HVAC to Refrigeration

[mechAK47]

Hi, I have been working full time in HVAC for about a year and refrigeration interests me much more. Does anyone have any suggestions in what to study before looking searching for a job?

Thank you very much

[techwizard007]

Yes start with Ice Machines ,then reach ins, get involved with RSES very good place to start.
Regards

[ryan1088]

You've already found your best resource. Get your post count up and go pro, then you can see all the good stuff.

[mechAK47]

Thank you very much techwizard and ryan

I have looked into rses training materials in the past. Are you referring to the R/AC series of text books?

I would very much like to go pro and read the educational forums

[Phase Loss]

Read Heatcraft IOM, then get a job

[Tommy knocker]

A lot of stuff out there to read, IOMs, forums like this, text books, and such. I would hit them all. Experience is the best teacher and no substitute for time. Be patient and persistent. The first lesson is SLOW down. This side is a bit more critical then comfort cooling and gas and go tech crash and burn pretty quick. Learn the difference between symptom and problem and pursue the problem. Fix it and the symptom will likewise be corrected. Throwing charge at low pressure will get you in trouble. Good luck.

[Capz]

You haven't mentioned if you were commercial or residential HVAC. I find electrical knowledge & electrical troubleshooting skills of utmost importance when working in the commercial side of this business & this is especially true in refrigeration. Master your electrical skills. Good Luck

[ryan1088]

You haven't mentioned if you were commercial or residential HVAC. I find electrical knowledge & electrical troubleshooting skills of utmost importance when working in the commercial side of this business & this is especially true in refrigeration. Master your electrical skills. Good Luck

I don't want to discount your statement about electrical knowledge, but I will have to disagree some. It doesn't take a genius to troubleshoot even a good size walk in refrigerator with a pumpdown system.

I'd focus more on the sequences of operation to start with. What happens first and in what order it will happen. Once you know this, you can then evaluate what is missing and go from there.

[mechAK47]

I do mostly light commercial but have done some residential and heavy commercial. We are actually working right now on a few residential apartment buildings with up to 70 apartments in one which we are installing a vrf systems in each apartment. The troubleshooting on these units are probably similiar to refrigetion since there are a lot of solenoid valves.

[Capz]

I don't want to discount your statement about electrical knowledge, but I will have to disagree some. It doesn't take a genius to troubleshoot even a good size walk in refrigerator with a pumpdown system.

What's the purpose of your statement if you aren't discounting it? Sounds as if you are telling this kid he doesn't need to understand electric control circuits.

I'd focus more on the sequences of operation to start with. What happens first and in what order it will happen. Once you know this, you can then evaluate what is missing and go from there.

I certainly agree with this too. But having sound electric understanding is very important in my book. Maybe I think this way cause I have better electric skills & knowledge than the average guy. My first trade for years before learning refrigeration.

[VTP99]

True a walk-in cooler is straight forward. After that it can get pretty perplexing moving on to a freezer. If one does not have good electrical skills then he/she best be looking for the schematic.

[Snapperhead]

I've come across some pretty screwed up wiring before , especially with freezers with heaters and time clocks and defrost delays and points not making good contact and LPS and HPS going bad and Ranco switches , wires melting on the heaters .... oh buddy you will have fun with electrical issues

[VTP99]

I've come across some pretty screwed up wiring before , especially with freezers with heaters and time clocks and defrost delays and points not making good contact and LPS and HPS going bad and Ranco switches , wires melting on the heaters .... oh buddy you will have fun with electrical issues

[ryan1088]

The point that I was trying to make was you not only have to be able to troubleshoot electrically, knowing who controls what is just as important.

Example:
You walk up and compressor isn't running. Start checking your safety circuit and LPS is open. We all know where to go from there. Question is, if you didn't know that your next stop should be the tsat or the llsv, what benefit would more electrical theory/practical experience would help you?

[VTP99]

Yes, sequence of operation plays as equal a roll in the troubleshooting process. At least it sure does speed things up. If one starts at the end and then ends up at the beginning only to fine that the power is off. That sure is a waste of time.

[Capz]

I never accurately tracked, but I'd say electrical issues (including motors) are 50% or greater of the issues I see. In fact, hooking up my refrigeration gauges is the last thing I do. I'll use my Fluke 52 or my Fluke 116 much sooner.

[Tommy knocker]

Troubleshooting is troubleshooting. It doesn't matter what percentage of problems are electrical, mechanical, refrigeration, or dirt. You better be compatent in all phases. All are equally important because every call is different. If its an electrical problem being an ace mechanical tech doesn't help. If its a ref problem an electrician will be screwed. Etc etc etc.

[Eadam1985]

I was recently in your position, but i got lucky and was able to learn by experience with my company we got a ton of refer accounts all at once. From my experience i found reading in your hvac book from school helpes a little bit well to get to know the sequence of operations of each different application, and talk to pple from this website helped me out alot!

[SeanH]

I would have to agree with Ryan and capz as well. Sequence of operations and elec knowledge is crucial. How are you supposed to troubleshoot something if you don't know what it's supposed to be doing? I'm a CSR for Manitowoc and in my opinion you might as well memorize the sequence of operations before you even break out the 6 n 1. Also, you MUST be knowledgeable in different Freons and their pressures. Most all refrigeration equipment is critically charged, especially ice machines. Good luck my friend, and be prepared to never go out to eat again. You will see.

[timebuilder]

I would have to agree with Ryan and capz as well. Sequence of operations and elec knowledge is crucial. How are you supposed to troubleshoot something if you don't know what it's supposed to be doing? I'm a CSR for Manitowoc and in my opinion you might as well memorize the sequence of operations before you even break out the 6 n 1. Also, you MUST be knowledgeable in different Freons and their pressures. Most all refrigeration equipment is critically charged, especially ice machines. Good luck my friend, and be prepared to never go out to eat again. You will see.

I know what you mean!

When I cleaned my first ice machine, I became fearful of placing any commercially produced ice in my mouth, LOL!!!

I don't even want to eat in any restaurant where the lowest price item is less than $20!!!!!

Let me make a list for the OP:

1) Learn all about electricity. Electronics is a great way to begin, as you can buy one of those "200 electrical experiment lab" gadgets at the electronics parts store (you know, the one that sells cell phones now?) or you can search online and find a GREAT deal. Nothing will make a wiring diagram on a walk-in look simpler than being able to understand a Darlington transistor setup.

2) Everything has a sequence of operation. Find out what makes things work.

3) Learn about how refrigeration compressors operate. A typical reach-in will have a small hermetic compressor with some sort of starting and overload components. Learn the difference between a current relay setup and a potential relay setup, and how they are wired to an overload and the three compressor terminals.

4) Dick Wirz has an excellent book on transitioning from HVAC to refrigeration.

http://www.amazon.com/Dick-Wirz/e/B001K8RLVW

5) Perhaps the most important change in thinking is to start looking at temperatures instead of pressures. When you work only with comfort cooling, especially commercial where many rooftops are still a decade away from being replaced by a 410A unit, you get used to looking at the gauges and thinking about pressures. Then, when you look at a different refrigerant system, you are lost. Temps will always be similar in a similar application, such as comfort cooling, medium temp boxes, low temp boxes, etc.

Refrigeration is far more challenging, because it is more unforgiving, forcing you to raise your game. A HO may be satisfied if their house is cool, but food that is not cold or frozen will make your phone ring.