the contaminated water.
The following table outlines the water quality guidelines
for unit heat exchangers. If these conditions are exceeded,
a secondary heat exchanger is required. Failure to supply
a secondary heat exchanger where needed will result in a
warranty exclusion for primary heat exchanger corrosion
or failure.
WARNING: Must have intermediate heat
exchanger when used in pool and spa
applications.
Material Copper 90/10 Cupronickel 316 Stainless Steel
pH Acidity/Alkalinity 7 - 9 7 - 9 7 - 9
Scaling Calcium and
Magnesium Carbonate
(Total Hardness)
less than 350 ppm
(Total Hardness)
less than 350 ppm
(Total Hardness)
less than 350 ppm
Corrosion
Hydrogen Sulfide Less than 0.5 ppm (rotten egg
smell appears at 0.5 ppm) 10 - 50 ppm Less than 1 ppm
Sulfates Less than 125 ppm Less than 125 ppm Less than 200 ppm
Chlorine Less than 0.5 ppm Less than 0.5 ppm Less than 0.5 ppm
Chlorides Less than 20 ppm Less than 125 ppm Less than 300 ppm
Carbon Dioxide Less than 50 ppm 10 - 50 ppm 10 - 50 ppm
Ammonia Less than 2 ppm Less than 2 ppm Less than 20 ppm
Ammonia Chloride Less than 0.5 ppm Less than 0.5 ppm Less than 0.5 ppm
Ammonia Nitrate Less than 0.5 ppm Less than 0.5 ppm Less than 0.5 ppm
Ammonia Hydroxide Less than 0.5 ppm Less than 0.5 ppm Less than 0.5 ppm
Ammonia Sulfate Less than 0.5 ppm Less than 0.5 ppm Less than 0.5 ppm
Total Dissolved Solids (TDS) Less than 1000 ppm 1000 - 1500 ppm 1000 - 1500 ppm
LSI Index +0.5 to -0.5 +0.5 to -0.5 +0.5 to -0.5
Iron Fouling
(Biological Growth)
Iron, FE2+ (Ferrous)
Bacterial Iron Potential < 0.2 ppm < 0.2 ppm < 0.2 ppm
Iron Oxide Less than 1 ppm, above this
level deposition will occur
Less than 1 ppm, above this
level deposition will occur
Less than 1 ppm, above this
level deposition will occur
Erosion
Suspended Solids Less than 10 ppm and filtered
for max. of 600 micron size
Less than 10 ppm and filtered
for max. of 600 micron size
Less than 10 ppm and filtered
for max. of 600 micron size
Threshold Velocity
(Fresh Water) < 1.8 m/sec < 1.8 m/sec < 1.8 m/sec
NOTES: Grains = ppm divided by 17
mg/L is equivalent to ppm
2/22/12
Water Quality Guidelines

7
VERSATEC ULTRA NSKW INSTALLATION MANUAL
The proper water flow must be delivered to each unit
whenever the unit heats or cools. To assure proper flow,
the use of pressure/temperature ports is recommended
to determine the flow rate. These ports should be located
adjacent to the supply and return connections on the unit.
The proper flow rate cannot be accurately set without
measuring the water pressure drop through the refrigerant-
to-water heat exchanger (See Pressure Drop Table for water
flow and pressure drop information). Normally about 0.054
L/s flow rate per kw of cooling capacity (0.040 L/s per kw
minimum) is needed. Both source as well as load fluid piping
must be at least as large as the unit connections on the heat
pump (larger on long runs).
Never use flexible hoses of a smaller inside diameter than
that of the water connection on the unit and limit hose length
to 3.05m per connection. Check carefully for water leaks.
CAUTION: Water piping exposed to outside
temperature may be subject to freezing.
General
Each unit is equipped with captive FPT water connections
to eliminate ‘egg-shaping’ from use of a backup wrench.
For making the water connections to the unit, a Teflon tape
thread sealant is recommended to minimize internal fouling
of the piping. Do not over tighten connections. All supply and
return water piping should be insulated to prevent excess
condensation from forming on the water lines.
NOTES: 1) WaterFurnace recommends a male national pipe
thread (NPT) to British standard pipe fitting (BSPF) to
adapt to NSKW water connections. 2) Units are factory run-
tested using propylene glycol. Prior to connecting piping
to unit, thoroughly flush heat exchangers.
The piping installation should provide service personnel with
the ability to measure water temperatures and pressures.
The water lines should be routed so as not to interfere with
access to the unit. The use of a short length of high pressure
hose with a swivel type fitting may simplify the connections
and prevent vibration. Optional stainless steel hose kits are
available as an accessory item.
Before final connection to the unit, the supply and return
hose kits must be connected, and the system flushed
to remove dirt, piping chips and other foreign material.
Normally, a combination balancing and close-off (ball) valve
is installed at the return, and a rated gate or ball valve is
installed at the supply. The return valve can be adjusted to
obtain the proper water flow. The valves allow the unit to be
removed for servicing.
