Domestic and commercial refrigerators may be rated in kJ/s, or Btu/h of cooling. Commercial refrigerators in North America are mostly rated in tons of refrigeration, but elsewhere in kW. One ton of refrigeration capacity can freeze one short ton of water at 0 °C (32 °F) in 24 hours. Based on that: A much less common definition is: 1 tonne of refrigeration is the rate of heat removal required to freeze a metric ton (i.e., 1000kg) of water at 0 °C in 24 hours. Based on the heat of fusion being 333.55 kJ/kg, 1 tonne of refrigeration = 13,898 kJ/h = 3.861kW. As can be seen, 1 tonne of refrigeration is 10% larger than 1 ton of refrigeration.

Most residential air conditioning units range in capacity from about 1 to 5 tons of refrigeration.

Locate refrigerators away from heat sources like your range, a radiator, or a sunny window.

Never run frost-free refrigerators with freezer compartments in unheated areas with air temperature below 15 degrees C unless they are specially designed for such conditions. When the air temperature goes below 15 F, the compressor runs less, keeping temperatures in the refrigerator compartment cold enough for fresh food but not cold enough in the freezer compartment to keep food quality there. At air temperatures below 4 C, the compressor stops running, so the freezer compartment rises to air temperature and food thaws and spoils. Also below 0 C, water melted during the automatic defrost cycle may freeze again and block air passages.

For seasonal homes with heat left on at very low temperatures, or long winter vacations with heat turned down in home, remove all food, unplug the refrigerator, clean thoroughly, dry, and leave door ajar so air can circulate. Be sure no child can get into empty refrigerator in your absence and become trapped! If you can't use up food, give it away or throw it away; food that spoils in a refrigerator can create odours that may require discarding the refrigerator!

For short vacations, leave the refrigerator on but use up or discard perishable food, and if you have an ice maker, turn off the mechanism and water line following your manual directions.

If you have a chilled water dispenser, and room temperatures may go below freezing (as in moving, winter trip) shut off water and drain the water tank following the directions in your appliance manual.

Do not cram the refrigerator so full that cold air can't circulate freely to chill food. Cover or wrap all foods stored, especially in frost-free models, to prevent drying out, and transfer of odours.

In models that need defrosting, do not use electric defrosters or other hot objects where they can touch plastic liners or parts; they could melt. Always unplug the refrigerator before defrosting. Never use sharp objects which could damage the evaporator coils.

Clean the refrigerator compartment regularly, even though it does not require defrosting. Turn it off and unplug. Remove all food and removable interior parts. Wash with a solution of 1-2 tablespoons baking soda in 1 quart warm water. Rinse and wipe dry. Wash removable glass shelves and plastic parts in warm detergent solution, rinse and wipe dry. Do not put either glass or plastic in hot water; they may crack, especially if cold. Clean the door gasket with detergent solution; rinse and dry.

Occasionally clean the freezer compartment following manual instructions.

Wash the exterior of the cabinet with detergent solution; rinse and dry. A creamy appliance wax may be used occasionally to protect the painted exterior and make spots easier to wipe off.

Wipe up spills in the refrigerator promptly to avoid staining and odours.

Several of the plastics used for interior parts of the refrigerator are easily stained by berries, fruits, and other coloured foods and absorb and retain odours. So tightly wrap or cover stored foods and remove "old" foods before they spoil.

These plastics may soften at high temperatures, so never put boiling or hot water in them. They may be damaged by various household chemicals, so never use cleaning waxes, spray-on cleaners, or concentrated chlorine bleach on them. Follow your manual directions for cleaning the different plastic drawers, shelves, etc. If you do not have a manual, be safe by using a mild detergent (a hand dish washing liquid) and lukewarm water solution, or a baking soda and water solution for cleaning. NEVER use abrasives like scouring powder or scouring pads, as these plastics are easily scratched.

Occasionally vacuum (or brush) dust from condenser, usually under the front bottom grille (see manual for location and directions). Also at the same time, wash the plastic pan which collects water from automatic defrosting and replace it in the same location.

Unpleasant odours develop either from improper storage of food or from spoilage.

