aquatherm AT600 Quick start guide

MEMBER
Pool
Heat
Pump
Manufacturers
Association
MEMBER
WARNING: Specifications may change without notice.
NATIONAL
POOL & SPA
INSTITUTE
NOTE: Installers should see separate installation manual !
Model
AT600
DIGITAL
LOGIC™
© 2006 Aquatherm Heat Pumps
SWIMMING POOL & SPA
HEAT PUMPS
OWNERS
OPERATIONAL MANUAL

A. Introduction ...........................................................................................Pages 2 - 3
1. Unit Exterior Description
2. How A Heat Pump Works
B. Heat Pump Description ........................................................................Pages 4 - 5
1. Control Panel Description
2. Optional Time Clcok Override Description
3. LED Display & Status Light Descriptions
C. Operational Instructions ......................................................................Pages 6 - 7
1. Water Flow & Water Pump Timer Setting
2. Thermostat Setting
3. Optional Time Clock Override Setting
4. Time Delay Modes
5. Normal Operation Indicators
6. Pool/Spa Covers (Blanket) Use
7. Spa Heating Suggestions
8. Defrost Mode Control
D. Owner Required Maintenance & Precautions .................................Pages 8 - 12
1. Air Flow & Service Clearances
2. Chemicals, Feeders & Water Balance
3. Owner Cleaning & Maintenance
4. Professional Service Requirements
5. Warranty Service Requirements & Notes
6. Operational Sequence & Troubleshooting Flow Chart
Table of Contents
Introduction
Congratulations on the purchase of your new swimming pool/spa heat pump. Utilizing
heat pump technology is the most efficent method of heating a swimming pool. Please
take a few minutes to read this owner’s manual to familiarize yourself with the operation
and features of the heat pump.
Please be sure to fill out the warranty card and send it back to us. If you have any ques-
tions regarding your heat pump, or if you have a need for service, please contact us at
our toll-free number listed below.
Important Information to Record
Installer Name ________________________________________________________
Installer Phone_______________________ Install Date ______________________
Model Number_______________________ Serial Number ____________________
2213 Andrea Lane Ft. Myers FL 33912
888-297-3826 239-482-0606
www.aquathermheatpumps.com
HEAT PUMPS
NOTICE
Technicians See Separate “Installation Manual”. Specifications may change without notice.

Unit Description
A swimming pool & spa heat pump
utilizes proven refrigerant technology
to capture the heat in the outside air
and transfers it to the pool water. Re-
frigerant is used because of its ability
to absorb and transfer heat energy.
The fan circulates air through the
outer evaporator air coil that acts as
a heat collector. The liquid refrigerant
in the air coil absorbs the available
heat in the ambient air, transforming
it into a gas. The refrigerant gas is
then pumped into the compressor.
When this warmed gas is com-
pressed, it intensifies or concentrates the heat, like a magnifying glass in the sun.
This intensely hot gas is then pumped into the heat exchanger condenser, where the
actual heat transfer takes place. As the pool water passes through the heat exchanger,
the hot gas gives up its heat to the cooler pool water. The refrigerant returns to a liquid
state and is pumped through the expansion valve then into the evaporator air coil to start
the process all over again.
How Efficient Is It ?
This graph is a operational cost comparison for
equal amounts of pool heat. As you can see
heat pump is the most efficient way to heat
your pool.
Compared to L.P. gas heaters, a heat pump
produces 5 to 6 times more heat for every $1.00
you spend on operation.
AIR DISCHARGE FAN
WARNING:
ROTATING BLADE
KEEP HANDS & HAIR
CLEAR!
CONTROLS with
LED READOUT
WATER OUT
2” MALE
THREADED
UNION WATER IN
2” MALE THREADED
UNION
DATA
PLATE
ELECTRICAL
INSTALLATION
PORT(S)
Page 3
How A Heat PumpWorks

