Geo Excel RZ CS Series User manual

Installation, Operation and Maintenance Manual
RZ CS Series Heat pump
8 733 922 031 (2014/03)
RZ024 | RZ036 | RZ048 | RZO60 | RZ070

2| RZ CS Series Heat Pump
RZ CS Series Heat Pump8 733 922 031 (2014/03) Subject to change without prior notice
CONTENTS
Model Nomenclature.......................................................... 3
Key to Symbols.................................................................. 3
Safety Warnings................................................................ 3
Standard RZ CS package .................................................... 4
GENERAL DESCRIPTION .................................................... 4
MOVING AND STORAGE..................................................... 4
INITIAL INSPECTION .......................................................... 4
LOCATION......................................................................... 4
Condensing Section ..................................................... 4
Air Handler ................................................................. 5
PIPING.............................................................................. 5
ELECTRICAL...................................................................... 6
Safety Devices and the UPM Controller ........................... 6
OPTIONS......................................................................... 10
Heat Recovery Package (HRP) ..................................... 10
DPS Water Flow Proving ............................................. 10
Pump Relay............................................................... 10
Comfort Alert Module ................................................. 10
HEAT RECOVERY PACKAGE ............................................. 11
Water Tank Preparation .............................................. 11
HR Water Piping ........................................................ 11
Water Tank Refill........................................................ 12
Initial Start-Up........................................................... 12
SEQUENCE OF OPERATION .............................................. 13
Cooling Mode ............................................................ 13
Heating Mode............................................................ 13
APPLICATION CONSIDERATIONS...................................... 15
Well Water Systems ................................................... 15
Cooling Tower/Boiler Systems ..................................... 16
Geothermal Systems .................................................. 18
SYSTEM CHECKOUT ........................................................ 19
UNIT START-UP ............................................................... 19
MAINTENANCE................................................................ 20
UNIT CHECK-OUT SHEET .................................................. 21
TROUBLESHOOTING ........................................................ 22
Unit Lockouts............................................................ 25
OPERATING TEMPERATURES AND PRESSURES................. 26
WATER SIDE PRESSURE DROP TABLE............................... 31
WIRING DIAGRAMS ......................................................... 32
DIMENSIONAL DRAWINGS ............................................... 33
Notes ..............................................................................33

Model Nomenclature | 3RZ CS Series Heat
8 733 922 031 (2014/03)Revised 03-14
MODEL NOMENCLATURE
KEY TO SYMBOLS
Warnings
The following keywords are defined and can be
used in this document:
•NOTE indicates a situation that could result in
damage to property or equipment.
•CAUTION indicates a situation that could
result in minor to medium injury.
•WARNING indicates a situation that could
result in sever injury or death.
•DANGER indicates a situation that will result in
severe injury or death.
Important Information
SAFETY WARNINGS
RZ 024 - 1 CS C - F
SERIES WATER CONNECTIONS
RZ F - Front
SIZE COAX OPTIONS
024 C - Copper
036 N - Cupro-Nickel
048
060
CABINET CONFIGURATION
070 CS - Condensing Section
VOLTAGE DESIGNATIONS
1
- 208/1/60 & 230/1/60
Revision Level A
Warnings in this document are identified by
a warning triangle printed against a grey
background. Keywords at the start of the
warning indicate the type and seriousness
of the ensuing risk if measures to prevent
the risk are not taken.
This symbol indicates important information
where there is no risk to property or people.
Figure 1: CS/AH Pairings
UNIT MODEL Paired Air Handler
Unit 1 Unit 2
RZ024-1CSC RZ024-1AVX RZ024-1AHX
RZ036-1CSC RZ036-1AVX RZ036-1AHX
RZ048-1CSC RZ048-1AVX RZ048-1AHX
RZ060-1CSC RZ060-1AVX RZ060-1AHX
RZ070-1CSC RZ070-1AVX RZ070-1AHX
LEGEND:
AVX Box style Vertical Air Handler
AHX Box style Horizontal Air Handler
Installation and servicing of this equipment
can be hazardous due to system pressure
and electrical components. Only trained
and qualified personnel should install,
repair, or service the equipment.
Before performing service or maintenance
operations on the system, turn off main
power to the unit. Electrical shock could
cause personal injury or death.
All refrigerant discharged from this unit
must be recovered WITHOUT EXCEPTION.
Technicians must follow industry accepted
guidelines and all local, state, and federal
statutes for the recovery and disposal of
refrigerants. If a compressor is removed
from this unit, refrigerant circuit oil will
remain in the compressor. To avoid leakage
of compressor oil, refrigerant lines of the
compressor must be sealed after it is
removed.
To avoid equipment damage, DO NOT use
these units as a source of heating or cooling
during the construction process. Doing so
may affect the unit’s warranty. The
mechanical components and filters will
quickly become clogged with construction
dirt and debris, which may cause system
damage.