To Remove Odours
Odours may be caused by food left too long, "strong" foods not covered or packaged tightly, by a drip pan that needs cleaning, or by food spoiling when power goes off while the owner is away on vacation. A preventive measure is getting someone to check your home every day or so, or after a power outage in your area.

1. Remove all items from the refrigerator or freezer. Throw out any spoiled foods. Take out removable parts and wash them and the door gasket with mild detergent in warm water. Rinse well and wipe dry.

Wash the interior walls and door liner with a solution of 1-2 table spoonful of baking soda and 1 litre warm water, and wipe dry. Leave the door open and let it air out well, with a fan directed toward inside, and opened windows if the climate permits. If the odour still remains, try one or all of the following means of odour removal.

• Spread baking soda out on shallow pans (like shallow glass casserole dishes, pie plates, or jelly roll pans lined with foil) and put pans on the shelves to absorb odors, or on the bottom and in baskets of chest freezers. Leave open and unplugged.

Buy activated charcoal (which is specially treated to remove odour molecules from air) at some department store housewares sections, appliance stores, or pet shops. Spread out on shallow pans and put on the shelves of the refrigerator. Turn the refrigerator on its low setting and run empty for a few days so odors will be absorbed.

Spread cat litter in a shallow pan in the cabinet, turn on and run empty a few days. If the odour is disappearing but is not all gone, replace old litter with fresh litter.

Pour several ounces of imitation vanilla (not pure extract) in a shallow saucer, put on the shelf and let the refrigerator run empty a few days.

Put fresh ground coffee in cereal bowls inside the refrigerator and let it run empty several days. A slight coffee odour may remain, but will disappear after washing again with baking soda solution.

Pack each refrigerator shelf with crumpled newspaper. Set a cup of water on the top shelf or sprinkle the newspaper lightly with water. Allow the refrigerator to run for approximately 5-6 days. This method takes a bit longer but has been effective in removal of strong odours.

Buy a commercial odour remover, and follow instructions exactly. Hospital supply stores carry Chemical Hospital Disinfectant and Deodorant Spray. Spray into the cabinet and quickly shut the door. Repeat.

1. If none of these methods removes all the odor, then it has probably penetrated into the insulation. Contact an appliance service company for an estimate on the cost of removing the liner and replacing the insulation. If the cost is too high, you may prefer to get a new appliance. The old refriegerator could be used for occasional cooling of soda pop where the odour will not get into the beverage.

WARNING! If the refrigerator cannot be salvaged and is discarded, remove the door or lid. This is the law in many areas, to prevent deaths of children who may hide in the cabinet and suffocate.

 

How to Test A Domestic Single phase (220 Volt) Refrigeration Compressor

Some Basics First

These Refrigeration Compressor have a Starting Capacitor (Normally between 60 and 80 uf (Micro-farads )

Unplug the refrigerator or turn off the breaker that powers it. Since you will have to get to the inside of the condenser unit of the refrigerator anyway, I would recommend you unplug it

On the side of the condenser unit you should see the terminal box with wires coming out of it. Remove the cover from this box. The cover will be held in place by either screws or retaining clips.

With the cover off, you should see the Start relay, and one or two Capacitors, one WILL be about 60 to 80 uf this is the Start Capacitor

If there is another Capacitor it will be in the range of 10 to 30 uf this is a Running Capacitor and has little to do with Stating the Compressor

There are a number of tests that you can perform to check if the Refrigeration compressor in faulty

Examine the Connections especially on the Compressor

The Smaller commercial compressor have their Starting relays on the compressor with the Start Capacitor outside the terminal box, proceed to do the normal checks on the Start and Clixton /Overload relay

Use the long-nose pliers to pull the wire connector off of the relay. Pull it off by gripping the connector, NOT the wire. Inspect both the connector and the relay for any signs of corrosion. If there are any, then you should replace the part.

Use the long-nose pliers to pull the wire connector off of the relay. Pull it off by gripping the connector, NOT the wire. Inspect both the connector and the relay for any signs of corrosion or heat damage. If there are any, then you should replace.

The bigger units have a starter box housing the Start Relay, and terminals for the condenser fan and Pressure switch

Test the Start Capacitor.