HEATER ON/OFF: To start the heater press this button and it’s green light will come
on. To disable the heater press this button and its green light will go off.
THERMOSTAT BUTTONS: Pressing the + button will raise the set temperature.
Pressing the - button will lower the set temperature. When either button is pressed
the LED display will begin to flash. The flashing numbers indicate the thermostat
setting.
MODE SELECT BUTTONS-POOL or SPA: The heater has two thermostat modes
for two different desired temperature settings, one for pool mode and one for spa
mode. If you do not have a spa use the pool mode only. If you do have a spa, you
can connect two Jandy™ motorized plumbing valves. Therefore, when you select
either mode the motorized valves will turn to isolate the heater to either the pool or
spa. NOTE: There is a 30 second delay when switching pool/spa modes.
“OPTIONAL” WATER PUMP TIME CLOCK OVERRIDE OPERATION When the
T.C.O. button is set to the ON mode, the Time Clock Override feature is designed to
start the water pump whenever the pool requires heat. Once the pool is up to the set
temperature the heater will stop and then 5 minutes later the water pump will stop.
When this button is set to the OFF mode, the heater will operate only when the water
pump is running during the timed period set on the water pumps time clock.
NOTE: The time clock override works best if used during cooler weather conditions
where the pool is losing more than 8 to 10 degrees over night or when the pool is
being heated from “dead cold”.
NOTE: If the time clock override starts the water pump and the thermostat does not
continue to call for heat for at least 5 minutes, the control will shut the water pump and
heater off. Thereafter, it will not re-attempt to start the water pump for 4 hours. This
4 hour delay can be bypassed by pressing the T.C.O. button off then back on.
NOTE: When the T.C.O. button is activated while in “spa mode” the water pump
will run the entire time you are in spa mode. When you switch back to pool mode
there will be a 5 minute delay before the water pump shuts off. The T.C.O. option
is built into the heater at the factory and can not be added later.
Page 4
“Digital Logic” Digital Control Panel Information

GREEN POWER LIGHT:
This light indicates that the heater has control power.
WARNING: This is not a supply line power indicator and caution should be used since
more than one power disconnection may be required to isolate the heater electrically.
WARNING: If the optional Time Clock Override is installed, you must shut off the
water pumps main power disconnect as well to eliminate all power to the heater.
GREEN HEATING LIGHT:
This light indicates that the unit is heating and the compressor is running. The
compressor starts after a 3 to 5 minute time delay. NOTE: The water pump must
be running at the same time in order for the heater to run.
LED READOUTS:
When the unit has power, the LED will display the current water temperature. When
pressing the thermostat buttons the flashing readout will indicate the set temperature.
The following are LED code readouts for the internal sefety controls that regulate
the unit for various reasons.
LF = LOW WATER FLOW
This light indicates there is no water flow through the heater. The heater is
designed to shut off whenever the water pump is not pumping water through
the heater. If LF is on while the water pump is running, the water pump may
not be supplying enough flow for the heater to operate properly. During normal
operation the heater turns off and on with the water pump. LF will be displayed
whenever the water pump is off.
DF = DEFROST MODE
This readout indicates that the internal defrost safety control has disabled the
heater. During cold weather where the air temperature drops below approxi-
mately 45 to 50 degrees (depending on humidity), the low refrigerant pressure
switch (or defrost control) is designed to disable the compressor only. Once
the unit is in defrost mode the compressor will shut off for 1 hour while the fan
continues to help deice and warm the air coil. After 1 hour the unit will attempt
to restart. If the air temperature has increased to the operational range the
compressor will continue to run, otherwise the compressor will return to the defrost
mode for another 1 hour delay cycle.
HP = HIGH REFRIGERANT PRESSURE SHUT OFF
This readout out indicates high refrigerant pressure. The high refrigerant pres-
sure switch is designed to shut the compressor and fan off if a heat buildup
occurs for whatever reason. Typically, the high refrigerant pressure switch will
trip if the water flow through the heater is restricted. It may also trip if the air
flow is restricted through the heater. The only way to reset the unit after HP is
displayed is to shut the unit off then back on with the heater button.
Page 5
TIME DELAYS:
30 second compressor delay when switching pool/spa modes.
5 minute compressor delay when T.C.O. enables in pool mode.
5 minute T.C.O. off delay when: switching from spa to pool mode, when temperature
is reached in pool mode, or if LF (low water flow) is displayed on LED.
If water pump loses prime there will be a 3 minute compressor delay.

When heating the pool or spa you should check the following items as they are
all critical to the proper operation of the heater.
1. WATER FLOW
Make sure all pool filters and traps are clean since the unit requires a minimum
water flow in order to operate properly. The heater should and will not run un-
less the water pump is running. There is an internal water pressure switch that
disables the heater whenever the water pump is not supplying water flow.
2. WATER PUMP TIMER SETTING
Since the heat pump collects heat from the outside air, you want to set the water
pump timer to run during the hottest part of the day. If you are heating the pool
from “dead cold” you may need to set the water pump timer to run 24 hours
until the pool reaches temperature, then reset the timer for a normal run time.
Run times are determined by pool size, set pool/spa temperature and weather
conditions.
3. THERMOSTAT SETTING & MODE SELECT
BUTTONS
The LED display will show a constant readout of the
actual current water temperature. To set the desired
water temperature press either the + or - thermostat
buttons. While adjusting the set temperature, the
LED will flash. The flashing numbers will indicate
the thermostat setting.
If you have a spa you can press the spa mode button and set the desired spa
temperature. If you do not have a spa use the pool mode only.
4. OPTIONAL TIME CLOCK OVERRIDE SWITCH
The optional “Time Clock Override” control you can set the switch
turn this switch ON and the heater will start the water filter pump
automatically whenever the water temperature drops below the
thermostat setting.
This option is best used when heating the pool from “dead cold” and for main-
taining water temperatures during non timed periods where the pool is losing 8
to 10 degrees or more overnight. The heating mode select switch is best left in
the OFF position during the warmer parts of the swimming season. The optional
time clock override feature is built into the heater at the factory and can not be
Operational Instructions
Page 6

