Service & Maintenance / Extra Edition

Troubleshooting Challenge: A Soda Vending Machine That's Not Performing Properly ... Sometimes

September 7, 2009
/ Print / Reprints /
/ Text Size+
Figure 1. (Click on the image for an enlarged view.)

This month’s problem piece of equipment is a soda vending machine that has basically the same refrigeration system as a standard household refrigerator in which a standard capillary tube metering device is used to feed the evaporator. The other “refrigerator” similarities are a fan-cooled condenser and a forced-air evaporator. Figure 1 shows you an illustration of the evaporator section of the system (top) and the condenser section located in the lower part of the cabinet.

The complaint from the customer, who has positioned the unit outside their small motel, is that while the soda seems to be properly cooled during the middle of the day, there are times when the product is warmer than desired. Temperatures during the day are in the mid 70s, while the temperature later in the day drops to the low 40s. When you make your initial stop early in the afternoon, you note that the unit seems to be operating normally with both the evaporator and condenser fan motor running normally. And, when you check the wiring diagram, you note the condenser fan wiring shown in the partial diagram in Figure 2.

Figure 2.

Since your initial check of the equipment shows no problems, you decide to schedule a second trip back to further evaluate the situation after the outside temperature has dropped. When you return during the low-ambient situation, you note that both the evaporator and condenser fan motor are again operating normally.

Your troubleshooting question: What is the next step you need to take to resolve the cooling problem with this equipment?

Compare your answer with ours by clicking here.

Publication date: 09/07/2009

Did you enjoy this article? Click here to subscribe to The NEWS Magazine

Recent Articles by Jim Johnson

You must login or register in order to post a comment.



Image Galleries

2014 Energy Efficiency Forum

Highlights from the 25th annual Energy Efficiency Forum in Washington, D.C.


NEWSMakers: Jason Vogelbaugh

Jason Vogelbaugh of Alpha Controls drops in to the NEWSMakers podcast to discuss his role with the company, the InsideIQ Building Automation Alliance, and current energy-efficiency projects being worked on. Posted on Sept. 26.

More Podcasts


NEWS 09-29-14 cover

2014 September 29

Check out the weekly edition of The NEWS today!

Table Of Contents Subscribe


DOE has denied AHRI’s petition for reconsideration of walk-in standards. Is it getting harder to reach consensus on efficiency standards?
View Results Poll Archive


2014 National Plumbing & HVAC Estimator

Every plumbing and HVAC estimator can use the cost estimates in this practical manual!

More Products

Clear Seas Research


Clear Seas ResearchWith access to over one million professionals and more than 60 industry-specific publications, Clear Seas Research offers relevant insights from those who know your industry best. Let us customize a market research solution that exceeds your marketing goals.


Magazine image
Register today for complete access to Get full access to the latest features, Extra Edition, and more.


facebook icontwitter iconyoutube iconLinkedIn i con