Where to find 1 1/2" heater to PVC threaded unions?

[zimm]

My Teledyne heater has 1.5" metal pipes with a flange, then there's an o-ring/union on the PVC side that screws together. I need to replace both of them. What am I looking for and where can I buy them?

Here's a pic of my SWG, but you can see the black collar on the metal pipe coming down from the heater. I need the PVC joints and o-rings....

 

[257WbyMag]

My best bet would be a plumbing supply place. I don't think that Home Depot or the more common places would have the black pipe with a flange. You could check though. Some seem to have better selections than others.

 

[zimm]

I found these and ordered a pair. I hope they work. They have split nuts if the original ones don't fit.
http://www.magicplastics.com/vnf_uniona.htm
0611-15