How to seal endpoints of grey PVC housing gas line?

[NM_Shooter]

We are building a gas fired fire pit in our back yard.

I'm running CSST flex gas line, and the install book says that if buried it has to be in water tight enclosure.  So I am thinking of running it in 1.5" grey plastic electrical conduit.   

The fire pit end I am stuck trying to figure out the water tight end.  I want to bring the gas up within the pit itself.  I don't want an unsightly conduit on the outside of the pit.  I'm planning on a pit that has roughly a 36" interior diameter.   

The book also shows a picture where it says to seal the ends of the conduit to the CSST with "compound non corrosive to stainless steel"

What might this compound be, and where do I get it?  Can it just be a bunch of 30 year silicone caulk on each end?

In order to protect the CSST from the heat, how long of a black pipe lead in should I use as a transition from the flex to the burner?

Thanks!

[MountainDon]

I'm running CSST flex gas line, and the install book says that if buried it has to be in water tight enclosure.  So I am thinking of running it in 1.5" grey plastic electrical conduit.   

The book also shows a picture where it says to seal the ends of the conduit to the CSST with "compound non corrosive to stainless steel"

What might this compound be

I don't have much in the way of answers.       But don't you just 'love' statements like that "compound non corrosive to stainless steel"  and they leave you hanging...  No idea on what that might be.


On another front though frank I have no working email for you anymore and a crashed (literally) phone leaves me with no numbers to call.  PM me if you can. Don.    Maybe a Quarters lunch is in the future   

[Native_NM]

We are building a gas fired fire pit in our back yard.

I'm running CSST flex gas line, and the install book says that if buried it has to be in water tight enclosure.  So I am thinking of running it in 1.5" grey plastic electrical conduit.   

The fire pit end I am stuck trying to figure out the water tight end.  I want to bring the gas up within the pit itself.  I don't want an unsightly conduit on the outside of the pit.  I'm planning on a pit that has roughly a 36" interior diameter.   

The book also shows a picture where it says to seal the ends of the conduit to the CSST with "compound non corrosive to stainless steel"

What might this compound be, and where do I get it?  Can it just be a bunch of 30 year silicone caulk on each end?

In order to protect the CSST from the heat, how long of a black pipe lead in should I use as a transition from the flex to the burner?

Thanks!

They sell a black, polyurethane sealer at the big-box stores for this.  I have a yellow flex gas line inside schedule 80 pvc to an outbuilding. 

[NM_Shooter]

Ahh!!!  Back to Lowe's I go.  I just buried the pvc tonight, and will be running the gas line soon.  Thanks!