4| Standard RZ CS package RZ CS Series Heat Pump
RZ CS Series Heat Pump8 733 922 031 (2014/03) Subject to change without prior notice
STANDARD RZ CS PACKAGE
Figure # 2
[1] RZ Series Water-to-Air Heat Pump: Condensing
Section
[2] Installation and Operation Manual
GENERAL DESCRIPTION
RZ Series Water-to-Air Heat Pumps provide the
best combination of performance and efficiency
available. All units are performance certified to
American Heating and Refrigeration Institute
(AHRI) ISO Standard 13256-1. All RZ Water-to-Air
Heat Pumps conform to UL1995 standard and are
certified to CAN/CSA C22.1 No 236 by Intertek-
ETL. The Water-to-Air Heat Pumps are designed to
operate with entering fluid temperature between
30°F to 90°F in the heating mode and between
40°F to 120°F in the cooling mode.
Several factory installed options are available:
Heat Recovery Package, Smart Start Assist, DPS
Water Flow Proving Switch, Auxiliary Pump Relay,
and Comfort Alert Module.
Safety devices are built into each unit to provide
the maximum system protection possible when
properly installed and maintained.
MOVING AND STORAGE
If the equipment is not needed for immediate
installation upon its arrival at the job site, it should
be left in its shipping carton and stored in a clean,
dry area. Units must only be stored or moved in the
normal upright position as indicated by the “UP”
arrows on each carton at all times.
INITIAL INSPECTION
Be certain to inspect all cartons or crates on each
unit as received at the job site before signing the
freight bill. Verify that all items have been received
and that there are no visible damages; note any
shortages or damages on all copies of the freight
bill. In the event of damage or shortage, remember
that the purchaser is responsible for filing the
necessary claims with the carrier. Concealed
damages not discovered until after removing the
units from the packaging must be reported to the
carrier within 24 hours of receipt.
LOCATION
To maximize system performance, efficiency and
reliability, and to minimize installation costs, it is
always best to keep the refrigerant lines as short
as possible. Every effort should be made to locate
the air handler and the condensing section as
close as possible to each other.
Condensing Section
Locate the condensing section in an area that
provides sufficient room to make water and
electrical connections, and allows easy removal of
the access panels, for service personnel to
perform maintenance or repair.
The condensing section is designed for indoor use
primarily; however, if the condensing section must
be installed in an outdoors location where ambient
temperatures can fall below freezing, some form of
freeze protection should be employed such as a
freeze-stat and/or a pump timer/starter to prevent
possible condenser freeze-up and to optimize
overall system performance.
50°F Minimum Entering Water Temperature
(EWT) is recommended for well water
applications with sufficient water flow to prevent
freezing. Antifreeze solution is required for all
closed loop applications. Cooling Tower/Boiler
and Geothermal applications should have
sufficient antifreeze solution to protect against
extreme conditions and equipment failure.
Frozen water coils are not covered under
warranty. Other equivalent methods of
temperature control are acceptable.
1
2
For storage If unit stacking is required,
stack units as follows:
Do not stack units larger than 6 tons!

Piping | 5RZ CS Series Heat
8 733 922 031 (2014/03)Revised 03-14
Air Handler
Locate the air handler unit in an indoor area that
allows easy removal of the filter and access panels,
and has enough room for service personnel to
perform maintenance or repair. Provide sufficient
room to make electrical and duct connections. If
the unit is located in a confined space such as a
closet, provisions must be made for return air to
freely enter the space. On horizontal units, allow
adequate room below the unit for a condensate
drain trap.
Vertical units should be mounted level on a
vibration absorbing pad slightly larger than the
base to minimize vibration transmission to the
building structure. It is not necessary to anchor the
unit to the floor. (Figure #3).
Figure # 3
PIPING
Supply and return piping must be as large as the
unit connections on the heat pump (larger on long
runs).
RZ units are supplied with either a copper or
optional cupro-nickel condenser. Copper is
adequate for ground water that is not high in
mineral content.
In conditions anticipating moderate scale
formation or in brackish water a cupro-nickel heat
exchanger is recommended.
Both the supply and discharge water lines will
sweat if subjected to low water temperature.
These lines should be insulated to prevent damage
from condensation. All manual flow valves used in
the system must be ball valves. Globe and gate
valves must not be used due to high pressure drop
and poor throttling characteristics.
Always check carefully for water leaks and repair
appropriately. Units are equipped with female pipe
thread fittings. Consult Unit Dimensional
Drawings. (Pg#91 through Pg#95)
Flexible hoses should be used between the unit
and the rigid system to avoid possible vibration.
Ball valves should be installed in the supply and
return lines for unit isolation and unit water flow
balancing.
The air handler units are not approved for
outdoor installation; therefore, they must be
installed inside the structure being conditioned.
Do not locate in areas that are subject to
freezing.
Reference the Factory Manual for your AH or
the Air Handler section of this manual for
detailed installation and operation.
Never use flexible hoses of a smaller inside
diameter than that of the fluid connections
on the unit.
Proper testing is recommended to assure the
well water quality is suitable for use with water
source equipment. When in doubt, use cupro-
nickel.
VIBRATION
PAD FULL
Never exceed the recommended water flow
rates as serious damage or erosion of the
water-to-refrigerant heat exchanger could
occur.
Teflon tape sealer should be used when
connecting water piping connections to the units
to insure against leaks and possible heat
exchanger fouling.
Do not overtighten the connections.

