potty training problems

I have a 7wk old kitten, so I am not sure if this is in the right forum. But he follows his mother to the litter , only to make a left turn and go behind the hot water tank and furnace to pee...

Its almost impossible to get back there to even clean it, I was thinking maybe a stick, or broom with a rag tied on the end. But now it stinks. So, this is my question, I was gonna use one of those natures miracle products or something, to detur the baby, plus get rid of the odor..
But I dont know how to get it back there, besides either soaking the rag on the broom on wiping it back there, or using a spray...
Does anyone know if its harmful to put it behind a hot water tank and a furnace..

I am soooooooooooooooooooooooo fire paranoid..I was gonna read the labels to make sure they arent flamable when I go to the store..
But Im sure its not gonna say dont put it by a hot water tank...

Any suggestions?

Block off the area behind the hot water heater. Also, block off the hot water heater entirely (burns?).
Are the mum cat and kittens kept in the basement, or is just their litterbox down there?
7wks is pretty young to be totally potty trained yet! Just give him some patience, some more litter boxes with different litter, and keep him away from giant hot things.

I actually live on one floor.. Its in my laundry room, only real place for a litter box..
And its not hot, the tank, etc...
Under the tank there is the blocked off door to the pilot or whatever..

With bunnies, and cats, etc. I have never had a problem..

My main concern was trying to spray something in there because of that pilot..

No, I mean, duck tape cardboard around it so that he can't get behind it. Once you do get it cleaned up, you want to prevent it happening again. Maybe that area is the best according to the kitten, and the second best is the litterbox, and once you block it off he'll go in the box by himself. Maybe not, but at least you'll be able to clean it up.

Yea ok thanks, I will do all of that once i find a way to clean it