5. TIME DELAY MODE
This heater is equipped with an internal compressor time delay to allow the refrigerant to
settle during start-up or restart cycles. When the heater is started the fan will run but the
compressor will not start until the 3 to 5 minute delay has passed. The green heating light
will be on when the compressor is running. In some cases (when the heater is new or
during cold weather), it may be necessary to allow the unit to go through the time delay
several times before the unit will start. The unit will delay for other reasons noted below:
TIME DELAYS:
30 second compressor delay when switching pool/spa modes.
3 to 5 minute compressor delay when T.C.O. enables in pool mode.
5 minute T.C.O. off delay when: switching from spa to pool mode, when temperature is
reached in pool mode, or if LF (low water flow) is displayed on LED.
If water pump loses prime there will be a 3-5 minute compressor delay.
6. NORMAL OPERATION INDICATORS
When the fan and compressor are running, the unit will discharge cool air from the top.
The heater will produce condensation while running and is considered normal. It will
produce more condensation the more humid the ambient air is. The condensation will
exit the heater through the bottom drain ports.
7. POOL/SPA COVER USE
You can substantially reduce the heat loss and electrical consumption by utilizing a pool
cover or pool blanket. You can get higher water temperatures in less operational time
using a cover. If you keep the pool or spa covered whenever you are not swimming you
can typically reduce heat loss by as much as 80% and reduce heating costs as much as
50%. Using a cover during the initial heat up period will greatly reduce the operational
time needed.
8. SPA HEATING
When heating a spa it is advisable to not run the air blower or air inlet venturis during the
initial heat up time. Air blowers and venturis inject air into the water to create the spa
therapy action. During colder weather the air blower or inlet venturis will inject cold air
into the spa thus increasing heat demand. Leaving these items off until the spa reaches
the set temperature will reduce the heat up time. A cover is highly suggested for spa
heating.
9. DEFROST CONTROL IN COLD WEATHER
DF This readout indicates that the internal defrost safety control has disabled the heater.
During cold weather where the air temperature drops below approximately 45 to 50 de-
grees (depending on humidity), the low refrigerant pressure switch (or defrost control) is
designed to disable the compressor only. Once the unit is in defrost mode the compres-
sor will shut off for 1 hour while the fan continues to help deice and warm the air coil.
After 1 hour the unit will attempt to restart. If the air temperature has increased to the
operational range the compressor will continue to run, otherwise the compressor will return
to the defrost mode for another 1 hour delay cycle.
You my experience some frost or icing on the outer air coil in cold weather temperatures
and is considered normal. If the air coil ices up, shut the heater off, allow it to defrost and
wait for warmer weather to restart the heater. If you live in an area where the weather
is expected to drop below 45˚F to 50˚F for an extended period you should disable the
heater during those times. Page 7

1. Make sure the unit has a firm base. The heat pump will produce condensation
(water) while in operation. You will notice water coming from the bottom drain
ports when the unit is running. The condensation will increase as the outdoor
air humidity level increases.
Make sure the bottom drain ports do not become clogged with debris. Make
sure the run off water does not puddle inside the heater and does not undermine
the equipment base.
2. Keep the top air flow discharge & air flow intake area clear as shown here so
the air flow through the heater is not restricted. Make sure the unit can “breathe”
well. The cooler discharge air from the top should not accumulate and be drawn
into the side air intake coils. Keep all plants and shrubs trimmed away from the
heater. Make sure the front is accessible for future service.
3. Do not allow lawn sprinklers to spray on the heater in any way. Keep sprin-
kler heads away from the heat pump to prevent corrosion and damage. Use a
deflector if needed.
4. If the unit is installed under a steep roof pitch or under a roof valley that has
no gutter, a gutter or diverter should be fitted to prevent excessive water from
pouring through the unit.
Heat Pump Maintenance & Precautions
Page 8
1. Air Flow & Service Access
Clearances
AIR COIL
(on 3 Sides)
BASE
(CONCRETE OR
PREFAB)
FRONT
2” 6’
60”
BACK
12” 12”
12”
36”
AIR
COIL
FRONT