6| Electrical RZ CS Series Heat Pump
RZ CS Series Heat Pump8 733 922 031 (2014/03) Subject to change without prior notice
ELECTRICAL
Refer to electrical component box layout.
(Figure #4)
Properly sized fuses or HACR circuit breakers must
be installed for branch circuit protection. See unit
nameplate for maximum fuse or breaker size.
The unit is provided with a concentric knock-out
for attaching common trade sizes of conduit, route
power supply wiring through this opening. Always
connect the ground lead to the grounding lug
provided in the control box and power leads to the
line side of compressor contactor as indicated on
the wiring diagram (Figures on Pg#30).
Figure # 4
[1] Comfort Alert Module (Option)
[2] Compressor contactor
[3] Capacitor
[4] Auxiliary Relay (DP/DT)
[5] Terminal block (Option)
[6] Unit Protection Module (UPM)
Safety Devices and the UPM Controller
Figure # 5
[1] Board Power Indicator
[2] UPM Status LED Indicator
[3] Water Coil Freeze Protection Temperature
Selection [R30]
[4] UPM Board Settings
[5] Water Coil Freeze Connection
[6] 24VAC Power Input
[7] Compressor Contact Output
[8] High Pressure Switch Connection
[9] Call for Compressor Y1
[10] Low Pressure Switch Connection
[11] 24VAC Power Common
[12] Dry Contact
[13] UPM Ground Standoff
Field wiring must comply with local and
national electric codes.
Power to the unit must be within the
operating voltage range indicated on
the unit nameplate or on the
performance data sheet.
Operation of unit on improper line
voltage or with excessive phase
imbalance will be hazardous to the unit,
constitutes abuse and may void the
warranty.
1
2
3
4
5
6
If the unit is being connected to a thermostat
with a malfunction light, this connection is made
at the unit malfunction output or relay. Refer to
Figure #5.
If the thermostat is provided with a malfunction
light powered off of the common (C) side of the
transformer, a jumper between “R” and “COM”
terminal of “ALR” contacts must be made.
1
2
3
4
5
6
7
9
10
11 12
13
8

Electrical | 7RZ CS Series Heat
8 733 922 031 (2014/03)Revised 03-14
Each unit is factory provided with a Unit Protection
Module (UPM) that controls the compressor
operation and monitors the safety controls that
protect the unit.
Safety controls include the following:
• High pressure switch located in the refrigerant
discharge line and wired across the HPC
terminals on the UPM.
• Low pressure switch located in the unit
refrigerant suction line and wired across
terminals LPC1 and LPC2 on the UPM.
• Water side freeze protection sensor, mounted
close to condensing water coil, monitors
refrigerant temperature between condensing
water coil and thermal expansion valve. If
temperature drops below or remains at freeze
limit trip for 30 seconds, the controller will
shut down the compressor and enter into a
soft lockout condition. The default freeze limit
trip is 30°F, however this can be changed to
15°F by cutting the R30 or Freeze1 resistor
located on top of DIP switch SW1 (Refer to
Figure #5, item [3] for resistor location), Refer
to Figure #6 for sensor location.
Figure # 6
The UPM Board includes the following features:
• ANTI-SHORT CYCLE TIMER: 5 minute delay on
break timer to prevent compressor short cycling.
• RANDOM START: Each controller has an unique
random start delay ranging from 270 to 300 seconds
on initial power up to reduce the chance of multiple
unit simultaneously starting at the same time after
power up or after a power interruption, thus
avoiding creating large electrical spike.
• LOW PRESSURE BYPASS TIMER: If the
compressor is running and the low pressure switch
opens, the controller will keep the compressor ON
for 120 seconds. After 2 minutes if the low pressure
switch remains open, the controllers will shut down
the compressor and enter a soft lockout. The
compressor will not be energized until the low
pressure switch closes and the anti-short cycle time
delay expires. If the low pressure switch opens 2-4
times in 1 hour, the unit will enter a hard lockout. In
order to exit hard lockout power to the unit would
need to be reset.
• BROWNOUT/SURGE/POWER INTERRUPTION
PROTECTION: The brownout protection in the
UPM board will shut does the compressor if the
incoming power falls below 18 VAC. The compressor
will remain OFF until the voltage is above 18 VAC
and ANTI-SHORT CYCLE TIMER (300 seconds) times
out. The unit will not go into a hard lockout.
If the thermostat is provided with a malfunction
light powered off of the hot (R) side of the
transformer, then the thermostat malfunction
light connection should be connected directly to
the (ALR) contact on the unit’s UPM board.
UPM Board Dry Contacts are Normally Open
(NO)
If unit is employing a fresh water system (no
anti-freeze protection), it is extremely
important to have the Freeze1 R30 resistor
set to 30°F in order to shut down the unit at
the appropriate leaving water temperature
and protect your heat pump from freezing if
a freeze sensor is included.
UPM Board Factory Default Settings
TEMP 30°F
LOCKOUT 2
RESET Y
ALARM PULSE
TEST NO
UPM DIP SWITCH DEFAULT POSITION
lockout 42
reset RY
alarm Cont pulse
test yes no

