The T&P drain line has a slight downfall towards the valve, but the position of the T&P valve is higher than the point of exit in the wall and has about a 2" drop of copper pipe coming out of the T&P, therefore NO WATER could be resting on the T&P valve! Should this still have failed inspection?

YES, it should fail

the discharge line must be pitched CONTINUOUSLY downwards away from the T&PRV

NO water should 'lay in the pipe' - NONE

(dead level for the horizontal sections is the MINIMUM 'pitch')


Remember: code is the MINIMUM - there is NO give in the code

You may, however, exceed the code requirements to ensure good practice

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"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

Yes, a trap is a trap and the T&P could leak water thru the valve for some time before you became aware of it and render the valve inoperable.

quote... "there is NO give in the code"...
there is plenty of give in the code.
code may be modified at the descretion of the local authority.
yeah, no inspector is going to allow you to do something dangerous but slight 'adjustments' are done all the time.

as the code is the MINIMUM requirements for human occupation there 'should' not be any 'give'


IMO

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"Measure Twice & Cut Once" - Retired U.A. Local 1 & 638

YES. The code is that it MUST drain continuously downhill. If the outlet is below the T&P valve, there is no reason for it to go uphill. All you have to do is rotate the T&P valve and then pipe it properly.

That is not a consideration, because once the "Trap" is full the leakage will be apparent.