It is possible to convert a tank to the new valve but you will need to have the tank re certified before it can be refilled.
New vs old propane tank valve.
This prevents more propane from being added to the tank.
The opd valve incorporates a safety feature that prevents overfilling the cylinder.
All propane gas cylinders under 40 lbs require an opd or an overfill protection device.
It is not true that you can have an old style tank refilled.
A plug is screwed into the propane valve for transporting or storing the tank.
When the level of liquid propane reaches the limit the float rises and the valve closes.
Since april 2002 propane tanks without opd valves cannot be refilled.
With out the overfill protection they will not or should not fill it.
Pol valves are the oldest standard for propane tank connections and newer types are more widely used.
This is an important safety measure.
Older propane cylinders won t have one but that needn t mean replacing the entire tank at high cost.
The real difference is that the new tank valves have both a tipover protector and an overfill protector.
It is true that the new valves have both male and female threads.
The next refinement of propane tank connections comes in the acme valve.
Tanks with the older acme valves are legal to use and transport but only those with opd valves can be legally filled.
Pol valves allow the release of gas without anything connected to it.
Dozyant universal fit pol propane tank adapter with gauge converts pol lp tank service valve to qcc1 type 1 old to new connection type propane tank gauge 4 5 out of 5 stars 524 15 99 15.