8| Electrical RZ CS Series Heat Pump
RZ CS Series Heat Pump8 733 922 031 (2014/03) Subject to change without prior notice
• MALFUNCTION OUTPUT: Alarm output is
Normally Open (NO) dry contact. If pulse is
selected the alarm output will be pulsed. The
fault output will depend on the dip switch
setting for "ALARM". If it is set to "CONST", a
constant signal will be produced to indicate a
fault has occurred and the unit requires
inspection to determine the type of fault. If it is
set to "PULSE", a pulse signal is produced and
a fault code is detected by a remote device
indicating the fault. See L.E.D Fault Indication
below for blink code explanation. The remote
device must have a malfunction detection
capability when the UPM board is set to
"PULSE".
• DISPLAY OUTPUT: The Display output is a pulse
output connected to the Unit Diagnostic Display
(UDD) and it pulses 24VAC when the unit is in an
lockout alarm condition.
• TEST DIP SWITCH: A test dip switch is provided to
reduce all time delays settings to 10 seconds during
troubleshooting or verification of unit operation.
• FREEZE SENSOR: The default setting for the
freeze limit trip is 30°F (sensor number 1); however
this can be changed to 15°F by cutting the R30
resistor located on top of the DIP switch SW1. The
default setting for the freeze limit trip is 30°F
(sensor number 1); however this can be
changed to 15°F by cutting the R24 resistor
located on top of the DIP switch SW1. Since
freeze sensor 2 is dedicated to monitor the
evaporator coil it is recommended to leave the
factory default setting on the board. The UPM
controller will constantly monitor the
refrigerant temperature with the sensor
mounted close to the condensing water coil
between the thermal expansion valve and
water coil. If temperature drops below or
remains at the freeze limit trip for 30 seconds,
the controller will shut the compressor down
and enter into a soft lockout condition. Both
the status LED and the Alarm contact will be
active. The LED will flash (three (3) times) the
code associated with this alarm condition. If
this alarm occurs 2 times (or 4 if Dip switch is
set to 4) within an hour the UPM controller will
enter into a hard lockout condition. It will
constantly monitor the refrigerant temperature
with the sensor mounted close to the
evaporator between the thermal expansion
valve and evaporator coil as shown in Figure
#5. If temperature drops below or remains at
the freeze limit trip for 30 seconds, the
controller will shut the compressor down and
enter into a soft lockout condition. Both the
status LED and the Alarm contact will be
active. The LED will flash (six (6) times) the
code associated with this alarm condition. If
this alarm occurs 2 times (or 4 if Dip switch is
set to 4) within an hour the controller will enter
into a hard lockout condition.
• INTELLIGENT RESET: If a fault condition is
initiated, the 5 minute delay on break time period is
initiated and the unit will restart after these delays
expire. During this period the fault LED will indicate
the cause of the fault. If the fault condition still
exists or occurs 2 or 4 times (depending on 2 or 4
setting for Lockout dip switch) before 60 minutes,
the unit will go into a hard lockout and requires a
manual lockout reset. A single condensate overflow
fault will cause the unit to go into a hard lockout
immediately, and will require a manual lockout
reset.
• LOCKOUT RESET: A hard lockout can be reset
by turning the unit thermostat off and then
back on when the “RESET” dip switch is set to
“Y” or by shutting off unit power at the circuit
breaker when the “RESET” dip switch is set to
“R”.
If 24 VAC output is needed, R must be wired to
ALR-COM terminal; 24 VAC will be available o
the ALR-OUT terminal when the unit is in the
alarm condition.
Operation of unit in test mode can lead to
accelerated wear and premature failure of
components. The "TEST" switch must be set
back to "NO" after troubleshooting/
servicing.
Freeze sensor will not guard against the loss
of water. Flow switch is recommended to
prevent unit from running if water flow is
lost or reduced.
The blower motor will remain active during a
lockout condition.

Options | 9RZ CS Series Heat
8 733 922 031 (2014/03)Revised 03-14
OPTIONS
Number of factory installed options are available
on RZ Series of Heat Pumps. The following details
the purpose, function and components of each
option.
Heat Recovery Package (HRP)
The heat recovery package is a factory installed
option on RZ series of heat pumps. The HRP can be
used to heat potable water during unit operation
using waste heat from the compressor discharge
gas. In some cases the HRP can provide most or all
of the hot water requirements for a typical home.
The HRP consists of three major components:
• double wall, vented refrigerant to water heat
exchanger
•circulatingpump
•controlcircuit
The heat exchanger is rated for use with potable
water and is acceptable for use as a domestic
water heating device in most building codes.
The pump circulates water between the domestic
hot water tank and HRP heat exchanger in the Heat
Pump. The control circuit ensures that the HRP
only operates when there is available heat from the
compressor and when the water is within a safe
temperature range of below 140 deg F.
When the heat pump compressor operates, the
HRP will monitor the temperature of the discharge
gas from the compressor. Once discharge gas is
hot enough to provide useful heat to the domestic
water tank, the circulating pump will be enabled,
drawing water from the tank, through the HRP heat
exchanger and then depositing the heated water
back into the tank. If the water temperature
reaches 140 deg F, the circulating pump is
disabled to prevent over heating of the domestic
water. The HRP is provided with an on/off switch
in case the end user desires that the HRP be
inactivated (typically during the winter months
when space heating is most important).
DPS Water Flow Proving
The DPS water flow proving switch is a factory
installed option available for the RZ series. The
DPS prevents compressor operation if there is
inadequate water flow through the water to
refrigerant heat exchanger in the heat pump.
The DPS operates by monitoring the water side
pressure drop across the water to refrigerant heat
exchanger. When the pressure drop between the
water in and water out lines reaches a pre-set
value, compressor operation is enabled.
Pump Relay
The factory installed pump relay can be used to
energize a supply pump or solenoid valve when
there is a call for compressor operation. This relay
can be used to switch either high or low voltage
power.
Comfort Alert Module
The Comfort Alert diagnostics module (CADM) is a
breakthrough innovation for troubleshooting heat
pump system failures. (Figure #7)
Figure # 7
By monitoring and analyzing data from the
compressor and the thermostat demand, the
module can accurately detect the cause of
electrical and system related failures without any
sensors. A flashing LED indicator communicates
the ALERT code and guides the service technician
more quickly and accurately to the root cause of a
problem.
When an abnormal system condition occurs, the
Comfort Alert module displays the appropriate
ALERT and/or TRIP LED.
The yellow ALERT LED will flash a number of times
consecutively, pause and then repeat the process.
If heat recovery unit is installed in an area
where freezing may occur, the unit must be
drained during winter months to prevent
heat exchanger damage. Heat exchanger
ruptures that occur due to freezing will void
the heat recovery package warranty along
with the heat pump warranty.
This module does not provide safety protection!
The Comfort Alert module is a monitoring device
and cannot shut down the compressor directly.