Field Connected Water Piping
Line Voltage
Disconnect
Load Liquid
Connections
Water Out
Water In
Rubber Bladder
Expansion Tank
Solenoid
Valve
Flow Regulator Valve
Shut-off Valve
(to isolate solenoid
valve while acid
flushing)
Boiler Drains for
HX Flushing
Shut-off
Valve
Vibration Absorbing
Mesh or Air Pad
P/T Plugs
NOTE: Valves and boiler drains must be installed
so the heat exchanger can be acid flushed.
Typical Open Loop Installation

8
VERSATEC ULTRA NSKW INSTALLATION MANUAL
Open Loop Well Water Systems
Always maintain water pressure in the heat exchanger by
placing water control valves at the outlet of the unit. Use
a closed bladder type expansion tank to minimize mineral
deposits. Ensure proper water flow through the unit by
checking pressure drop across the heat exchanger and
comparing it to the figures in the pressure drop table.
Normally, about 0.038 L/s per kW flow rate of cooling
capacity is needed in open loop systems, 0.029 L/s per kW
minimum if entering source temperature is above 10°C.
Some water control valves draw their power directly from
the unit’s 24V transformer and can overload and possibly
burn out the transformer. Check total VA draw of the water
valve(s) and ensure it is under 40 VA.
Discharge water from a heat pump can be disposed of in
various ways depending on local building codes (i.e. recharge
well, storm sewer, drain field, adjacent stream or pond,
etc.). Most local codes restrict the use of sanitary sewer for
disposal. Consult your local building and zoning departments
to ensure compliance in your area. Figure 9b: Open Loop Solenoid Valve Connection Option
Typical slow operating external 24V water solenoid valve
(type V100FPT) wiring.
Figure 9a: Open Loop Solenoid Valve Connection Option
Typical quick operating external 24V water solenoid valve
(type PPV100 or BPV100) wiring.
NOTE: SW2-4 and SW2-5 should be “OFF” to cycle with
the compressor.
Acc Com
Acc NC
Acc NO
1
2
3
C
RP1
P2
SV
Solenoid
Valve
ABC Board
NOTE: SW2-4 should be “ON” and SW2-5 should be “OFF”
when using a slow opening (V100FPT) water valve.
C
R
Acc Com
ACC NC
Acc NO
C
W/Y
V Valve ABC Board
Field Connected Water Piping cont.

9
VERSATEC ULTRA NSKW INSTALLATION MANUAL
Field Connected Water Piping cont.
Earth Coupled Systems with Flow Center
nce piping is completed between the unit, flow center and
the earth loop, final purging and charging of the loop is
needed. A pump capable of 14 m3/hr @ 25 meters of head
is needed to achieve adequate flow velocity in the loop to
purge air and dirt particles from the loop itself. Antifreeze
solution is used in most areas to prevent freezing. Maintain
the pH in the 7.6-8.2 range for final charging.
Flush the system adequately to remove as much air as
possible. Then, pressurize the loop to a static pressure of
345-517 kPa. This is normally adequate for good system
operation. Ensure that the flow center provides adequate
flow through the unit by checking pressure drop across the
heat exchanger and by comparing it to the figures shown
in the Pressure Drop tables. Usually, 0.054 L/s per kW or
minimum 0.040 L/s per kW of cooling capacity is needed in
closed loop earth-coupled applications.
Ground Loop Design and Installation
This instruction manual does not cover the design and
installation of the ground loop system. WaterFurnace
recommends that all ground loops are designed using
GeoLinkTM Design Studio (GDS) or another commercial
software package. Installers shall follow the guidelines
detailed in Microgeneration Certification Scheme (MCS)
Installation Standard MIS 3005 for designing ground loop
collectors. Additional guidance on ground collectors is
provided by International Ground-Source Heat Pump
Association (IGSHPA).
Typical Closed Loop Earth Coupled Installation
Line Voltage
Disconnect
Load Liquid
Connections
Vibration Absorbing
Mesh or Air Pad
P/T Plugs
Unit Connector Kits
with Insulation
Earth Coupled Loop
Piping with Insulation

10
VERSATEC ULTRA NSKW INSTALLATION MANUAL
Potable Water Systems
TNSKW06 kW heat pumps can be equipped with a double-
wall vented coaxial heat exchanger capable of hot water
generation (HWG). An optional factory-installed hot water
generator coil may be provided with NSKW08-17. The
temperature of the hot water produced by the heat pump
cannot be adjusted and will vary with the inlet temperature.
WaterFurnace recommends the use of a properly sized
buffer tank equipped with supplemental electric immersion
heaters in conjunction with all NSKW models used in an
HWG application. Immersion heaters must be capable
of heating the water to 60°C at a regular time interval
to prevent the build-up of bacteria such as Legionella.
Installations must meet minimum requirements outlined in
UK Domestic Heating Compliance Guide.
CAUTION: Hot water in excess of 60°C can cause
scalding.
LOAD PUMP
HYDRONIC
LOAD
Source OUT
P/T PortsP/T Ports
Ball Valve
Dielectric
Unions
Dielectric
Unions
NOTES:
* A 207 kPa pressure relief valve (Part No: SRV30) should be used in
hydronic applications.
** Vent valve or P/T port at highest point in return line prior to ball valve.
1-1/2 in.
