Thursday, March 3, 2011

Refrigeration Repair Guide

Refrigerators are one of the appliances we can't live with out. Imagine you have so many left over food after having dinner or when you go grocery where will you keep your food? there's more than a thousand  reasons why refrigerators are so important in our homes and other business.
This Article is a simple guide for us on how to basically identify or fix problems regarding our refrigerators.
this is just a very easy step by step procedure on how to identify its problems.
all you need is a little time and patience.but first we must identify what and how Refrigerators works .

                                   This Figure Shows the parts of a typical frost free refrigerator. other parts may not 
                                                                                available if your ref. isn't frost free 

 Refrigerators are classified in two categories mechanical and electrical.
the mechanical part of the refrigerator is the one responsible of its cooling mechanism (technician called it " cooling system") consist of condenser coil, evaporator coil, motor compressor. ill explain later on how to troubleshoot in this part.
The electrical part of the refrigerator is the one controlling temperature and maintaining its own mechanical lifespan.Yes refrigeration has its features in protecting it self from overheating and power fluctuation.So don't worry plugging your refrigerator 24/7 thanks for its temperature controlling features (thermostat ) it automatically shut off the motor compressor  when it reaches a certain temperature unless of course if it bad ill explain in the later part how to identify bad thermostat. electrical part of a refrigerator are consist  of capacitor ,relay,overload,switches, thermostat ,evaporator fans ,condenser fans, timer etc.but not all refrigerators has this stuff other refrigerators don't have evaporator fans,timer and condenser fans meaning the less the electrical features the easy it is to troubleshoot .So before you call your nearest handyman or Refrigerator repair shop ("that would cost you a lot on your pocket"). you must first read this guide. maybe this could help you identify your refrigerator problems and fix it on you own.

To start troubleshooting test make sure you "unplug your refrigerator" this could lead to electrical shock or worst. consider safety is the number 1 priority.

Trouble Shooting Mechanical Parts of a Refrigerator
Before we start lets have a short review in Mechanical part of a Refrigerator. 
the motor compressor of a fridge is the one recycling the refrigerant in the system by the way they are two kinds refrigerant in refrigerator R12 and R134-a. you could identify the refrigerant by looking at the back of your compressor.(Note:R134-a are commonly use today R12 has been face-out but there some old model fridge that still uses R12 )



Common Symptoms of a Burned Compressor and How to Fix it!!!
1. If the compressor doesn't start running even you already turn on the thermostat /switch of the fridge.(this is a really tricky part there's a lot of trouble you can consider having this problem.)
  
                                                                         
                                                                                                                 

 Solutions:                              
(Identifying bad capacitor)
This is a common problems for bad capacitors,relay or overload protector of your compressor or worst its the burned compressor it self. Best thing if you have your multi-tester with you to check your capacitor its very easy to identify bad capacitors if it flicks upwards and go down it means its still OK. or you could identify it when you see a leak or some liquid coming from inside the capacitor.other compressor has no capacitor so don't for it if has no capacitor.




 
(Identifying bad relay)
You could identify bad relay. figure above shows how your relay works. but basic thing to check your relay is to shake it continuously if something rattling inside maybe there's something wrong with it. better grab you multi-tester and check it.


 


(Identifying bad overload)
Overload protector are the responsible for protecting your compressor for burning it shutoff your compressor when electric current fluctuate o due to motor heat. in other compressor  uses thermal overload located inside the compressor body so don't be confused if you don't see any overload in your compressor.in identifying bad overload you will need a multi-tester to check for its continuity.


    If you cunduct all three test 1-2-3 and find nothings bad. Your compressor might be Burned. why does compressor burned you'll find in the later part of my article. 
(Note: For burned compressor better contact your Technician to have it replace )

2. If your fridge is grounded  it has electrical charge in its body. it electrify you when ever you are expose to its metal parts. and if there's no response to the compressor.(not vibrating)





Solutions:  
There no remedy for this problem but to replace your compressor.
better call a technician to handle this problem its quite to risky.


3. If the compressor is still running but the evaporator doesn't cool.



Solutions:
We have to consider two cases in identifying this problem. first if the system have a leak there's is no or few refrigerant present in the system not sufficient to cool the evaporator. and the lose compression of the compressor. the compression of the motor is not enough to pump the refrigerant.
 
Checking leaks in your Evaporator and Condenser

                                                 Common refrigerator evaporator for non frost free

Evaporator is the low pressure side of the system it generates coolness in your fridge its usually made of aluminum and that's  why it always prone of getting cut and having leaks.

                                                                   Refrigerator Condenser

Condenser is the high side pressure part of cooling system. witch means when the evaporator is getting cold the condenser is getting hot.

How to find leaks in your evaporator and condenser?
This quite easy but it takes time for you to locate the leaks. All you have to do is get a sponge an a soap wipe the bubbles in every part of your evaporator (inner part) you will determine the leaks because the bubbles will react when it reaches the leak spot.same goes with condenser.

Solution:
When you determine the problem is a leak on your evaporator or condenser its better to call a technician on this one.


Determine and Fix Refrigerator Electrical Problems(for none frost free units) 
Finding electrical problems on your refrigerator is easy. Most electrical problems are due to burned wires and plugs cause by short connection and cut wires due to rats and insects.
Try looking at the back of your fridge check first the wire located at the your compressor see if everything's OK. no cuts no sign of burned wire and check the motor terminal if its tight enough to  avoid lose connection.

The thermostat of a refrigerator is the responsible of shutting off your fridge when it reaches a certain temperature it has the function to turn off /on or turn higher/lower the temperature
so if your fridge doesn't automatically shutoff when your at low temperature settings it means there something wrong about the thermostat. (note:bad thermostat could lead to burn compressor) how to replace bad thermostat?


Solution:
unscrew the thermostat and pull it out on its terminal. (its easy to pull out) replace it with a new one


Determine and Fix Refrigerator Electrical Problems(for frost free units)
Frost free units are a lot more complicated than ordinary refrigerator it has more electrical features.Frost free fridge has certain stuff that a ordinary fridge don't have. thermo disk, evaporator fan and timer are some features of frost free fridge that often to have a problem.


Timers often located in the back of inside your fridge. when the timer resets you could not able to turn on your compressor.

Solution: 
  You'll be needing a screw driver to turn the timer again. just twist sideways wait until  your compressor starts to vibrate again.


When having a Thermo disk problem you'll be experiencing your evaporator blower doesn't blow much. it's because the ice inside the evaporator prevents the blower to cycle it's  intake air.

Solution:
Open the cover o your evaporator (plastic) unscrew and look for a tiny disk attached to your evaporator. cut it out and replace with a new one its important to bring your sample disk when you buy one..

Basic Refrigeration Trouble Shooting  I hope it helps you..