help

[kenny3412]

hi guys worked in mainly residential for the good part of 15yrs, started with a new company and they do quite a bit of commercial.r there any good books or guides on commercial equipment ,i can more or less figure it out but id like to learn more. any help wuld be appreciated

[Six]

Hmmm..I've worked commercial my entire career and I cant think of a book per se.

Commercial is so varied. It could be anything from a package unit to a chiller to crawling up in a false ceiling to trouble shoot pneumatic control issues.

It really depends on exactly what type of commercial you're doing. If you walk up to a chiller with only resi experience a book isn't going to help you.

A better option is to learn from someine with experience.

[barbar]

I would suggest you get yourself a good PT chart (s) (for the different refrigerants), understand what you are trying cool. Then there is little difference.

[kenny3412]

im talking more controls i know there mostly the same but sequences and somne controls r different. al,so anything on economizers setuo and troubleshooting would b great

[Six]

Controls of what ? It is NOT remotely the same as what's typical in residential.

If you stick to small package units well then that qualifies more as light commercial.

I have yet to see a home with a pnuematic reverse acting two input reciever controller for the purpose of controlling static on a 40 ton AHU by way of a set of variable guide vanes actuated by a huge pnuematic actuator with a pilot positioner on it.

Also the loads on commercial buildings are not the same as a residential application. Make up air requirements for kitchens, dr offices and spaces that are crowded during working hours like waiting rooms and conference rooms and even theatres.

Any one tells you its the same doesn't know what they're talking about.

[barbar]

im talking more controls i know there mostly the same but sequences and somne controls r different. al,so anything on economizers setuo and troubleshooting would b great

Your application, determines control methods (understand what/why you are cooling)
It is funny you should mention economizers, as depending upon what part of the industry you are working in these can have 2 different complete meanings. (and some times even on the same site)
1; The use of ambient air, to produce cooling. (for example, if the outside air has less energy than return air, then it is more efficient to chill, the outside air and dump the return air)
2; Screw, scroll, rotary vane and multistage compression compressors, can using a side port, aid in refrigeration performance "normally (but not limited to) liquid sub cooling)

If you have a good understanding of refrigeration principles and how energy flows, then you will understanding why the various control are required and what drives them.

The rest/specific is just experience and research.

No one knows all, so do not be afraid to use tech support from your various equipment suppliers/manufactures/and work colleagues!!!!!

I presume they have employed you, knowing your history, so any good boss, will expect you to be on learning curve.

Good luck

[Cooked]

..........I have yet to see a home with a pnuematic reverse acting two input reciever controller for the purpose of controlling static on a 40 ton AHU by way of a set of variable guide vanes actuated by a huge pnuematic actuator with a pilot positioner on it.................

Aw c'mon. they have that crap in window units now.

[Bklyntek]

Every company has particular quantity of machines, that they are Comfortable servicing.
Then get the IOM's for that unit and read it over and over, most important is sequence of operation. Then break down the schematic drawing into their related parts, "on a call for cooling: controller energizes this first" and then at this point/pressure:this proves operation, and then etc;etc;etc. Unit shutdown is in reverse order, i can't lie it will take some time to learn, that's due to all the variety of equipment out there in the market. Keep it up, I've been doing commercial/industri for over 20 years, don't regret it one bit. There's so much to learn, just makes my day,to be out there.