FPT
Expansion
Tank
Air
Vent
Pressure
Gauge
207 kPa
RELIEF VALVE
Air
Separator
FROM
HWG
TO
HWG
Back Flow Preventer /
Pressure Relief Valve
Source IN
5 Series
GEO
STORAGE
TANK
PUMP
HOT
(Piped in
series to
an electric
water heater)
COLD
DOMESTIC
Dip Tube
Ball Valve
Vent Valve/
P/T Port**
Suggested Domestic Water Heater Hookup
Versatec Ultra

11
VERSATEC ULTRA NSKW INSTALLATION MANUAL
Hot Water Generator Connections
The heat reclaiming hot water generator coil is vented double-
wall copper construction and is suitable for potable water. To
maximize the benefits of the hot water generator a minimum
50-gallon water heater is recommended. For higher demand
applications, use an 80-gallon water heater as shown below or
two 50-gallon water heaters connected in a series. A geo storage
tank should not be used in this application unless it is plumbed
in a series with an electric water heater. The geo storage tank is
equipped with a single 4500 Watt element and will not be able
to provide adequate water heating if used as a standalone water
heater. Electric water heaters are recommended. Make sure all
local electrical and plumbing codes are met for installing a hot
water generator. The Versatec Ultra NSKW is not supplied with
an internal circulator.
Potable Water Systems cont.
Alternate Hot Water Installation with
Direct Coupling to a Double Wall Unit
P/T PortsP/T Ports
Ball Valve
Dielectric
Unions
Dielectric
Unions
5 Series
NSW018 or NSW025 (Heating Only)
with Double Wall Load Coax
WaterFurnace
GEOTANK
1-1/2˝
FPT
Ball Valve
HOT COLD
LOOP FIELD
FLOW CENTER
NOTES:
1) Unions and valves must be installed so that acid flushing
of the heat exchanger is possible.
2)
Make sure there is not a check valve in the diptube of
the tank.
Versatec Ultra
06 (Heating Only)

12
VERSATEC ULTRA NSKW INSTALLATION MANUAL
Hydronic Section
General guidelines are shown below for component
selection and design/installation criteria for the piping
system. Local codes supersede any recommendations in
this manual.
Shut Off/Flow Regulation Valves
Use full port ball valves or gate valves for component
isolation. If valves are going to be used frequently, ball
valves are recommended. Globe valves are designed for flow
regulation. Always install globe valves in the correct direction
(fluid should enter through the lower body chamber).
Check valves
Swing check valves must be installed in the horizontal
position with the bonnet of the valve upright. Spring check
valves can be mounted in any position. A flow check valve
is required to prevent thermo-siphoning (or gravity flow)
when the circulator pump is off or when there are two
circulators on the same system.
Storage (Buffer) Tank
A buffer tank is required for all hydronic heating systems
using Versatec Ultra heat pumps. The tank should be sized
to provide 7.6 L of storage capacity for every 300 W of
nominal heat pump capacity.
Pressure Relief Valve
Most codes require the use of a pressure relief valve if a
closed loop heat source can be isolated by valves. Even
if local code does not require this device, WaterFurnace
recommends its installation. If the pressure relief valve in
the buffer tank is not already rated at 207 kPa maximum
pressure, one must be installed. The pressure relief valve
should be tested at start up for operation. Note that the
waste pipe must be at least the same diameter as the valve
outlet (never reduce), and valves may not be added to this
pipe. The bottom of the pipe must terminate at least 15 cm
above the floor. If the piping is connected to a drain, there
must be an air gap.
Backflow Prevention Check Valves
Most codes require backflow prevention check valves.
Note that a single check valve is not equal to a backflow
prevention check valve. Even if local code does not require
this device, WaterFurnace recommends its installation. This
is particularly important if the system will use antifreeze.
Pressure Reducing Valves or Feed Water Valves
This valve lowers the pressure from the make-up water line
to the system. Most are adjustable and directional. A “fast
fill” valve is required for initial filling of the system. Some
have screens, which must be cleaned after the initial filling.
If there is a restriction in the screen, the system could go to
0 kPa, potentially causing pumps(s) failure. A valve should
be installed on each side of the pressure reducing valve for
servicing. Both valves should have tags reading “Do not
shut this valve under normal operation – service valve only.”
Expansion Tanks
Expansion tanks are required on hydronic systems to help
absorb the pressure swings as the temperature in the
system fluctuates.
Elbows/Tees
Long radius elbows or two 45° elbows will lower pressure
drop. Standard tees have a greater restriction on the “T”
portion than tees designed with angled outlet ports.
Antifreeze
Antifreeze is required if any of the piping system is located
in areas subject to freezing.
Dielectric Unions
Dielectric unions are recommended whenever connecting
two dissimilar metals to one and other to prevent electro-
galvanic corrosion.
When using the various types of hydronic heat distribution
systems, the temperature limits of the geothermal system
must be a major consideration. In new construction, the
distribution system can easily be designed with the
temperature limits in mind. In retrofits, care must be
taken to address the operating temperature limits of the
existing distribution system. The maximum storage tank
temperature for the Versatec Ultra NSKW is 54.4°C. Typical
in floor radiant systems require much lower temperatures,
typically 37.8°-46.1°C, which is ideal for the Versatec Ultra
NSKW.

13
VERSATEC ULTRA NSKW INSTALLATION MANUAL
Hydronic Section cont.
