Connect CGA-320 CO2 cylinder valve to G5/8 regulator inlet
How to join 0.825"-14 NGO RH and G5/8 (BSP parallel), and what stops it leaking.
Not a direct fit. Joining CGA-320 CO2 cylinder valve to G5/8 regulator inlet needs a CGA-320 to G5/8 regulator inlet adapter.
The two ends
- End A
- CGA-320 CO2 cylinder valve (0.825"-14 NGO RH)
- End B
- G5/8 regulator inlet (G5/8 (BSP parallel))
- A seals on
- nylon or fibre washer inside the nut against the valve outlet
- B seals on
- flat washer on the face of the inlet
- Part needed
- CGA-320 to G5/8 regulator inlet adapter
The part to buy
Some regulators have a G5/8 parallel inlet rather than an integral CGA-320 nut. A CGA-320 to G5/8 adapter screws that regulator onto a North American CO2 cylinder: the CGA-320 nut goes on the tank, the G5/8 face seals to the regulator on a washer.
Two different sealing rules on one adapter. The CGA-320 nut seals on its captive washer against the tank; the G5/8 end seals on a flat washer against the regulator. Neither wants tape. A weep here is almost always a tired washer, not a loose nut.
Related connections
Sources: CGA-320 CO2 cylinder valve outlet thread reference (0.825in-14 NGO, RH) · CO2Art guide to cylinder connections (CGA320, W21.8, DIN477, BS341, G5/8, TR21-4) · ISO 228-1 (G / BSP parallel pipe threads)