This heat pump is equipped with the highest marine grade cupronickel alloy heat ex-
changer that is designed to resist corrosion from normal pool water. The life and condition
of the heat exchanger is directly related to the pool water chemical balance and chemical
usage techniques. The following precautions are required to help prevent the possibil-
ity of corrosion damage to the heat exchanger. Chemical damage is not covered and
may void the warranty.
CHEMICAL FEEDERS & USAGE
1. Chemical feeders should be installed as far down-line of the heater as possible.
2. If a chemical feeder is installed at a level higher than the plumbing from the heater,
a Hartford loop must be installed that is at least as high as the top of the chemical
feeder.
3. Do not install a chemical feeder on the suction side of the filter system. Feeders and
chlorinators installed on the suction side will discharge concentrated chemical or chlorine
into the heat exchanger before it is diluted with the rest of the pool water.
4. NEVER PLACE CHEMICALS IN THE POOL or SPA SKIMMER !
Chemicals placed in the skimmer will feed concentrated chemicals or chlorine into the
heat exchanger before it is diluted with the rest of the pool water. Chemicals or chlorine
placed in the skimmer will dissolve and concentrate in the skimmer when the water pump
is off and then send a super concentrated chemical solution through the heater every
time the water pump restarts.
5. DO NOT STORE CHEMICALS NEAR THE HEATER !
6. POOL PUMP SUCTION AIR LEAKS
If a pool has a suction air leak, or the pool water level is causing the pump to suck
air into the pool plumbing, air turbulance in the heat exchanger can decrease heat
transfer and possibly cause damage to the heat exchanger.
7. PUMPS OVER 1.5 hp or 70 gpm
Be advised that water pumps rated over 1.5 H.P. or over 70 gallons per minute
must have a plumbing bypass added to the exterior heater piping as shown in the
technicians installation manual. Be aware of this when upgrading your existing
water pump.
Feeders, Chemicals & Water Balance
Page 9
MINIMUM WATER BALANCES
pH - 7.4 to 7.6
Chlorine - 1.0 to 5.0 p.p.m.
Alkalinity - 90 to 120 p.p.m.
Calcium - 200 to 350 p.p.m.
POOL WATER BALANCE
The following standardized water
balance values should be main-
tained to reduce the risk of corrosion
and/or mineral buildup in the heat
exchanger.
TO
POOL
CHLORINATOR PUMPS OVER 70 GPM
REQUIRE BYPASS HERE
6" TO 8"
HEAT
PUMP
FILTER
FROM
POOL
WATER
PUMP
OUT IN

Freezing Condition Precautions
In areas where extended freezing conditions exist, the heater must be plumbed
as shown here (and the installation manual), so
it can be winterized. Water left inside the heater
will freeze and cause damage.
This plumbing setup will allow the use of
pressurized air to clear the heat exchanger of
water in preparation for an extended freeze. This
should be done as part of your end of swimming
season winterizing.
In warmer southern climates where freezing
conditions are temporary, you should run the
water pump 24 hours a day to prevent the water
from freezing inside the heater. Freeze damage
is not covered and may void the warranty.
Owner Maintenance & Cleaning
1. The heat pump will produce condensation water run off while in operation.
Make sure the condensation drains in the bottom of the heater cabinet do not
become blocked with debris. The condensation run off may attract increased
plant growth and insects in the heat pump area, be sure to keep all plants trimmed
back and treat for insects as needed.
2. The outer air coil (located on three sides of the heater), should be kept free of
debris and buildup. A minimal air coil cleaning should be done as needed and at
least two times per year. If the heater is installed in a sandy or salty condition,
the air coil should be cleaned more frequently.
3. To clean the air coil SHUT OFF ALL POWER, then use a garden hose at low
pressure, (without a pressure nozzle) to lightly rinse the air coil in an up and down
motion. You can use a mild soap while rinsing to help neutralize and clean. DO
NOT spray water directly in heater at high pressure.
4. Cabinet surfaces can be wiped clean with a towel and mild cleaner.
Professional Maintenance
The heater should be serviced regularly like any other machine. A factory au-
thorized, licensed air conditioning or mechanical contractor should perform the
following maintenance procedures periodically.
1. Oil the fan motor.
2. Check the refrigerant charge.
3. Check the amp. draw.
4. Check all electrical supply connections & breakers.
5. Clean the air coil with approved solution.
6. Clean the interior cabinet bottom of debris.
7. Spray internal components with lubricant.
8. Inspect the installation including chemical feeder placement.
9. Inspect sprinklers to be sure the heater is not being sprayed.
10. Inspect for insect nests in and around the heat pump and treat.
Page 10
Contact the
manuafacturer at
888-297-3826 for
factory
authorized
service centers in
your area.