If using a Geothermal Storage tank there will be two red
wires exiting out of the top of the tank. These red wries
extend internally down to the thermistor/tank thermostat
section of the tank. Remove the bottom tank cover to expose
the red wires as well as the yellow tank thermistor wires.
HydroZone
If using HydroZone control, connect the two red wires to
the two yellow wires using wire nuts. Next, connect the two
red wires from the top of the Geothermal Storage tank to
“TS” and “GND” on the HydroZone. The “OAT” and “GND”
terminals on the HydroZone are used for an outdoor air
sensor.
HydroStat
If using HydroStat control, connect the two red wires to the
yellow wires using wire nuts. Next, connect the two red wires
from the top of the Geothermal Storage tank to “TS” and
“GND” on the HydroStat. The “OAT” and “GND” terminals
on the HydroStat are used to connect the controller to the
ELWT (Entering Load Water Temperature) well point sensor.
This sensor is located on the load side entering water line
inside the unit.
For other field installed controllers, these two red wires
will need wired to the appropriate sensor input terminals.
Another option for connection is to connect the thermostat
on the Geothermal Storage tank directly to “R” and “Y1” on
the ABC board.
LOAD PUMP
HYDRONIC
LOAD
Source OUT
P/T PortsP/T Ports
Ball Valve
Dielectric
Unions
Dielectric
Unions
NOTES:
* A 207 kPa pressure relief valve (Part No: SRV30) should be used in
hydronic applications.
** Vent valve or P/T port at highest point in return line prior to ball valve.
1-1/2 in.
FPT
Expansion
Tank
Air
Vent
Pressure
Gauge
207 kPa
RELIEF VALVE
Air
Separator
FROM
HWG
TO
HWG
Back Flow Preventer /
Pressure Relief Valve
Source IN
5 Series
GEO
STORAGE
TANK
PUMP
HOT
(Piped in
series to
an electric
water heater)
COLD
DOMESTIC
Dip Tube
Ball Valve
Vent Valve/
P/T Port**
Adequate rate of flow (L/s) is very important to system
performance and long term reliability. Follow the guidelines
for recommended flow in the recommendations table.
Combination
Unit
Geothermal Storage Tank Thermostat and Thermistor
Thermistor Wires Connected to TS and GND on
HydroZone Controller.
Water To
Water
Versatec Ultra

14
VERSATEC ULTRA NSKW INSTALLATION MANUAL
Accessories and Options
Geo Storage Tank Dimensions
Electrical Data
3
0
°
3
0
°
To Geo 150 cm Dip Tube
Approx. 2.54 cm
T & P
VALVE
From Geo
PRIMARY ANODE
99 cm - 80 Gallon
106.7 cm - 119 Gallon
COLD INLET
132.0 cm DIP TUBE
HOT OUTLET
w/35.6 cm SECONDARY ANODE
HEIGHT Element Location
Yellow Wire attached
to Thermistor or Thermostat
for Top Exit
Lower Sensor Thermistor (12P541-01)
to be used by Water to Water Units
Optional “From Geo” Connection
DIAMETER
20.3 cm
13.3 cm
90.8 cm
Lower Thermostat
DRAIN VALVE
Model
Number
Gallon [Liter]
Capacity
Element
Wattage
(240 Volt)
Number
of
Elements
R
Value
Dimensions in cm Approx Shipping
Weight kg
Height Diameter
GEO-STORAGE-80 80 [303] 4500 1 16 160.6 61.0 92.5
GEO-STORAGE-120 119 [450] 4500 1 16 160.6 71.1 141.1
Model Rated
Voltage
Voltage
Min/Max
Compressor Load
Pump
FLA
Source
Pump
FLA
Total
Unit
FLA
Min
Circ
Amp
Max
Fuse/
HACR
MCC RLA LRA LRA*
06 220-240/50/1 198/264 17.5 11.2 60.0 24.0 1.5 4.5 17.2 20.0 30
380-420/50/3 342/462 6.5 4.2 28.0 16.8 - - 4.2 5.3 6
08 220-240/50/1 198/264 27.0 17.3 97.0 34.0 1.5 4.5 23.3 27.6 40
380-420/50/3 342/462 10.0 6.4 45.0 27.0 - - 6.4 8.0 10
12 220-240/50/1 198/264 31.5 20.2 126.0 44.0 1.5 4.5 26.2 31.2 50
380-420/50/3 342/462 12.1 7.8 51.5 31.0 - - 7.8 9.8 15
17 220-240/50/1 198/264 45.0 29.0 130.0 46.0 1.5 4.5 35.0 42.3 70
380-420/50/3 342/462 19.0 12.2 87.0 52.0 - - 12.2 15.3 25
1/15/15
Notes:
* - With optional IntelliStart, Type D MCB recommended

15
VERSATEC ULTRA NSKW INSTALLATION MANUAL
Electrical Data cont.
Load Pump Power Block
Transformer
Run Capacitor
Ground Lug
Load Pump Relay
Compressor Contactor
Circuit Breakers
Source Pump Power Block
Aurora Base Control
Board (ABC)
Optional IntelliStart
Control Box
Accessory Relay
A set of “dry” contacts has been provided to control
accessory devices, such as water solenoid valves on open
loop installations, electronic air cleaners, humidifiers, etc.
