A high efficiency Nordyne furnace is installed in an attic. It is drawing combustion air from inside the attic as there is only one PVC pipe on the roof. Does this warrant repair by HVAC tech?
Not necessarily .
Should have both on the roof due to pressure differentials however.
They could have used a concentric vent and should have if to lazy to add another vent.
it is perfectly fine to get combustion air from the attic as long as there is a PVC elbow and screen installed on the combustion air inlet.
Do you have an image of the exhaust configuration at the penetration of the air handler cabinet?
Here are some pics
Is there a drain pan ?
I see a condensation tube, but where does it go?
Unrelated ,it sure is easy to see the exhaust is on the north end of the roof, and those birds must be everywhere.
Still would have been nice to run a supply through the roof. Goose neck PVC looks cool. 
No drain pan, already called that out, thanks 
condensate line goes into a DWV.
Thanks Mark…but I was curious and wanted to view the exhaust/combustion air penetration area at the right side of the cabinet.
Hey Mark - the units have to be installed to meet code requirements AND manufactures installation requirements. I would check with the manufacturer to see if this was an allowed installation. See http://www.nordyne.com/web/ResLand.aspx for their site.
Hey Mark,
Like others have mentioned, I would totally check with the manu to see if this type of installation was even allowed for their site?
Also-- would you be able to share some pics of the exhaust/combustion air penetration zone on it?
Thanks,
Vanessa Moss
I know its an older thread but always down to help when we can!