10 | Heat Recovery Package RZ CS Series Heat Pump
RZ CS Series Heat Pump8 733 922 031 (2014/03) Subject to change without prior notice
To identify a Flash Code number, count the
number of consecutive flashes.
Every time the module powers up, the last ALERT
Flash Code that occurred prior to shut down is
displayed for one minute.Heat Recovery Package
HEAT RECOVERY PACKAGE
Water Tank Preparation
1. Turn off electrical or fuel supply to the water
heater.
2. Attach garden hose to water tank drain
connection and run other end of hose out
doors or to an open drain.
3. Close cold water inlet valve to water heater
tank.
4. Drain tank by opening drain valve on the
bottom of the tank, then open pressure relief
valve or hot water faucet.
5. Once drained the tank should be flushed with
cold water until the water leaving the drain
hose is clear and free of sediment.
6. Close all valves and remove the drain hose.
7. Install HR water piping.
HR Water Piping
All hot water piping MUST be a minimum of 3/8t
O.D. copper tube to a maximum distance of fifteen
(15) feet. For distances beyond fifteen feet but not
exceeding sixty (60) feet use 1/2” copper tube.
Separately insulate all exposed surface of both
connecting water lines with 3/8” wall closed cell
insulation. Install isolation valves on supply and
return to the heat recovery. (Figure #8)
Figure # 8
Concentric water fitting (p/n 520-105) is
recommended.
Hot
Water
Supply
Cold
Water
Supply
T/P Valve
Water Out
Retrun from HRP
Isolation Valves
Concentric Fitting
Part #520105
Tank Drain Valve
Water In
Supply to HRP
Drain Valve
(Optional)
NOTE: Diagram for illustration purposes only.
Ensure access to Heat Pump is not restricted.

Heat Recovery Package | 11RZ CS Series Heat
8 733 922 031 (2014/03)Revised 03-14
Water Tank Refill
1. Open the cold water supply to the tank.
2. Open a hot water faucet to vent air from the
system until water flows from the faucet, then
close.
3. Depress the hot water tank pressure relief
valve handle to ensure there is no air remaining
in the tank.
4. Carefully inspect all plumbing for water leaks.
Correct as required.
5. Purge all air from HR by depressing the
schrader valve on the HR Unit. Allow all air to
bleed out until water appears at the valve.
6. Before restoring the power or fuel supply to
the water heater, adjust the temperature
setting on the tank thermostat(s) to ensure
maximum utilization of the heat available from
the refrigeration system and conserve the most
energy. On tanks with both upper and lower
elements and thermostats, the lower element
should be turned down to 100° F, while the
upper element should be adjusted to 120° F.
Depending upon the specific needs of the
customer, you may need to adjust the upper
element differently. On tanks with a single
thermostat lower the thermostat setting to
120° F or the “LOW” position. After thermostat
adjustments are completed, replace access
cover and restore electrical or fuel supply to
water heater.
Initial Start-Up
1. Turn on the heat pump. The HR pump should
not run if the compressor is not running.
2. Turn HR switch to the “ON” position. The pum p
will operate if entering water temperature to
HR is below 120° F.
3. The temperature difference between the water
entering and leaving the heat recovery should
be 5° to 15° F.
4. Allow the unit to operate for 20 to 30 minutes
to ensure it is functioning properly. The pump
should shut off when the water temperature
entering the heat recovery reaches 120°F.
All piping from HRP to domestic water tank
must be copper or any metal of stronger
alloy.
Make sure all valves in heat recovery water
piping system are open. NEVER OPERATE
HR PUMP DRY.

12 | Sequence of Operation RZ CS Series Heat Pump
RZ CS Series Heat Pump8 733 922 031 (2014/03) Subject to change without prior notice
SEQUENCE OF OPERATION
Cooling Mode
Energizing the “O” terminal energizes the unit
reversing valve thus placing the unit into cooling
mode. The fan motor starts when the “G” terminal
is energized.
When the thermostat calls for first stage cooling
(Y1) the loop pump or solenoid valve if present is
energized and the first stage of compressor
capacity starts. The fan ramps up to first stage
cooling air flow in 30 seconds.
When the thermostat calls for second stage
cooling (Y2) the second stage (or full compressor
capacity) is initiated. The fan ramps up to full
cooling air flow.
Once the thermostat is satisfied, the compressor
shuts down and the fan ramps down to either fan
only mode or off over a span of 30 seconds.
Heating Mode
The first two stages of heating (Y1 & Y2) operate in
the same manner as cooling, but with the reversing
valve de-energized. On a call for auxiliary heat
(W1), the fan ramps up to auxiliary heat air flow
immediately and the electric heater package is
energized along with the compressor.
As the thermostat is satisfied, the heaters will shut
off as soon as W1 is de-energized, and the
compressors will remain on until the thermostat
stages are satisfied.
Once the thermostat is satisfied, the compressor
shuts down and the fan ramps down either fan only
mode or off over a span of 30 seconds. If
thermostat has two different output points one for
Auxiliary heat and a different one for Emergency
heat the two outputs must be terminated on W1
units equipped with one stage of Electric heat.
(Figure #9)
The fan motor will take 30 seconds to ramp up
to operating speed and will run at fan only rated
air flow as long as there is no call for compressor
or heater operation.
Some options will have a built in delay, and
hence, compressor operation is not immediate.
See ‘Options’ sections for more detail.
Note that a fault condition initiating a lockout will
de-energize the compressor irrespective of
which stage is engaged.
If the unit compressor locks out for any reason
at this time, the electric heaters will continue to
function normally.
When using a 2-cool, 3-heat thermostat both the
W1 & W2 on the Heat Pump and W2 & EM on
the thermostat must be connected together via
a jumper. (See Figure#107)