This relay contact should be used only with 24 volt signals
and not line voltage power. The relay has both normally
open and normally closed contacts and can operate with
either the fan or the compressor. Use DIP switch SW2-4
and 5 to cycle the relay with blower, compressor, or control
a slow opening water valve. The relay contacts are available
on terminals #1 and #3 for normally closed, and #2 and #3
for normally open on P2.
When powering high VA draw components, or V type open
loop water valves, R should be taken ‘pre-fuse’ from the ‘R’
quick connect on the ABC board and not the ‘post-fuse’ ‘R’
terminal on the thermostat connection. If not, blown ABC
fuses might result.
Control Box Relocation
The control box can be installed on the rear of the unit. To
relocate the control box, follow the procedures below.
1. Remove all power sources to the unit.
2. Remove the unit’s top panel.
3. Cut all plastic wire ties to the following:
a) High pressure switch (black wires)
b) Low pressure switch (blue wires)
c) Freeze sensing and Thermistors
d) Compressor wires
4. Remove the four screws from the control box.
5. Relocate the control box to opposite end of the unit.
6. Using the screws removed in step 4 above, reattach the
control box.
7. Move the RS485 Keystone Coupler to the opening on the
back side of the unit.
8. Secure all wires so they do not come in contact with
refrigerant lines.
9. Replace the top of the unit.
10.Replace both access panels.
11. Reapply power sources.

16
VERSATEC ULTRA NSKW INSTALLATION MANUAL
Wiring Schematics
Black
Blue
240V
CC
T2 T1
Compressor
C
R
S
Blue
G
L1L2 220-240/50/1
Unit Power Supply
Tan(10)
Capacitor
OAT Sensor
GeoTank Sensor
OAT OAT
Tank Tank Red (GND)
Red (TS)
HydroZone
Controller
GND
TS
OAT
GND
-
+
HZC
R
C
O/B
P
V
C1
C2
C3
C4
--
NOTE 1
Black
Red
LPR
LPR
NO
NC
COM
Black/White (3)
24 VDC
Current Transducer (CT)
Thermistor
Light emitting diode - Green
Relay coil
Capacitor w/ bleed resistor
Switch - Condensate overflow
Switch - High pressure
Switch - Low pressure
Polarized connector
Factory Low voltage wiring
Factory Line voltage wiring
Field low voltage wiring
Field line voltage wiring
Optional block
DC Voltage PCB traces
Junction
Quick connect terminal
Wire nut
Field wire lug
Ground
Fuse
CC -
CO -
K6 -
K5 -
FP -
HP -
LP -
PB1, PB2 -
RV -
SW1 -
SW1 -
SW2 -
Compressor Contactor
Condensate overflow sensor
DHW pump relay
Loop pump relay
Freeze Protection
High pressure switch
Low pressure switch
Power blocks
Reversing Valve coil
DIP package 5 position AXB
TEST MODE ABC Board
DIP package 8 position ABC Board
Legend
Relay Contacts-
N.O., N.C.
G
T
132
P
L1
Breaker
Vapor Injection Valve
VIV -
LPR - Load Pump Relay OAT - Outdoor Air Temperature
Field Installed Item
LPR
NO
NC
COM
Black/White (3)
CC-T1
NOTE 4
Geothermal Tank
Thermostat
Y1
NOTE 5
R
Aurora
Board
CC2
Factory
Fault
ALG
ALM
LS
ES
ACC c
Status
AURORA BASE
CONTROL™
RV – K1
CC2
CC – K2
CC Hi – K3
Fan – K4
Alarm – K5
Acc – K6
ACC no
ACC nc
O/B
C R
LO
G
Y1 Y2
W
DH
3A-Fuse
O/B
C R
LO
G
Y1 Y2
W
DH
LO
G
HI
CCG
CC
FG
F
R
HP
HP
LP
FP2
FP2
FP1
REV
REV
CFM
PWM
ECM PWM
Factory
Factory Fan Connection
RR
CC
C
C
R
(-)
(+)
RS 485
EH2
C
EH1
C
CO
(+)
(-)
R
C
RS485 Exp Factory
Com1
Com2
Config
G
G
G
YR
SW1 Test
FP1 – 15oF/30oF
JW2 - Alarm
P11
P5
P2 P1
P8
P7
P9
P6
P3
SW2
P13
P4 FP2 – 15oF/30oF
RV – B/O
ACC – Dip 4
ACC – Dip 5
CC – Dual/Single
L – Pulse/Continuous
Reheat/Normal
Factory Use
Field ConnectionsField Connections
C
LP
FP1
F
CC
G
Y1
1
2
3
4
5
6
7
8
Off On
N/A
RS485 NET
EH1
LED1 LED2
LED3
LED4
LED5
Aurora Water-Water – 220-240/50/1

17
VERSATEC ULTRA NSKW INSTALLATION MANUAL
Wiring Schematics cont.