Water Pump
Starts Flowing
Water Pressure
SW Closes
Thermostat
Sensor
Heater
Stays Off
Low Pressure
Switch
Low Pressure
Switch Opens
LF displayed on LED
Low Pressure
SW Closed
All OK
LF Readout
Displayed on LED
T-Stat Relay
Closes
High Pressure
Switch
High Pressure
SW Closed
All OK
High Pressure
Switch Open
Heater Shuts Off
HP Displayed
Too Much Refrig.
or Low Water Flow
or Bad Hi Switch
Fan Starts
To Run, Green
Heating Light On
220V Power
To Heater
Green Power Light
On
Water Rises To
Set Temp.
Water Press. SW
Stays Open
No Water Flow
To Heater or
Bad Water SW
Compressor Runs
or 3 to 5 Min.
Delay Activates
Heater & Green
Heating
Light Go Off
Water Pump
Timer Activates
Compressor Stops
Fan Runs
T-Stat Relay
Does Not Close
Heater Does
Not Activate
After Delay Period
Try Again or
Possible Bad
Time Delay
Possible Bad
T-Stat Board, Pot
or Sensor
1 Hour Time
Delay Activates
Water Temperature
is Below Setting
Water
Temperature
is Above Setting
Compressor
Starts - Heating
Light ON
Time Delay Passes or
Air Temp. Increases
Safety Control Resets
Compressor
Restarts
or Below 45 to 50˚F
Air Temp or
Bad Low Press.
or Below 45 to 50
Deg. Air Temp
Operational Sequence & Troubleshooting Flow Chart
for “Digital Logic” Digital Control Models
TIME DELAYS
30 second compressor delay when switching pool/spa modes.
5 minute compressor delay when T.C.O. enables in pool mode.
5 minute T.C.O. off delay when: switching from spa to pool mode, when temperature
is reached in pool mode, or if LF (low water flow) is displayed on LED.
If water pump loses prime there will be a 3 minute compressor delay.
Page 11

Warranty Service
Before calling for warranty service you should check the following:
1. Clean all filters and traps in the pool circulation system. Low water flow will cause the
unit to shut down or cycle.
2. Check and adjust all water flow valves and adjust to the proper positions to insure
proper water flow through the heater.
3. Check the water pump timer setting to insure there is enough time allotted for a proper
heating cycle.
4. Check all circuit breakers and disconnects. Note: More than one disconnect may be
required to shut off or turn on power to the heater.
5. Confirm that all heater controls, thermostat, thermostat selector switch, reset tripper,
and optional auto heat switch (if so equipped), are in the correct position.
6. If any 3rd party control devices are installed on the pool/spa system make sure they are
functioning properly. Factory service technicians will not diagnose 3rd party external
control devices. All external controls are disconnected during warranty service and
the heater is diagnosed as manufactured then reconnected.
7. The limited factory warranty does not cover damage or conditions caused by but not
limited to the following:
Improper installation.
Improper use.
Inadequate run time on the water pump timer.
Improper water flow to the heater.
Conditions caused or associated with 3rd party external controls.
Chemical damage or improper water balance.
Sprinkler damage.
Roof run off damage.
Freeze damage or operation damage during freezing conditions.
Salt and/or sand/debris damage.
Lack of maintenance and/or cleaning.
Unauthorized servicing of the heater during the warranty period.
Normal rusting and oxidation of metal components.
Non warranty service calls such as inspections, maintenance, or problems unre-
lated to the heater as it was manufactured are not covered under the warranty.
8. You can contact the factory @ 888-297-3826 to be pre-qualified and scheduled with
a factory authorized service center in your area. Have your model number, serial
number and installation date ready.
Important Notes:
The heater will not heat faster if you turn the thermostat all the way up. The heater will
never run without water running through it from the pool/spa filter pump. When the heater
is started the fan will run right away. The compressor will start after a 5 to 7 minute delay.
The heating light will come on only when the compressor is running.
The heater will produce condensation at a steady rate. The condensation exits the heater
from the bottom drains. The more humidity the more condensation. The thermostat is
accurate within three degrees and may not always match exactly to the degree numbers
printed on the control panel as it is effected by the humidity and other factors. The heater is
designed to shut off in defrost mode when the air temperature drop below 45˚F to 50˚F.
Specifications may change without notice.
© 2006 Aquatherm Heat Pumps