Introduction
Nova Kool's refrigeration systems are designed to run efficiently from AC Shore Power,
Battery Power, or Solar Electric Power.
The Nova Kool custom refrigeration system includes the following:
1) condensing unit c/w compressor, fan cooled condenser, and reusable quick connect
fittings.
2) an evaporator (cold plates) made up of three plates. The plates come complete with a
capillary tube, heat exchanger, refrigerant lines (12') and quick connect fittings to
attach to the condensing unit. It is available in two models; the RT6 freezer box or the
"F" Plate configuration.
3) the third component to complete the installation is the system thermostat. The
enclosure c/w thermostat and knob can be mounted inside the refrigerator or out, but the
small diameter sensing tube must be attached to the cold plates inside the fridge or
freezer.
The unit
is charged with a CFC free (R134a) refrigerant.
Our unit features a reciprocating compressor which is very efficient. While running, it
uses less power than a 60 watt light bulb.
This unit has built in battery protection. This feature is designed to help protect the
battery from damage due to accidental deep discharge.
Nova Kool's refrigeration systems are designed to run efficiently from AC Shore Power,
Battery Power, or Solar Electric Power.
Operation
Our units are easy to operate. The temperature inside your refrigerator is controlled
by the thermostat. This thermostat is a full range thermostat that will maintain your unit
at the temperature you desire. Turning the control all the way to the right (clockwise)
will give you the coldest position, and turning to the left will give you a warmer
temperature in the fridge. The control is also an on/off switch when you turn it to the
"O" position (hard left). A good setting to start with is #2.
Defrosting
The frequency of defrost depends on the usage, (door openings) and ambient (outside)
temperatures.
It is time to defrost when the refrigerator builds up 1/4 of an inch of ice on each
side of the cold plates.
The best way to defrost the refrigerator is to remove all the food and place a towel
inside the fridge on the bottom of the cabinet (s). Turn the thermostat to the
"O" position.
Never use a knife to scrape ice from the cold plate. This will rupture the cold plate
and let the refrigerant escape.
Cleaning
The best
time to clean the fridge is after a defrost. Wipe the inside clean using a non abrasive
cleaner (watered down) for the hard to clean stains.
We recommend baking soda as a cleaner.
The condenser may
collect lint and dust on the fins. If you notice your refrigerator running longer than
normal, clean the condenser (every few years).
The condenser is located on the condensing unit base, and can be cleaned by using a
bottle brush and brushing vertically from top to bottom on the face of the condenser.
An alternative method is to vacuum the condenser. Be very careful not to damage the
fins because they are aluminum and will bend easily.
Ventilation
All refrigerators, regardless of the make, are heat-transfer machines. They transfer
the heat from the inside of the fridge to the outside of the fridge. If adequate
ventilation is provided, the compressor will operate more efficiently, and use less power
.
If the compressor is installed in a hot room (engine room) , it should
be located in the open with no enclosure to obstruct air flow to the unit, or cause
condenser air to be re-circulated.
If the unit is mounted in a closed area (cupboard or locker), there must be two holes
provided; one for cool air to be pulled in by the fan and the other to allow the warm air
to vent from the enclosure. The size of the opening must be at least 7"x7". The
inlet must be ducted (separate passageway) so the air is drawn through the condenser and
blown across the compressor.
If a decorative grill is to be placed over any of the ventilation openings the size of
the opening must be increased in order to still provide 50 sq. inches of free
unobstructed area.
To test the effectiveness of the ventilation, measure the exhaust air inside the
enclosure. The temperature should be no more than 5 degrees higher than the air entering
the enclosure (ambient air temp).
Electrical Hook up
To determine the size of the wire to be used, measure the maximum length of wire to
connect one of the leads from the electronic unit (on the back of the refrigerator) to the
battery. Using the chart below, size your wire accordingly. The table is based on a 3%
voltage drop.
|
Wire Size
|
Max. lead length in feet**
|
|
AWG
|
12VDC units
|
24VDC units
|
|
10
|
5'
|
20'
|
|
8
|
15'
|
30'
|
|
6
|
30'
|
45'
|
|
4
|
45'
|
60'
|
** Length is the distance between the electronic unit and the
battery
The circuit breaker must
be a 20 amp capacity on the DC side and a 5 amp capacity on the (optional) AC side.