Transformer
24V
CC
HP
Black
Black
Blue
Blue
LP
T
Yellow
Yellow
FP1
Black(15)
Violet(14)
Green(11)
Black/White
Yellow
AID Tool
DESCRIPTION SW2-4 SW2-5
Cycle with Blower ON ON
Cycle with Compressor OFF OFF
Water Valve Slow Openi ng ON OFF
Cycle with Comm. T-stat Hum Cmd OFF ON
ABC SW2 Accessory Relay
Aurora LED Flash Codes
Status LED (LED3, Green)
Status LED (LED1, Green)
Configuration LED (LED2, Yellow)
Fault LED (LED3, Red)
Random Start Delay (Alternating Colors)
Fast Flash
Fast Flash
Fast Flash
1 second on and 1 second off
100 milliseconds on and 100 milliseconds off
100 milliseconds on and 400 milliseconds off with a 2 second pause before repeating
Slow Flash
Fast Flash
Flash Code
Normal Mode
Control is Non-Functional
Test Mode
Lockout Active
Dehumidification Mode
Future Use
Future Use
Load Shed
ESD
OFF
ON
Slow Flash
Fast Flash
Flash Code 2
Flash Code 3
Flash Code 6
Flash Code 4
Flash Code 5
Future Use Flash Code 7
Configuration LED (LED2, Yellow)
No Software Overide OFF
DIP Switch Overide Slow Flash
Fault LED (LED1, Red)
Normal Mode
Input Fault Lockout
High Pressure Lockout
Low Pressure Lockout
Future Use
Freeze Detection – FP1
Reserved
Condensate Overflow Lockout
Over/Under Voltage Shutdown
Future Use
Future Use
FP1 and FP2 Sensor Error
Flash Code 1
OFF
Flash Code 2
Flash Code 3
Flash Code 4
Flash Code 5
Flash Code 8
Flash Code 6
Flash Code 7
Flash Code 9
Flash Code 10
Flash Code 11
CFM
P13
P4
SW1
P5
JW2
P9
LO
O/B
Y2
W
DH
P8 P7
RS485 NET RS485 NET
P6
RS485 EXP
P3
SW2
On
Future Use
L Output Type
CC – Dual/Single
Acc – Dip 5
Acc – Dip 4
RV – B/O
FP2 – 15°F/30°F
FP1 – 15°F/30°F
Com1
LED5
Com2
LED5
Test Mode
F1-3A
P1
C
PWM
1
2
3
4
5
6
7
8
ALM
ALG
ACC COM
ACC NO
ACC NC
R
C
G
Y1
EH2CEH1
C
CO
CR-+C R-+
Off
Fault
LED1
R
Status
LED3
Config
LED2
CC2 CC FCR F FG CC CCGCC2
HI CC2 LO CC2 GREVREV FP1 FP1 FP2 FP2 LPS LPS HPSHPS
Aurora Base Control
(ABC)
K1-RV Relay
K2-CC Relay
K3-CC2 Relay
K4-Fan Relay
K5-Alarm
Relay
K6-Acc
Relay
F
R
C
CCGY1
C
R
ES
LS
P2
EH1
Y
GG
G
Notes
1 – HydroZone controller is an optional field installed accessory.
Blue
Blue
Not Used
Orange
Orange
T
Yellow
Yellow
FP2
RV
RV
NOTE 2
2 – Reversing Valve wires not installed on heating only option
Event Normal Mode Test Mode
Random Start Delay
Compressor On Delay
Compressor Minimum On Time
Compressor Short Cycle Delay
Fault Recognition Delay – High Pressure
Start-Up Bypass – Low Pressure
Fault Recognition Delay – Low Pressure
Start-Up Bypass – Low Water Coil Limit
Fault Recognition Delay – Low Water Coil Limit
Fault Recognition Delay – Condensate Overflow
HydroZone Call Recognition Time
Less than 1 second
5 to 80 seconds 1 second
5 seconds < 1 second
Less than 1 second
2 minutes 5 seconds
4 minutes 15 seconds
2 minutes
2 minutes
30 seconds
30 seconds 30 seconds
30 seconds
30 seconds
30 seconds
30 seconds
30 seconds
2 seconds 2 seconds
Aurora Timing Events
Water Valve Slow Open Delay 90 seconds 90 seconds
NOTE 3
3 – FP2 is replaced with a resistor on heating only option
4 – Move black/white(3) wire when HydroZone or HydroStat is not used for pump control to
LPR-NC and CC-T1
5 – When Geothermal Storage Tank is wired directly to the Aurora Board
Red
220V
6 – Switch blue and red wire for 220V operation.
NOTE 6
T2 T1
Compressor
C
R
S
Blue
Tan(6)
Cap
Run Winding
Active
Start
Common
IntelliStart
Red
Pink
Black
Blue
CC
T2 T1
L1L2 Softstart Option
Black
7 – HydroStat communicating controller is an optional field installed accessory.
