Troubleshooting

• Freezer section still works but fridge won't stay cold
• Your refrigerator is losing pressure and is starting to fail. 

•  If you smell ammonia your cooling unit has failed.  At that point, your cooling unit will need to be replaced. A good thing to keep in mind is that ammonia is extremely corrosive to copper.  There are several parts of an RV fridge that are copper and if you wait too long they will need to be replaced as well.  It will also corrode your shelving. So it is important to keep the refrigerator doors open when you are storing your RV.  Most people don't know that RV Refrigerators can fail whether they are running or not.  If it leaks ammonia while you are storing it and the ammonia stays in the cabinet the damage can be severe. 

• Check the back of the fridge (through the access panel outside and behind the fridge) and see if there is a yellow/green powder present.  That is a rust inhibitor inside the cooling unit.  If you can see it your cooling unit has failed. 

• If you can hear the fridge running, especially if it's making a gurgling noise, it's likely that your cooling unit is bad.  When the cooling unit is working the noise it makes is barely audible.  You will notice the difference when it's failing, the gurgling noise should get your attention. 

 Simple test procedures that will help you determine whether a new cooling unit is 

needed.  The steps below are easy to follow and could save you money.

 1)  Check for an ammonia smell around the

     cooling unit and inside the refrigerator.

     This could indicate a possible refrigerant

     leak. Check for any deposits of yellow

     powder under the burner (in the back 

     of the refrigerator).  That would indicate

     that the cooling unit has leaked.

2)  Determine if the refrigerator works on one

     heat source but not another by testing it in

     the alternate modes. Do you 

     get better cooling results from gas or vice-versus?

     That would indicate that the problem is NOT in the cooling

     unit.

3)  Make sure the refrigerator is level. Sometimes

     the vehicle is level but the refrigerator is

     not.  Place a level on the bottom of the freezer compartment

     and check side-to-side and front-to-back

     levels.

4)  Carefully check door gaskets for proper

     seal. A leaking gasket can allow enough

     warm air inside the refrigerator to overcome

     most of the cooling being produced.

5)  Check the venting system to insure that

     adequate air flow is provided at the back of

     the refrigerator. Remove any restrictions

     in the vents, such as filters, bird nests in the roof

     vent, or smashed louvers in the wall

     vents. 

A simple test to check a heating element is to

measure the resistance through the element

with an ohmmeter. The correct resistance, in

ohms, can be calculated if the wattage and

voltage ratings are known. (These ratings are

stamped on all Dometic heating elements.)

Use this Formula:

Volts + (Watts + Volts) = Ohms

Example:

Heating element rated 135 Watts at 110 Volts.

110 f (13.5 f 110) or,

110 + 1.23 = 89.4 ohms

The ohm reading should be within 10% of this

figure, or between 80.46 and 98.34 ohms. Use

the lowest setting on the ohmmeter which will

give an accurate reading.

When testing a 12 volt heating element, a

very accurate ohmmeter must be used because

of the very low readings that will be found.

For example, a 200 watt element will have a

reading of .72 ohms (less than 1 ohm).

 A  blockage within the boiler

 tube, caused by too much heat

applied to the burner (oversized orifice

or heating element) or prolonged operation

of the unit when out-of-level or with

restricted ventilation. This type of

blockage consists of hard deposits inside

the boiler pump tube. This condition is

not repairable and the cooling unit must

be replaced.