Forum Discussion
Old-Biscuit
Jul 05, 2015Explorer III
OPD......Overfill Protection Device. Basically an internal float that shuts off at 80% liquid level. Device is designed to help prevent overfilling of a propane cylinder
Doesn't stop flow of propane out of cylinder only into cylinder when filling.
ACME nut...large green nut on hose.
*Has a 'nipple' that opens a spring activated shutoff valve inside propane cylinder service valve. Propane will not flow out of cylinder unless hose is attached and nipple is holding spring loaded valve open.
*Has a 'thermal bushing' that will melt if temps exceed 240*F. When it melts the 'nipple' slips back about 1/4" allowing spring activated valve in cylinder service valve to close.
*Has a flow limiting device...excess flow. Basically a ball bearing that moves towards back of ACME nut when you open cylinder service valve. Then will move back to center position when downstream system is pressurized.
This excess flow device will close off if hose breaks...leak occurs.
(But if you open cylinder service valve quickly.....ball bearing may not return to center position allowing flow. Just close service valve...wait 30 seconds. Open valve slowly)
2 stage LP Regulator
1st stage reduces cylinder pressure to 15 PSI. 2nd stage reduces to 0.4 PSI.
Regulators are typically rated to flow 200,000 PLUS btu per hour...otherwise they wouldn't be able to supply enough propane flow for all propane appliances.
100% of propane devices should be in service to set regulator for 11"WC (can be done with at least 50%)
No flow from cylinder....
ACME nut not on properly...nipple isn't opening the cylinder service valve spring activated shutoff
OR
Opened cylinder service valve to quickly and tripped the flow device inside ACME nut.
Doesn't stop flow of propane out of cylinder only into cylinder when filling.
ACME nut...large green nut on hose.
*Has a 'nipple' that opens a spring activated shutoff valve inside propane cylinder service valve. Propane will not flow out of cylinder unless hose is attached and nipple is holding spring loaded valve open.
*Has a 'thermal bushing' that will melt if temps exceed 240*F. When it melts the 'nipple' slips back about 1/4" allowing spring activated valve in cylinder service valve to close.
*Has a flow limiting device...excess flow. Basically a ball bearing that moves towards back of ACME nut when you open cylinder service valve. Then will move back to center position when downstream system is pressurized.
This excess flow device will close off if hose breaks...leak occurs.
(But if you open cylinder service valve quickly.....ball bearing may not return to center position allowing flow. Just close service valve...wait 30 seconds. Open valve slowly)
2 stage LP Regulator
1st stage reduces cylinder pressure to 15 PSI. 2nd stage reduces to 0.4 PSI.
Regulators are typically rated to flow 200,000 PLUS btu per hour...otherwise they wouldn't be able to supply enough propane flow for all propane appliances.
100% of propane devices should be in service to set regulator for 11"WC (can be done with at least 50%)
No flow from cylinder....
ACME nut not on properly...nipple isn't opening the cylinder service valve spring activated shutoff
OR
Opened cylinder service valve to quickly and tripped the flow device inside ACME nut.
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