Failure to size the wire or breaker correctly (too small) may cause a premature shut
down of the refrigerator by the Battery Protection Device.
We recommend that the refrigerator have its own circuit, without any other appliances
connected to the same wires.
Using the COMMON BUS for the refrigerator wiring can sometimes cause radio
frequency noise and interference.
FUSES
Nova Kool
recommends the use of a 15 Amp Fuse (12 VDC) or a 7.5 Amp Fuse (24 VDC) as near as
possible to the DC source.
On the optional AC power supply a 4 amp (110 volt) or a 2 amp (220 volt) glass fuse,
can be found under the black fuse holder cap.
Power supply for AC/DC Refrigeration systems
Wiring
diagram for DC only Refrigerators
1 - Electronic Unit
2 - Battery
3 - Main switch (optional)
5 - Fan (optional)
6 - Thermostat
7 - Resistor for pre-setting speed
8 - Resistor for pre-setting battery protection
voltage (optional)
9 - Fuse (Field Installed)
10 - Terminal Block
11 - Light (optional)
12 - Door Switch (optional)
Standard battery protection settings
- 12 V cut-out
- 10.4V
|
- 12 V cut-in
- 11.7V
|
- 24 V cut-out
- 22.8V
|
- 24 V cut-in
- 24.2V
|
Trouble-Shooting Guide
| |
|
YES |
NO |
| 1 |
Turn power on and turn thermostat to "7"
position |
Go to #2 |
|
| 2 |
Is the compressor running? (put your hand on top to feel
slight vibration to be sure). |
Go to #14 |
Go to #3 |
| 3 |
DC Breaker is in the "on" position &
optional fuse is good? |
Go to #5 |
Go to #4 |
| 4 |
Replace fuse or turn breaker "on". Does fuse
or breaker blow? |
Go to #6 |
Go to #5 |
| 5 |
Check voltage at the refrigerator "+" &
"-" terminals on the black module. Is it over 12 VDC? |
Go to #7 |
Go to #6 - (Go to 17 on
AC/DC models) |
| 6 |
Check batteries, wiring and connections to the
refrigerator for fault, corrosion, proper wire sizing and correct the problem. |
Go to #1 |
|
| 7 |
Put a jumper wire between terminals "C" &
"T". Is the compressor running now? |
Go to #11 |
Go to #8 |
| 8 |
Disconnect power. Remove electronic module (Philips
screw beside terminal designation label will require removal). Disconnect the plug.
Measure resistance (ohms) between each of the three compressor terminal pins. Is the
measured resistance APPROXIMATELY the same? |
Go to #9 |
Go to #10 |
| 9 |
Replace Electronic Module. |
Go to #1 |
|
| 10 |
Have compressor replaced by qualified appliance
technician who has the ability to evacuate and recharge the system. This is seldom
necessary so please be sure and if possible contact Nova Kool for further instruction
beforehand. |
|
|
| 11 |
Check wiring to thermostat with ohm meter to ensure
there is continuity. (No broken or damaged wires or connectors). Is the wiring okay? |
Go to #13 |
Go to #12 |
| 12 |
Disconnect power. Repair or replace wiring as necessary |
Go to #1 |
|
| 13 |
Replace thermostat. |
Go to #1 |
|
| 14 |
Is the fan running? |
Go to #16 |
Go to #19 |
| 15 |
Provide extra ventilation (i.e.. hatch open, Lazerette
open - where air can escape). After an hour is it refrigerating? |
Go to #16 |
Go to #19 |
| 16 |
Check that adequate ventilation has been provided. See
ventilation suggestion on Page 4 of this manual. Add ventilation as required. |
|
|
| 17 |
Have a qualified appliance technician determine if there
is a refrigerant leak or a compressor with a mechanical problem. |
|
|
| 18 |
Check voltage at "+" and "F"
terminals. Is there 12 VDC (or 24 VDC)? |
Go to #19 |
Go to #5 |
| 19 |
Replace fan. |
|
|
|
FROM 20 TO 27
APPLIES TO AC/DC MODELS ONLY! |
|
|
| 20 |
Switch DC breaker off and AC breaker on. Does the
refrigerator run? |
Go to #18 |
Go to #19 |
| 21 |
