Water heater flue and radon mitigation pipe in close proximity - fire hazard??

[mbasyro13]

I had a radon mitigation system installed in my house prior to purchase. The other day, while doing some sealing in the attic, I noticed that they have the radon PVC pipe running right next to the water heater flue to get from the basement to the attic. You can see a couple pictures here:

Is it OK to have the radon pipe running next to the water heater flue? I checked with the city, but they claim the code only says to "install per manufacturer's instructions." Elsewhere I have heard there should be 2" of clearance between the flue and anything flammable. Is the PVC pipe considered flammable?

Thanks in advance!

Dave

[Lawrence]

That looks OK to me. I don't know the codes but the flue on a modern heater doesn't get hot enough to damage the PVC. Look at it this way, if it were going to cause a problem it already would have. Use a flashlight and take a close look to see if the pipe has been melted. I'm guessing not but worth a look.

[Edwin Pawlowski]

PVC for use in building must have some fire retarding properties. That does not mean it cannot burn with another source of igniton. I doubt it is going to burn the house down, but get some clearance between them. Contact can eventually meld the PVC if it gets hot enough. Just a wedge to get an inch or so should do the trick.

[Joe]

they're not old ones, best keep watch on the situation.

Joe