Be Very Careful here you are working With Voltage and Capacitance you are in danger of Electrical shock if you are negligent

If you have a megger, Set it to 500 Volts

Charge the capacitor using the megger

See if the Capacitor can hold a charge , wait a short while then short the terminals out , The Capacitor should Discharge in a reasonably load bang and Flash if the capacitor is healthy

A health Capacitor will charge and slowly indicate on the megger that the capacitor is Zero conductive at empty and Moves to infinite conductivity as the capacitor becomes charged

If the refrigeration compressor Fails to start up due to a short term mechanical error try increasing the valve of your micro-farads of the start compressor say to 100 or 120uf, this bang is normally adequate to get the a healthy but impaired compressor going again.

Test the RUN Capacitor

If you have a megger, Set it to 500 Volts

Charge the capacitor using the megger

See if the Capacitor can hold a charge , wait a short while then short the terminals out , The Capacitor should Discharge with a lesser load bang and Flash if the capacitor is healthy. Remember that the run capacitor is a much smaller Capacitor than the Start Capacitor

A health Capacitor will charge and slowly indicate on the megger that the capacitor is Zero conductive at empty and Moves to infinite conductivity as the capacitor becomes charged

A faulty Run capacitor shows itself in the compressor drawing to many amps ( current to high) or a healthy compressor stalling for no reason

Winding Burnt to earth

Set your Multimeter to Max Ohms reading(You know, the one that wants to read if you just touch the Probe terminals) or Meggar to 500v .Touch one of the tester's probes to Earth or a copper pipe and leave it there. (Test the meter to make sure its set correctly) Then, use the other probe to touch first one then the other terminals and finally the last one.

The tester should display a reading of "zero" ohms or Clear reading for each test. The compressor is in Order

Any reading here indicates that the wiring is no longer insulated and touching earth. The compressor has to be failed

Winding Burnt Between Coils / Windings

On the Compressor you will see three terminal points randomly number them a,b,c or 1,2,3, or left, right, top, Whatever......

Set your Multimeter to read Ohms reading or set your Meggar to Ohms . (Test the meter to make sure its set correctly) Then, Set one probe to touch first one "a" or "1" or whatever Now leaving this probe on this terminal take the other probe and Test:

Ohm reading "a" to "b" = record reading a-b

Ohm Reading "a" to "c" = record reading a-c

NOW MOVE the Fixed probe to the Next terminal Say "b"

Ohm reading "b" to "c" = record reading b-c

You now have three Ohm readings

a-b =

a-c =

b-c =

Now some Rules

The highest reading MUST be equal to the other two reading ADDED together

The highest reading is a reference to two terminal (Say "b-c") the terminal that is not mentioned in this reference (this case "a") is the Common or the terminal that you connect the Clixton or Overload too.

The Second highest Ohm reading is the Run terminal

The lowest Ohm Reading is the Start Terminal

Conclusions

If the Reading DO NOT balance then the windings are burnt between coils and compressor has to be failed

The reading must all be in the same ball park say 4.5.9 (4+5=9) or 12, 15, 27 (12+15=27) if not then the compressor is giving false reading and must be failed.

If you really clever and are sure of your Common, Start and Run terminals, you can try start the compressor manually by Connecting a Neutral to the common terminal, a jumper between Run and Start. Put power on then as the refrigeration compressor then as the compressor labours, remove the jumper leaving Line/Live on run and neutral on Common, the compressor should run very comfortably (Keep a close watch on your AMPS)

Compressor Seized

If you have done all the above tests and the compressor Passes, and still find that the Refrigeration Compressor Amps (Current) is to high or the compressor will not rotate then in all likelihood the compressor is seized or failing mechanically, her are the logical symptoms

Refrigeration Compressor runs for a short while before the clixton overload switched the compressor off, The compressor starts up after a short while and the cycle is repeated On /OFF (Short cycling)

The Refrigeration Compressor merely hums and does not run

The compressor runs drawing abnormally high current (Amps)

Compressor valves Inefficient

To test Refrigeration Compressor Suction Valves

Disconnect all pipework from the Hi-side / Discharge pipe of the Refrigeration Compressor

Connect your Refrigeration Gauge Low side Gauge to the Suction /Low-side of the compressor

Open all Valves on your Refrigeration Gauges

Start the refrigeration compressor

Close the Low side Valve on your Gauge and observe to what level of vacuum the Refrigeration Compressor pulls the Gauge.