Geo-Tank Sensor
ELWT: Entering Load Water Temperature Sensor
ELWT
ELWT
Geo-Tank
Geo-Tank Red (GND)
Red (TS)
Yellow (OAT)
Yellow (GND)
HydroStat
Controller
GND
TS
OAT
GND
-
+
HSC
W
R
C
P
NOTE 7
LPR 24 VDC
Aurora Water-Water – 220-240/50/1

18
VERSATEC ULTRA NSKW INSTALLATION MANUAL
Wiring Schematics - Commercial
Aurora Water-Water - 380-420/50/3
Black
Blue
420V
OAT Sensor
GeoTank Sensor
OAT OAT
Tank Tank Red (GND)
Red (TS)
HydroZone
Controller
GND
TS
OAT
GND
-
+
HZC
R
C
O/B
P
V
C1
C2
C3
C4
--
NOTE 1
LPR
LPR
NO
NC
COM
24 VDC
Current Transducer (CT)
Thermistor
Light emitting diode - Green
Relay coil
Capacitor w/ bleed resistor
Switch - Condensate overflow
Switch - High pressure
Switch - Low pressure
Polarized connector
Factory Low voltage wiring
Factory Line voltage wiring
Field low voltage wiring
Field line voltage wiring
Optional block
DC Voltage PCB traces
Junction
Quick connect terminal
Wire nut
Field wire lug
Ground
Fuse
CC -
CO -
K6 -
K5 -
FP -
HP -
LP -
PB1, PB2 -
RV -
SW1 -
SW1 -
SW2 -
Compressor Contactor
Condensate overflow sensor
DHW pump relay
Loop pump relay
Freeze Protection
High pressure switch
Low pressure switch
Power blocks
Reversing Valve coil
DIP package 5 position AXB
TEST MODE ABC Board
DIP package 8 position ABC Board
Legend
Relay Contacts-
N.O., N.C.
G
T
132
P
L1
Breaker
Vapor Injection Valve
VIV -
LPR - Load Pump Relay OAT - Outdoor Air Temperature
Field Installed Item
LPR
NO
NC
COM
Black/White (3)
CC-T1
NOTE 4
Geothermal Tank
Thermostat
Y1
NOTE 5
R
Aurora
Board
Compressor
G
CC
T1
L1
T2
L2
T3
L3
T1
T2
T3
Blue Black
Unit
Power Supply
Red
380-420/50/3
Black/White (3)
CC2
Factory
Fault
ALG
ALM
LS
ES
ACC c
Status
AURORA BASE
CONTROL™
RV – K1
CC2
CC – K2
CC Hi – K3
Fan – K4
Alarm – K5
Acc – K6
ACC no
ACC nc
O/B
C R
LO
G
Y1 Y2
W
DH
3A-Fuse
O/B
C R
LO
G
Y1 Y2
W
DH
LO
G
HI
CCG
CC
FG
F
R
HP
HP
LP
FP2
FP2
FP1
REV
REV
CFM
PWM
ECM PWM
Factory
Factory Fan Connection
RR
CC
C
C
R
(-)
(+)
RS 485
EH2
C
EH1
C
CO
(+)
(-)
R
C
RS485 Exp Factory
Com1
Com2
Config
G
G
G
YR
SW1 Test
FP1 – 15oF/30oF
JW2 - Alarm
P11
P5
P2 P1
P8
P7
P9
P6
P3
SW2
P13
P4 FP2 – 15oF/30oF
RV – B/O
ACC – Dip 4
ACC – Dip 5
CC – Dual/Single
L – Pulse/Continuous
Reheat/Normal
Factory Use
Field ConnectionsField Connections
C
LP
FP1
F
CC
G
Y1
1
2
3
4
5
6
7
8
Off On
N/A
RS485 NET
EH1
LED1 LED2
LED3
LED4
LED5

19
VERSATEC ULTRA NSKW INSTALLATION MANUAL
Wiring Schematics - Commercial cont.
Aurora Water-Water - 380-420/50/3
Transformer
24V
CC
HP
Black
Black
Blue
Blue
LP
T
Yellow
Yellow
FP1
Black(15)
Violet(14)
Green(11)
Black/White
Yellow
AID Tool
DESCRIPTION SW2-4 SW2-5
Cycle with Blower ON ON
Cycle with Compressor OFF OFF
Water Valve Slow Opening ON OFF
Cycle with Comm. T-stat Hum Cmd OFF ON
ABC SW2 Accessory Relay
Aurora LED Flash Codes
Status LED (LED3, Green)
Status LED (LED1, Green)
Configuration LED (LED2, Yellow)
Fault LED (LED3, Red)
Random Start Delay (Alternating Colors)
Fast Flash
Fast Flash
Fast Flash
1 second on and 1 second off
100 milliseconds on and 100 milliseconds off
100 milliseconds on and 400 milliseconds off with a 2 second pause before repeating
Slow Flash
Fast Flash
Flash Code
Normal Mode
Control is Non-Functional
Test Mode
Lockout Active
Dehumidification Mode
Future Use
Future Use
Load Shed
ESD
OFF
ON
Slow Flash
Fast Flash
Flash Code 2
Flash Code 3
Flash Code 6
Flash Code 4
Flash Code 5
Future Use Flash Code 7
Configuration LED (LED2, Yellow)
No Software Overide OFF
DIP Switch Overide Slow Flash
Fault LED (LED1, Red)
Normal Mode
Input Fault Lockout
High Pressure Lockout
Low Pressure Lockout
Future Use
Freeze Detection – FP1
Reserved
Condensate Overflow Lockout
Over/Under Voltage Shutdown
Future Use
Future Use
FP1 and FP2 Sensor Error
Flash Code 1
OFF
Flash Code 2
Flash Code 3
Flash Code 4
Flash Code 5
Flash Code 8
Flash Code 6
Flash Code 7
Flash Code 9
Flash Code 10
Flash Code 11
