New guy here with a ?

[coolmiser]

I have to admit I have been stalking this site for some time while studying for my service tech license , I have already gotten my universal EPA & have had 10 years experiance installing & servicing residential systems .

The question in my study guide that I can't seem to wrap my head around is " A thermostatic expansion valve was factory set at 0* superheat . How much was the feild setting ? = 4-8* " how is this answer determined ? :confused:

[phbsales]

What application for the TXV? Comfort cooling? Refrigeration? What are the manufacturers SH/SC requirements for that particular unit?

These questions need to be answered first before you can determine what the field setting should be.

[coolmiser]

Thats it to the question , straight out of the Refrigeration license exams book by arco (petersons), no elaberation to conditions or applications

[Green Mountain]

Unless they are referring to the difference of the actual satuated vapor and the temp taken at the line. ??

It is not a straight forward question. I agree it would help to know the application of the valve.

[rogerk]

I wouldnt worry too much about it. 99% of the study guides I wasted my money on had questions in them that were not even remotely close to what was actually on the exams.

[DavyB]

I have to admit I have been stalking this site for some time while studying for my service tech license , I have already gotten my universal EPA & have had 10 years experiance installing & servicing residential systems .

The question in my study guide that I can't seem to wrap my head around is " A thermostatic expansion valve was factory set at 0* superheat . How much was the feild setting ? = 4-8* " how is this answer determined ? :confused:

You have to "field-set" a txv?:eek: I would have to guess at whatever the unit equipment mMfg. recommends? (if that is an option, of course.)

[supertek65]

i think wat you are looking for is

you need 12 degrees superheat

evaporator sh

co comebody opened the tev counterclockwise 6 turns

2 degrees per turn

to make it 12 degrees you must close it or turn it in clockwise 6 turnse

frank

[coolmiser]

I have read this chapter on metering devices a few times & see no reference in how to come up with thye correct answer .

another question from the book is " A Thermastatic expansion valve with a static setting of 7* superheat would have a field setting of ?
answer > 11* F superheat.

I just don't see what they are doing to get these answers .

[vmc1161]

I have read this chapter on metering devices a few times & see no reference in how to come up with thye correct answer .

another question from the book is " A Thermastatic expansion valve with a static setting of 7* superheat would have a field setting of ?
answer > 11* F superheat.

I just don't see what they are doing to get these answers .

I don't have your book, but maybe look for something like this ...

Static Superheat relates only to the TXV and is difined as the superheat below which the valve remains closed and above which the the valve starts to open. The 11* is up to you to figure out ... good luck, hope this helps and does not lead you down the wrong path.


.

[Texas-Tech]

most residential valves I've run across are not field adjustable. Unlike refrigeration applications or larger package units.