A good compressor will pull the Gauges into a deep Vacuum , A Faulty Compressor will hardly be able to Draw a vacuum or even just get the Gauge down to Zero

To test Refrigeration Compressor Delivery / Hi Side / Discharge Valves

Be Very Careful in Performing this Test. Major injury and/ or Damage to equipment can Occur

Disconnect all Pipework from the Suction / Low -side of the compressor

Connect the HIGH SIDE GAUGE of your Refrigeration Gauges to the Hi Side / Discharge Side of the compressor

OPEN all Valves on your Refrigeration Gauges

Start the compressor

GENTLY close you Refrigeration gauge Valve to throttle the Delivery of the compressor WATCH the Gauge slowly climb as you slowly throttle the delivery

A good Compressor Discharge Valves will very quickly MAX you Gauge out.

A Refrigeration Compressor with burnt / bent or leaky valves will struggle to get the High side gauge to go to its Maximum reading

 

Maneurop Refrigeration Compressors
Maneurop® MT and MTZ series compressors are of the hermetic reciprocating type and are designed for medium and high evaporating temperature applications. The MT series is designed for use with the "traditional" R22 refrigerant, using Danfoss Maneurop® mineral oil 160P as lubricant. The MT series can also be applied with several R22 based refrigerant blends (substitute refrigerants), using 160 ABM alkylbenzene as lubricant. The MTZ series is specifically designed for use with the HFC refrigerants R407C, R134a, R404A, and R507, using 160PZ polyester oil as lubricant.

See here for the full Specification sheet for the Maneurop Range of Refrigeration Compressors

MT and MTZ compressors have a large internal free volume that protects against the risk of liquid refrigerant hammering when liquid refrigerant enters the compressor. MT and MTZ compressors are fully suction-gas cooled. This means that no additional compressor cooling is required and this allows the compressors to be insulated with acoustic jackets, to obtain lower sound levels, without the risk of compressor overheating. MT and MTZ compressors are available in 26 different models with displacement ranging from 30 to 543 cm3/rev. Most compressors exist in two versions:

Standard version.

VE version (oil equalisation + oil sight glass).

The MANEUROP 8-cylinder compressor

With the new generation of 8-cylinder compressors consisting of two 4-cylinder compressors, mounted in parallel in a common hermetic shell, installations will become more simple.

Perfectly adapted for heat pump, refrigeration and air conditioning applications, these compressors are an example of progress in hermetic technology and reliability, representing the future for 20, 25 and 30 hp compressors.

Maneurop Built in Safety Features

The Maneurop Refrigeration Compressor has many excellent design features but two of the need to be noted, However before relying on these features first check with your specific Maneurop Specifications to ensure that are included on your Maneurop Refrigeration Compressor's

Thermal overload

This protection device open circuits the connections between the supply and the windings should some fault occurs that caused the Maneurop Refrigeration compressor to overheat. The Thermal Overload is self resetting and should reset to normal running once the Refrigeration Compressor has cooled down to acceptable levels

High Pressure blow-off

This protection device blows off the delivery refrigeration gas and puts the Refrigeration Compressor into a running OFF load cycle should the delivery pressure exceed a pre-set pressure level

Condenser and Refrigeration Tips and Tricks

Transport

For information regarding the supply of these units refer to your terms and conditions. Before use make sure that the unit is in good condition and has not been damaged externally .Installation of Condensing unit and relating equipment must be installed by qualified staff.- The installation of the condensing unit is subjected to the norms and technical standards for refrigeration and electrical connections in your respective country.

The application limits for low back and high back pressure as defined by TECUMSEH . must be respected.

INSTALLATION

Important: do not handle the condensing unit by the tubes, but by the bracket provided.

Location

The condensing unit should not block or obstruct thoroughfares, persons, doors or shutters

The surface (wall or ground) supporting the condensing unit must be capable of bearing its weight. Ensure that the condensing unit is installed in a level position.

Keep enough distance between the compressor and any objects in its surroundings in order to ensure good air circulation.

Do not expose the condensing unit to heat or humidity.

Do not use it over the maximum operating pressure.

Avoid corrosive