Turn DC breaker on and check DC voltage on Terminal
Block located on side of gray AC power supply. Is it above 12 VDC (or 24VDC)? |
Go to #24 |
Go to #6 |
| 22 |
Check fuse on gray AC power supply (4 amp 110V and 2 amp
220V). Is the fuse good? |
Go to #22 |
Go to #20 |
| 23 |
Remove power supply and determine if there are any
indications of a short circuit. If no, replace fuse. Does fuse blow again? |
Go to #24 |
Go to #21 |
| 24 |
Check DC voltage output of power supply at black module
terminals "+" & "-". Is it above 12 VDC (or 24 VDC)? |
Go to #18 |
Go to #24 |
| 25 |
Is 110V (or 220V) available at the AC plug? |
Go to #21 |
Go to #23 |
| 26 |
Check plug, wiring, breaker, shore power or genset for
damage or fault. Repair or replace as required. |
Go to #17 |
|
27 |
Replace gray AC power supply. |
|
|
Typical AC/DC Refrigerator
1
- Electronic Unit
2 - Battery
3 - Main switch (optional)
4 - Power Supply (optional)
5 - Fan (optional)
6 - Thermostat
7 - Resistor for pre-setting speed
8 - Resistor for pre-setting
battery protection voltage (optional)
9 - Fuse
10 - Terminal Block
11 - Light (optional
12 - Door Switch (optional)
Refrigerant Charge & Sealed System
Your Nova Kool is charged with R134a. This is a environmentally safe refrigerant with a
"O" Ozone Depletion Potential.
It is used by most of the domestic refrigeration and appliance repair companies and
manufacturers.
If you need to repair the closed sealed system, use a qualified appliance refrigeration
person. This is seldom necessary so be sure first, and before any arrangement is made
contact Nova Kool.
Operational Sequence
When the thermostat is turned on (you should hear a click) the compressor should try to
start. It is not uncommon to hear a small squeak when it tries to start. If it does not
start on the first attempt it will continue to try every 40 seconds.
If, for some reason, the compressor becomes overloaded it will go through this cycle
and the fan will continue to run during the 40 seconds.
When the thermostat is satisfied, the compressor and fan (optional) shut down.
- Before doing warranty work contact your dealer or
- Nova Kool at 604-984-7764 /www.novakool.com
Installing the evaporator plates
"F" Plates or the RT6 Freezer Box
Most custom marine refrigerators are designed top opening because cold air is heavier
than warm air. With this design the door can be left open with out significantly
increasing the temperature in the freezer. For the same reason, the cold plates must be
mounted with their top edges near the top of the refrigerator, on the interior wall .
Cooling will only take place below the top portion of the cold plates.
Nova Kool systems are designed to work as a freezer or as a refrigerator. Turn the
thermostat "warm" and the space becomes a refrigerator. Turn the thermostat
"cold" the space becomes a freezer (providing the space is not too large).
To use our system for a REMOTE combination, mount the cold plates in the section
designed as a freezer. Install a 1" insulated partition between the fridge and the
freezer, with a variable sized hole in the bottom (approximately 1-1/2" round).
Remove the tie strap that hold the two plates together & replace with mounting
screws through the first place, through the nylon space and through the second plate. At
this point you can use one or two spacers to keep the plates from the wall. Depending on
the temperature of your box, the third plate may not fully frost.

This hole will allow the cold freezer air into the refrigerator side of the cooler, and
as the air warms it will rise over the top of the partition and start the natural
circulation flow over again.
