7 Subcool & Superheat Problem Scenarios

[DTLarca]

I'm not going to help anyone with any clues.

There are a few of our employees and subbies out there who know the answers - please don't pass clues.

What is the problem with the system in each of the subcool and superheat combination scenarios?

The scenarios are based on Gary Lloyd's eliminative principles.

[NoNickName]

Probably too simplistic... but interesting for developing diagnosing skill

[nike123]

First, is this capilary or TXV or electronic expansion valve controled sistem?

[TRASH101]

Secondly does it have Head Pressure Control?

[DTLarca]

You're asking for too many clues :)

[DTLarca]

NNN - this is probably too advanced for you.

[nike123]

You're asking for too many clues :)

Same scenario with different expansion device gives different answer. Without knowing that, I suppose, it cannot be correctly answered.

[NoNickName]

NNN - this is probably too advanced for you.

Aahahaha... as far as I'm concerned the 7 scenarios do not show any problem. All of the combinations are perfectly suitable for any system, considering that "norm" SC and SH are generally not published, and a difference of few K may well be the tolerance of the field instrumentation of different engineers.
But if you are reaching the orgasm with this simplistic tests, go ahead, and make your day.

[DTLarca]

In other words too complicated for you :)

[DTLarca]

Okay Nike - good question - so, just one clue: only TEV and Cap-Tube relevant here.

[nike123]

Okay Nike - good question - so, just one clue: only TEV and Cap-Tube relevant here.

That is not clue at all.
TXV and capillary tube system with different superheat and subcooling values could be perfectly OK.
Make up your mind and tell us what is expansion device used in this scenarios.

I like these scenarios (http://www.refrigeration-engineer.com/forums/showthread.php?t=17214&highlight=scenarios). Pretty much less misleading.

[DTLarca]

Both TEV and cap-tube expansion devices are relevent to the scenarios - a skilled subcool and superheat troubleshooter will look at the numbers given and know which readings are from a cap-tube circuit and which are from TEV circuit.

[NoNickName]

In other words too complicated for you :)

In other words, let me translate it for you, the 7 scenarios do not show any problem in themselves.
Publishing a list of SH and SC out of context just constitutes poor teaching practice.

For your knowledge, I am a member of Ashrae technical commitee TC9.9 and writer for the most popular HVAC teaching and formation magazine in my country.

Please don't take your time explaining who you are, because I don't give a f--k. You are the first proud member of my ignore list, and that's enough for me.

[DTLarca]

In other words, let me translate it for you, the 7 scenarios do not show any problem in themselves.
Publishing a list of SH and SC out of context just constitutes poor teaching practice.

There is a very clearly defined context. It need be no more distinct.


The scenarios are based on Gary Lloyds Illiminative Principles.
The first row of numbers indicate the same system when all is good.
Sometimes the system has a cap-tube and sometimes a TEV.

For your knowledge, I am a member of Ashrae technical commitee TC9.9 and writer for the most popular HVAC teaching and formation magazine in my country.

I don't doubt that - I think you do have some good knowledge from what I've read. But you are also quite naive. I'd be happy to show you all the technical errors or vagaries in your articles :)

[glenn1340]

There`s only one way to settle this.
In the words of Harry Hill "FIGHT!!!!!!!"

[mikeref]

Both TEV and cap-tube expansion devices are relevent to the scenarios - a skilled subcool and superheat troubleshooter will look at the numbers given and know which readings are from a cap-tube circuit and which are from TEV circuit.
Well, lets see. For #3, 2k sub and 10k super...capillary system working hard, high condenser and evap loads.... OR, tev system with high evap load. Either way,not enough info for correct assessment. To be bold, 2k sub could represent undercharged and shot condenser with 2 of 3 fans dead on a cool day:confused:. Mike.