Sequence of Operation | 13RZ CS Series Heat
8 733 922 031 (2014/03)Revised 03-14
Figure # 9
UPM Sequence of Operation (SOO) Flow Chart
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
YES
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
NO
Y1=1
V
>
18VAC
HPC = 1
LPC = 1
FRZ
> TEMP
LIM
CON
> 0
INITIAL
POWER UP T
>
ASC OR
RS SEC
TIME
> 30
SEC
TIME
> 120
SEC
COUNT = 2
Start Timer
Start Timer
CC Output = On
CC Output = Off
Blink Code On Status LED
Report Alarm Fault
Hard Lockout
ALR Output = On/Pulse
Blink Code On Status LED
Soft Lockout
Record Alarm
Start Counter (If Applicable)
Start
Anti Short Cycle
Start
Random Start Up
Lockout Can Be Set To
4 Via Dip Switch
Power/Switchs/Sensor
Status Check
LEGEND:
HPC - HIGH PRESSURE CUTOUT
LPC - LOW PRESSURE CUTOUT
FRZ - FREEZE PROTECTION CONDITION
CON - CONDENSATE OVERFLOW CONDITION
CC - COMPRESSOR COIL
ASC - ANTI SHORT CYCLE
RS - RANDDOM START

14 | Application Considerations RZ CS Series Heat Pump
RZ CS Series Heat Pump8 733 922 031 (2014/03) Subject to change without prior notice
APPLICATION CONSIDERATIONS
Well Water Systems
Copper is adequate for ground water that is not
high in mineral content. Should your well driller
express concern regarding the quality of the well
water available or should any known hazards exist
in your area, we recommend proper testing to
assure the well water quality is suitable for use
with water source equipment. In conditions
anticipating moderate scale formation or in
brackish water a cupro-nickel heat exchanger is
recommended. In well water applications water
pressure must always be maintained in the heat
exchanger. This can be accomplished with either
control valve or a bladder type expansion tank.
When using a single water well to supply both
domestic water and the heat pump care must be
taken to insure that the well can provide sufficient
flow for both. In well water applications a slow
closing solenoid valve must be used to prevent
water hammer. Solenoid valves should be
connected across Y1 and C1 on the interface board
for all. Make sure that the VA draw of the valve
does not exceed the contact rating of the
thermostat. (Figure #10)
Figure # 10 Example System Set-up
[1] Flex Duct Connection
[2] Low Voltage Control Connection
[3] Vibration Pad
[4] Ball Valves
[5] Solenoid Valve Slow Closing
[6] Condensate Drain Connection
[7] Drain Valves
[8] Hose Kits (optional)
[9] Pressure Tank (optional)
[10] P/T Ports (optional)
[11] Line Voltage Connection
[12] Electric Heater Line Voltage Disconnect
[13] Unit Line Voltage Disconnect
1
2
3
4
5
6
7Typical Installation shown for
illustration purposes only.
9
8
10
11
12
13

Application Considerations | 15RZ CS Series Heat
8 733 922 031 (2014/03)Revised 03-14
Cooling Tower/Boiler Systems
The cooling tower and boiler water loop
temperature is usually maintained between 50° F
to 100 ° F to assure adequate cooling and heating
performance.
In the cooling mode, heat is rejected from the unit
into the water loop. A cooling tower provides
evaporative cooling to the loop water thus
maintaining a constant supply temperature to the
unit. When utilizing open cooling towers, chemical
water treatment is mandatory to ensure the water
is free from corrosive elements. A secondary heat
exchanger (plate frame) between the unit and the
open cooling tower may also be used.
It is imperative that all air be eliminated from the
closed loop side of the heat exchanger to insure
against fouling. In the heating mode, heat is
absorbed from the water loop. A boiler can be
utilized to maintain the loop at the desired
temperature.
Consult the specification sheets for piping sizes.
Ball valves should be installed in the supply and
return lines for unit isolation and unit water flow
balancing. Pressure/temperature ports are
recommended in both supply and return lines for
system flow balancing. Water flow can be
accurately set by measuring the water-to-
refrigerant heat exchangers water side pressure
drop. See specification sheets for water flow vs.
pressure drop information.
No unit should be connected to the supply or
return piping until the water system has been
completely cleaned and flushed to remove any dirt,
piping chips or other foreign material. Supply and
return hoses should be connected together during
this process to ensure the entire system is
properly flushed. After the cleaning and flushing
has taken place the unit may be connected to the
water loop and should have all valves wide open.
Water piping exposed to extreme low
ambient temperatures is subject to
freezing.
Teflon tape sealer should be used when
connecting to the unit to insure against leaks
and possible heat exchanger fouling.
Do not overtighten the connections. Flexible
hoses should be used between the unit and the
rigid system to avoid possible vibration

16 | Application Considerations RZ CS Series Heat Pump
RZ CS Series Heat Pump8 733 922 031 (2014/03) Subject to change without prior notice
Geothermal Systems
Closed loop and pond applications require
specialized design knowledge. No attempt at these
installations should be made unless the dealer has
received specialized training. Utilizing the Ground
Loop Pumping Package (GLP), makes the
installation easy. Anti-freeze solutions are utilized
when low evaporating conditions are expected to
occur. Refer to the GLP installation manuals for
more specific instructions. (Figure #11)
Figure # 11
[1] Line voltage disconnect (unit)
[2] Flex duct Connection
[3] Low voltage control connection
[4] Line voltage connection (unit)
[5] P/T ports
[6] Vibration pad
[7] Condensate drain connection
[8] Ground loop connection kit
[9] Ground loop pumping package
[10] Polyethylene with insulation
[11] Line voltage disconnect (electric heater)
Diagram shows typical
installation and is for
illustration purposes
only. Ensure access to
Heat Pump is not
restricted.

