Why are fiber union washers still a thing?

Jells

I'm getting really frustrated that every time I need to service a valve with fiber washer unions it's a bear trying to get it sealed again! I had to crack the seal on a mixing valve union to drain some water from a DWH tank, (the damn vacuum breaker failed like they always do!) and could not get it sealed again without some dope on it. Was nervous about that, but some search showed it's not uncommon.

So why do they still use fiber instead of EPDM or some other elastomeric seal that's more dependable? And what's with the **** vacuum breakers? Some of them are $80 and still either fail to open or fail to seal again. It's the same issue, the ring in the unit gets permanently deformed and fails to seal again.

ChrisJ

Jells said:

I'm getting really frustrated that every time I need to service a valve with fiber washer unions it's a bear trying to get it sealed again! I had to crack the seal on a mixing valve union to drain some water from a DWH tank, (the damn vacuum breaker failed like they always do!) and could not get it sealed again without some dope on it. Was nervous about that, but some search showed it's not uncommon.

So why do they still use fiber instead of EPDM or some other elastomeric seal that's more dependable? And what's with the **** vacuum breakers? Some of them are $80 and still either fail to open or fail to seal again. It's the same issue, the ring in the unit gets permanently deformed and fails to seal again.

I've been asking my self and others this for months and months now.

Why not silicone washers? Caleffi offers both, yet ships the paper ones. I thought I finally got my PRV sealed and yet after months I noticed mineral build up around both connections, so, I guess not.

I keep using the paper ones because I assume if it's sold this way I should be able to make it work. But for some reason I keep failing. I don't know. I've tried soaking them first, I've tried going tighter and tighter, I've tried looser. All surfaces are spotless before I re-assemble and alignment is perfect.

When I have time I'm pulling it apart for like the 6th time and going silicone.

EPDM, Silicone, Neoprene are all excellent materials for this.

hot_rod

stand by we have a solution in the works that is making its way into all the product lines.

pros and cons to all the washer material options

Long Beach Ed

Only one reason, and we all know what it is...

Mad Dog_2

In a pinch use good quality Teflon tape like Blue Monster and make your own washer. Make sure you wrap around EDGE & FACE of union joint. Lots of Megaloc on threads and kill it. Mad Dog

ChrisJ

hot_rod said:

stand by we have a solution in the works that is making its way into all the product lines.

pros and cons to all the washer material options

I suppose that's true.

So how about a metal to metal union?  

Alan (California Radiant) Forbes

So how about a metal to metal union?

Wow, a ground joint union? Now, that's what I call brilliant.

Solid_Fuel_Man

I actually ordered a bunch of the red silicone washers from Caleffi..... 

And I use them on all mixing valves. 

Jells

Solid_Fuel_Man said:

I actually ordered a bunch of the red silicone washers from Caleffi..... 

And I use them on all mixing valves. 

That's what I need to do. Of course I ordered some brand new fiber for 'just in case' when I was ordering a bunch of other stuff, and when I needed them they were nowhere to be found! Grrrr....