Vintage Drink Machine Repair and Restoration

What to do if your machine is freezing up

“My drinks are not getting cold and when I open up the machine the evaporator is a block of frost or ice!”

There are a few possible reasons for this.  75% of the time it is one of the reasons below.   It’s important that you defrost the machine completely before turning it back on.  

Lets look at these one at a time. 

#1 Warm Air Leak: 

If the machine’s main door or bottle door is not sealed well, the fan can pull warm air into the machine.  Even a small leak makes a difference.  You may not notice it until it’s hot outside.   As a result, the air inside never gets cold enough for the thermostat to turn off the compressor. 

And over the course of hours of constant running, ice crystals build up.  Once the ice starts to build, it inhibits the airflow.   Without good airflow, more ice accumulates.  Sometimes the fan hitting the ice will make a noise, or sometimes the ice gets so thick that the fan can not turn.   And then more ice builds without airflow.  And it will never get to temperature.   What do you do?  The solution would be to check all the seals for gaps. 

#2 Too Hot Outside:   

A similar issue when the outside temperature around the machine is too high, or the machine is in direct heat or direct sun.  In this case, it is not hot air leaking in but rather the hot air outside is too much for the insulation in the walls.   Then the same cycle described above takes place.  In this case, you may have to move the machine into a garage or put it in the shade. 

#3 Defective Thermostat:  

The thermostat has one job, turn the compressor off when the temp gets down to around 38 degrees inside, and then turn it back on when the temperature gets up to around 44 degrees.   (These temperatures can vary based on what you have it set to).    

If the thermostat is stuck or defective, it may not turn off the compressor when it should.  And then it’s the same cycle as above:  Ice crystals build, resulting in air not circulating, and the temperature can’t get below 40, and it ices up more and more until no air is moving over the coils.   

Important: If you install the thermostat upside down, it will run until it ices up.   Be sure it is installed correctly, see the image below. 

You can get a new thermostat for systems we use here on Amazon.  or eBay.  The product number is K50-P1125.  Unplug your machine, and install it just as it was.  We can help if needed. 

#4  Evaporator Fan.   Your cooling system has 2 fans.  The one in the drink area is the evaporator fan.   It runs all the time, it never shuts off.   (the other fan  in next to the compressor and it cycles on and off).  If the evaporator fan is not working or jammed, then it not move air.   This will cause an ice issue.  Be sure this fan is working and moving air freely, usually up again the back wall on most machines.  Just be careful to not get your fingers near the fan blades. 

If none of the above solves your issue, you may need to call a refrigeration person or contact our supplier ( for additional advice.    

Lastly, we highly recommend putting your machine on a timer, so it has a daily defrost cycle.