System Checkout | 17RZ CS Series Heat
8 733 922 031 (2014/03)Revised 03-14
SYSTEM CHECKOUT
After completing the installation, and before
energizing the unit, the following system checks
should be made:
1. Verify that the supply voltage to the heat pump
is in accordance with the nameplate ratings.
2. Make sure that all electrical connections are
tight and secure.
3. Check the electrical fusing and wiring for the
correct size.
4. Verify that the low voltage wiring between the
thermostat and the unit is correct.
5. Verify that the water piping is complete and
correct.
6. Check that the water flow is correct, and
adjust if necessary.
7. Check the blower for free rotation, and that it
is secured to the shaft.
8. Verify that vibration isolation has been
provided.
9. Unit is serviceable. Be certain that all access
panels are secured in place.
Considerations:
• Always check incoming line voltage power
supply and secondary control voltage for
adequacy. Transformer primaries are dual
tapped for 208 and 230 volts. Connect the
appropriate tap to ensure a minimum of 18
volts secondary control voltage. 24 volts is
ideal for best operation.
•Longlengththermostatand control wiring
leads may create voltage drop. Increase wire
gauge or up-size transformers may be required
to insure minimum secondary voltage supply.
• FHP recommends the following guidelines for
wiring between a thermostat and the unit: 18
GA up to 60 foot, 16 GA up to 100 ft and 14 GA
up to 140 ft.
• Do not apply additional controlled devices to
the control circuit power supply without
consulting the factory. Doing so may void
equipment warranties.
• Check with all code authorities on
requirements involving condensate disposal/
over flow protection criteria.
UNIT START-UP
1. Set the thermostat to the highest setting.
2. Set the thermostat system switch to “COOL”,
and the fan switch to the “AUTO” position. The
reversing valve solenoid should energize. The
compressor and fan should not run.
3. Reduce the thermostat setting approximately 5
degrees below the room temperature.
4. Verify the heat pump is operating in the cooling
mode.
5. Turn the thermostat system switch to the
“OFF” position. The unit should stop running
and the reversing valve should de energize.
6. Leave the unit off for approximately (5)
minutes to allow for system equalization.
7. Turn the thermostat to the lowest setting.
8. Set the thermostat switch to “HEAT”.
9. Increase the thermostat setting approximately
5 degrees above the room temperature.
10. Verify the heat pump is operating in the heating
mode.
11. Set the thermostat to maintain the desired
space temperature.
12. Check for vibrations, leaks, etc.
MAINTENANCE
1. Filter changes or cleanings are required at
regular intervals. The time period between
filter changes will depend upon type of
environment the equipment is used in. In a
single family home, that is not under
construction, changing or cleaning the filter
every 60 days is sufficient. In other
applications such as motels, where daily
vacuuming produces a large amount of lint,
filter changes may need to be as frequent as
biweekly.
Ensure cabinet and Electrical Box are
properly grounded.
Equipment should never be used during
construction due to likelihood of wall board
dust accumulation in the air coil of the
equipment which permanently affects the
performance and may shorten the life of the
equipment.

18 | Maintenance RZ CS Series Heat Pump
RZ CS Series Heat Pump8 733 922 031 (2014/03) Subject to change without prior notice
2. An annual “checkup” is recommended by a
licensed refrigeration mechanic. Recording the
performance measurements of volts, amps,
and water temperature differences (both
heating and cooling) is recommended. This
data should be compared to the information on
the unit’s data plate and the data taken at the
original startup of the equipment.
3. Lubrication of the blower motor is not
required, however may be performed on some
motors to extend motor life. Use SAE-20 non-
detergent electric motor oil.
4. The condensate drain should be checked
annually by cleaning and flushing to insure
proper drainage.
Figure 12: Refrigerant Charge, Line Sizing and Capacity Multiplier Chart
SYSTEM
MODEL
Factory
R410A
Charge
(Oz)*
Refrigerant Line O.D. Size (Based on Equivalent Line Length) Suct. Line
Riser Max.
25 FT. 35 FT. 45 FT. 50 FT. 75 FT
LIQ. SUC. LIQ. SUC. LIQ. SUC. LIQ. SUC. LIQ. SUC.
RZ024 80 3/8 3/4 3/8 3/4 3/8 3/4 3/8 3/4 3/8 7/8 3/4
RZ036 86 3/8 3/4 3/8 3/4 3/8 3/4 3/8 7/8 3/8 7/8 3/4
RZ048 93 3/8 7/8 3/8 7/8 3/8 7/8 3/8 7/8 3/8 7/8 7/8
RZ060 115 3/8 1-1/8 3/8 1-1/8 3/8 1-1/8 3/8 1-1/8 3/8 1-1/8 7/8
RZ070 127 3/8 1-1/8 3/8 1-1/8 3/8 1-1/8 3/8 1-1/8 3/8 1-1/8 7/8
CAPACITY MULTIPLIER 1.00 .995 0.990 0.990 0.980
Example 1:
Model RZ036 with 45ft of equivalent length of 3/8” O.D Liquid
Line. Total system charge= Factory charge + (45ft - 25 ft) x .60
oz/ft Total System Charge =86 oz + (20ft x .60 oz/ft) = 98 oz.
Additional 12 oz of R410A refrigerant required.
Example 2:
Model RZ060 with 10ft of equivalent length of 3/8” O.D Liquid
Line. Total system charge= Factory charge - (25ft - 10ft) x .60
oz/ft Total System Charge = 115 oz - (15ft x .60 oz/ft) = 106
oz. Removal of 9oz of R410A refrigerant required.
Note: Charge value shown for paired RZ air handler.
Figure 13: Liquid Line Charge Per Linear Foot
Liquid Line Size, O.D.
1/4 5/16 3/8 1/2 5/8
R410A oz per foot .25 .44 .60 1.15 1.95

