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I like the approach of Cengel and Boles in their absolutely wonderful undergrad Thermo book. At Slay the PE this is how we handle this issue because our hate for gc is unparalleled.

Wow.. tough crowd. Hello? Is this thing on? 😀

LOL  I’m a developer of technical content for @Slay the P.E.. Re-writing all the problems so they can be solved using only the handbook has been... an adventure.   Having said that, I’m never acting in an “official” capacity when I’m snarky or when I use profanity and sarcasm 😉 

Typo in one of the radiation heat transfer equations:

When using Q=UAFΔTlm for a "complex" heat exchanger the LMTD is the one as defined for the simple counter-flow tube-in-tube heat exchanger.  The NCEES manual does not specify this. Also, what's the deal with using 2.3 log10(x) instead of ln(x)? I mean, I know it's the same thing, but do they...

The correlation for the Nusselt number for constant wall temperature, laminar, fully developed flow is wrong. As shown in the attachment, they have Nu = 4.66 and it should be Nu = 3.66. I am attaching screenshots from two different heat transfer textbooks to show the correct one. Furthermore...

Actually, that's how I've always seen them. Here are snapshots from the heat transfer book by Cengel and from Incropera. The NCEES manual is wrong though, in the use of Lc for the case of negligible heat transfer at the tip.  

Section 5.2.4, the equation for fin heat transfer rate is not correct. If there is negligible heat transfer from the tip, then you use the actual fin length L, not the corrected length Lc. The corrected length is used when calculating fin heat transfer rate for a tip with convection at the tip...

Section 5.2, units of thermal resistance are wrong. The units they specify in 5.2.1 (which I highlighted in blue here) are actually units of R-value, which is NOT the same as thermal resistance.

Ah, ok. Gotcha.

I'm no expert either, but I agree with you. Screenshot of NCEES manual and of MERM13 for comparison:  MERM13:

Oops. I stand corrected. Thanks, Agreed 1,000%

Yeah, temperature, humidity ratio, and enthalpy of the mixture would be weighted averages of the incoming streams, and the mass flow rates of those streams are the weighing factors. You're right. I was thinking of for example if you have the two input conditions in the psych chart and they ask...

Correct. Version 1.1

So, when mixing two air streams (say, the return and the outside air) you use either: 1) The equations (which the new handbook doesn't have), or 2) A psychrometric chart to use the lever rule technique (which requires a ruler, which you're not allowed to bring to the test) This would be...

...well, its nowhere in the NCEES manual (as far as I can tell) Neither is 4,840xCFMxΔW for latent loads. I guess if you work in HVAC you have these memorized, but these could be time savers for TFS folk who in previous test editions learned about them while studying for the test. Now, they...

Analytical expression to calculate humidity ratio at saturation is wrong: The correct expression, from ASHRAE Handbook of Fundamentals:

The analytical expression to calculate enthalpy of moist air is wrong This is the correct one, from ASHRAE Handbook of Fundamentals

I know. The new NCEES printed practice exams supposedly have some of those AITs but I don't know if they have the "drag & drop" type 😂

Yeah, that's gonna be tough. The ChemE board here is a graveyard of inactivity. The last post is from March of 2019.  However, it is worth it going there and reading the posts as it is mostly people asking about CBT stuff.  A few replies from actual test takers. To understand why there's so...