CFM
P13
P4
SW1
P5
JW2
P9
LO
O/B
Y2
W
DH
P8 P7
RS485 NET RS485 NET
P6
RS485 EXP
P3
SW2
On
Future Use
L Output Type
CC – Dual/Single
Acc – Dip 5
Acc – Dip 4
RV – B/O
FP2 – 15°F/30°F
FP1 – 15°F/30°F
Com1
LED5
Com2
LED5
Test Mode
F1-3A
P1
C
PWM
1
2
3
4
5
6
7
8
ALM
ALG
ACC COM
ACC NO
ACC NC
R
C
G
Y1
EH2CEH1
C
CO
CR-+C R-+
Off
Fault
LED1
R
Status
LED3
Config
LED2
CC2 CC FCR F FG CC CCGCC2
HI CC2 LO CC2 GREVREV FP1 FP1 FP2 FP2 LPS LPS HPSHPS
Aurora Base Control
(ABC)
K1-RV Relay
K2-CC Relay
K3-CC2 Relay
K4-Fan Relay
K5-Alarm
Relay
K6-Acc
Relay
F
R
C
CCGY1
C
R
ES
LS
P2
EH1
Y
GG
G
Blue
Blue
Not Used
Orange
Orange
T
Yellow
Yellow
FP2
RV
RV
NOTE 2 NOTE 3
Event Normal Mode Test Mode
Random Start Delay
Compressor On Delay
Compressor Minimum On Time
Compressor Short Cycle Delay
Fault Recognition Delay – High Pressure
Start-Up Bypass – Low Pressure
Fault Recognition Delay – Low Pressure
Start-Up Bypass – Low Water Coil Limit
Fault Recognition Delay – Low Water Coil Limit
Fault Recognition Delay – Condensate Overflow
HydroZone Call Recognition Time
Less than 1 second
5 to 80 seconds 1 second
5 seconds < 1 second
Less than 1 second
2 minutes 5 seconds
4 minutes 15 seconds
2 minutes
2 minutes
30 seconds
30 seconds 30 seconds
30 seconds
30 seconds
30 seconds
30 seconds
30 seconds
2 seconds 2 seconds
Aurora Timing Events
Water Valve Slow Open Delay 90 seconds 90 seconds
Red
380V
NOTE 6
Softstart Option
L2L3
CCT2T3
L1
T1
Red
3 Phase
IntelliStart
L2 (IN)
L2 (OUT)
L1 (IN)
L1 (OUT)
L3
Black
Black
Black
Blue
Yellow
T1
T2
T3
Geo-Tank Sensor
ELWT: Entering Load Water Temperature Sensor
ELWT
ELWT
Geo-Tank Geo-Tank Red (GND)
Red (TS)
Yellow (OAT)
Yellow (GND)
HydroStat
Controller
GND
TS
OAT
GND
-
+
HSC
W
R
C
P
NOTE 7
LPR 24 VDC
Notes
1 – HydroZone controller is an optional field installed accessory.
2 – Reversing Valve wires not installed on heating only option
3 – FP2 is replaced with a resistor on heating only option
4 – Move black/white(3) wire when HydroZone or HydroStat is not used for pump control to LPR-
NC and CC-T1
5 – When Geothermal Storage Tank is wired directly to the Aurora Board
6 – Switch blue and red wires for 380V operation
7 – HydroStat communicating controller is an optional field installed accessory.

20
VERSATEC ULTRA NSKW INSTALLATION MANUAL
External Control
An external controller is necessary for operation. For water storage tank set point control the HydroStat HZC, and HZ0
may be used. A field supplied aquastat may also be used as the external control to the heat pump. If zoning is required, the
Hydrologic Zone Panels and Control system can provide up to eight zones of closed loop hydronic heating and cooling.
HydroStat features:
• Communicating Controller
• Pump Sampling
• 6.4 cm x 6.4cm LCD display and five push buttons serve as the human interface
• Controls and regulates water tank temperature
• Fahrenheit or Celsius
• Single Stage
HydroZone HZC features:
• 6.4 cm x 6.4cm LCD display and five push buttons serve as the human interface
• Controls and regulates water tank temperature
• Fahrenheit or Celsius
• Outdoor reset
• Warm weather shutdown
• Single Stage
HydroZone HZO features:
• HZC mounted on 19.0 cm x 19.0 cm x 8.3 cm electrical box
• HydroZone relay board
• 6.4 cm x 6.4cm LCD display and five push buttons serve as the human interface
• Controls and regulates water tank temperature
• Fahrenheit or Celsius
• Outdoor reset
• Warm weather shutdown
• Staging (up to 4 stages)
• Lead/Lag (when staging)
HydroLogic features:
• Operates radiant floor heating
• Operates hydronic fan coil heating and cooling
• 4 zones expandable to 8 zones
• Communicating 2 wire controls
• Controls 2 stages of compressors with rotation
• Controls backup heat source
• Intelligent heat/cool switchover
• Fahrenheit or Celsius
• Outdoor reset
• Indoor temperature feedback
• Warm weather shutdown