Both boilers drip legs where in contact with the floor, I could not see how you couls service the pipe without taking apart, way up stream.
See a lot of those drip legs with caps setting on the floor to help support the larger gas lines but that was legal way back when around here.
I think as I recall, all gas pipes need to be 12" above the floor with the current code.
Right Jeff?
I’m getting to old to remember all that stuff and too lazy to look it up. 
It looks like that floor has been re-poured on top of the original floor, covering up the cap.
Bad deal IMHO, mainly because the pipe is soo thin at the threads it wouldn’t take a lot of time to rust through.
3-1/2" per IRC, 6" per UPC
so gas pipes that are run underneath the furnace and are about 1-2 inches above the floor are no good? Also, what is the minimum length the drip leg should be? 3 inches? saw one today that was no more than an inch.
also, if you don’t see a drip leg on either the water heater or furnace, is there a particular spot to check to see if there is a main drip leg as it enters the house for all the appliances or should each appliance have its own drip leg and one drip leg for the house should be noted as wrong.