How many elbows are allowed on a TPR drain line. This line had 5 elbows (some 45’s) just within the water heater closet.
I do not see anything in “Code Check Plumbing” about it.
I don’t like the looks of it but, that doesn’t make it wrong.
Others may have better info.
It appears the line might be reduced in size, that is wrong.
I don’t like to see any installation with piping across the front of the appliance, as it generally makes the removal more difficult ( obviously the plastic piping is easily removed ). The fact that they are using either cpvc or pvc as the extension piping from the relief valve is a problem. Neither is rated for the potential discharge of the hot water when the relief is opened. The fittings could soften and the discharge piping could be compromised. The number of 45’s in this case is not a problem that I am aware of.
Gerald Wilcox
House Check Home Inspections
CPVC is exceptable for this purpose. 
A couple of links on CPVC:
http://www.ppfahome.org/cpvc/faqcpvc.html
http://www.plastemart.com/upload/Literature/CPVC_Pipessp.asp
Where does it go after entering the wall?
http://www.nachi.org/waterheaterdischargepipingcoursereleased2007.htm
Water Heater TPR Valve Discharge Piping mini-course. Take it (free and open to all
Thanks Jason, for the documentation. This was always considered poor practice, for the reasons I mentioned by us former plumbers. I see it is allowable and I appreciate the info.
Gerald Wilcox
House Check Home Inspections
Max of 4 90 deg elbows and 30 feet of discharge piping.
reference here as well
http://www.nachi.org/forum/showthread.php?t=8003