Unit Check-Out Sheet | 19RZ CS Series Heat
8 733 922 031 (2014/03)Revised 03-14
UNIT CHECK-OUT SHEET
Customer Data
Customer Name _____________________________________________ Date ___________________________________
Address ______________________________________________________
_______________________________________________________________
Phone _______________________________________________________ Unit Number ___________________________
Unit Nameplate Data
Unit Make _________________________________________
Model Number ____________________________________ Serial Number ____________________________________
Refrigerant Charge (oz) __________________________
Compressor: RLA ____________________ LRA ___________________________
Blower Motor: FLA (or NPA) ___________ HP ____________________________
Maximum Fuse Size (Amps) ____________
Maximum Circuit Ampacity _____________
Operating Conditions
Cooling Mode Heating Mode
Entering / Leaving Air Temp _______________ / _____________ _______________ / _____________
Entering Air Measured at: ______________________________ ______________________________
Leaving Air Measured at: ______________________________ ______________________________
Entering / Leaving Fluid Temp _______________ / _____________ _______________ / _____________
Fluid Flow (gpm) ______________________________ ______________________________
Compressor Volts / Amps _______________ / _____________ _______________ / _____________
Blower Motor Volts / Amps _______________ / _____________ _______________ / _____________
Source Fluid Type ______________________________ ______________________________
Fluid Flow (gpm)* ______________________________ ______________________________
Fluid Side Pressure Drop* ______________________________ ______________________________
Suction / Discharge Pressure (psig)* _______________ / _____________ _______________ / _____________
Suction / Discharge Temp* _______________ / _____________ _______________ / _____________
Suction Superheat* ______________________________ ______________________________
Entering TXV / Cap Tube Temp* ______________________________ ______________________________
Liquid Subcooling* ______________________________ ______________________________
* Required for Troubleshooting ONLY
Auxiliary Heat
Unit Make __________________________________
Model Number: ______________________________ Serial Number _____________________________
Max Fuse Size (Amps) _______________________
Volts / Amps _______________________________
Entering Air Temperature _____________________
Leaving Air Temperature ______________________

20 | Troubleshooting RZ CS Series Heat Pump
RZ CS Series Heat Pump8 733 922 031 (2014/03) Subject to change without prior notice
TROUBLESHOOTING
Troubleshooting Information Solution
column may reflect a possible fault that
may be one of, or a combination of
causes and solutions. Check each cause
and adopt "process of elimination" and
or verification of each before making
any conclusion.
Unit Troubleshooting
Problem Possible Cause Checks and Correction
ENTIRE UNIT
DOES NOT RUN
Power Supply Off Apply power, close disconnect
Blown Fuse Replace fuse or reset circuit breaker. Check for correct fuses
Voltage Supply
Low
If voltage is below minimum voltage specified on unit data plate,
contact local power company.
Thermostat Set the fan to “ON”, the fan should run. Set thermostat to “COOL” and
lowest temperature setting, the unit should run in the cooling mode
(reversing valve energized). Set unit to “HEAT” and the highest
temperature setting, the unit should run in the heating mode. If neither
the blower or compressor run in all three cases, the thermostat could
be miswired or faulty. To ensure miswired or faulty thermostat verify 24
volts is available on the condensing section low voltage terminal strip
between “R” and “C”, “Y” and “C”, and “O” and “C”. If the blower does
not operate, verify 24 volts between terminals “G” and “C” in the air
handler. Replace the thermostat if defective.
UNIT OFF ON
HIGH PRESSURE
CONTROL
Discharge
pressure too high
In “COOLING” mode: Lack of or inadequate water flow. Entering water
temperature is too warm. Scaled or plugged condenser. In “HEATING”
mode: Lack of or inadequate air flow. Blower inoperative, clogged filter
or restrictions in duct work
Refrigerant
charge
The unit is overcharged with refrigerant. Reclaim refrigerant, evacuate
and recharge with factor recommended charge.
High pressure Check for defective or improperly calibrated high pressure switch.
UNIT OFF ON LOW
PRESSURE
CONTROL
Suction pressure
too low
In “COOLING” mode: Lack of or inadequate air flow. Entering air
temperature is too cold. Blower inoperative, clogged filter or
restrictions in duct work. In “HEATING” mode: Lack of or inadequate
water flow. Entering water temperature is too cold. Scaled or plugged
condenser.
Refrigerant
charge
The unit is low on refrigerant. Check for refrigerant leak, repair,
evacuate and recharge with factory recommended charge.
Low pressure
switch
Check for defective or improperly calibrated low pressure switch.
UNIT SHORT
CYCLES
Unit oversized Recalculate heating and or cooling loads.
Thermostat Thermostat installed near a supply air grill; relocate thermostat.
Readjust heat anticipator.
Wiring and
controls
Check for defective or improperly calibrated low pressure switch.