The size of your refrigerator or freezer area that you are able to refrigerate, will
depend upon the amount of insulation surrounding the enclosure.
The RT6 Freezer box can be mounted horizontally or vertically: the higher it is placed
in the cooler the more efficient the refrigerator will operate. Mounting upright is much
more convenient.
Installation check list
1) Select a location for the LT200 condensing unit. The lines are 12 feet in length.
Check the laying length into the refrigerator , make sure you have not mounted the
evaporator further from the unit than the line set will allow. Position the unit so the
electrical connections and the quick connect fittings are easily accessible. You will have
to tighten the refrigerant line quick connect to the condensing unit line quick connects
so leave room to swing two large wrenches.
2) Design your ventilation system. If it is necessary you can install an extra fan
(same type as the one on the unit) to terminals "+" & "F". If you
use an extra fan it will use approximately 3 watt hrs./hr. and run only when your unit
runs.
.
Shows Nova Kool RT6 mounted near the top of the freezer section.
3) The "F" Plate evaporator plates are connected together with tubing to
allow an 18" spread width. They can be mounted across from each other or adjacent to
one another inside the cooler. They should be mounted 1" from the interior top side
of the refrigerator. The plates can be mounted in any physical position. When the plates
are permanently mounted, make sure the copper tube is not touching the aluminum tube due
to electrolysis.
4) Make a cardboard template from the cold plate mounting holes and select the mounting
position for both F plates (or single RT6 assembly). The copper tubing should remain
coiled. Next, select the most convenient location for the tubing exit hole. Drill a 2
" hole using a hole saw.
5)Uncoil the tubing and feed the couplers and copper tubing through the hole, to the
outside of the refrigerator. Fasten the plates using the spacers and screws provided, to
the area previously marked.
Use a minimum of one spacer to keep the evaporator plates away from the cooler wall.
6) Starting just inside the refrigerator, the foam tubing should run on the outside of
the tubing in a direction towards the condensing unit. The exit hole must be sealed air
tight on the outside and fit loosely on the inside, with fiberglass insulation in between.
Moisture always moves to the coldest point; this is why it is important to seal on the
outside of the tubing hole. Also insure the interior liner of the fridge is sealed on all
lower seams in order to prevent defrost water from leaking into the insulation.
7) Carefully and neatly run the tubing to the condensing unit. Make long radius bends
if possible. To make a tight bend of 90°, support the copper with both thumbs while
making the bend. Excess tubing can be rolled back up and stored out of the way, (do not
cut the tubing, it has a refrigerant charge in it). Make as few bends in the tubing as
possible because it work hardens with each bend. Three bends are usually considered
maximum.
8) Connect the "quick connects" from the line set to the condensing unit.
They are male and female and impossible to connect backwards. The connectors are designed
to be put together and taken apart with out the loss of refrigerant. (Do not be disturbed
to see wrench marks on the connectors, because we connect them during our 12 hour unit
test run.
Shows Nova Kool LT200 installed in ventilated
Lazerette.
To connect:
a) put a small amount of oil or WD40 on the male coupling, and between the swivel part
of the female nut.
b) connect and turn by hand till tight, (approximately 2 turns).
c) use two 12" crescent type wrenches to tighten couplings together. Be sure not
to let the copper tubing twist, or the unit will be damaged.
Use one wrench on each side of the coupling.
9) The thermostat is
installed in a small white box and is complete with 14' of wire. The thermostat connects
to C & T on the module (polarity does not make any difference with the thermostat, but
it does with all other connections)
You can mount the thermostat box inside or outside the refrigerator space, but the last
2" of the 48" sensing line must be connected to the cold plates. Connect the
sensing tube to the cold plate by placing 2" of it under the 1"x2 " plate
on the second cold plate.
Shows completed installation.
All Power Consumption Graphs based on 7.5 cu. ft. size, insulated with 2" Urethane
Foam or 3" Polystyrene Foam.