Had a propane tank today. Supply was flexible copper ran to house underground then converted to black pipe from there on. Can flexible copper be ran underground for propane?
No problem in my area. That’s how mine was until I converted to Natural gas.
The propane supplier usually runs the line from the tank to the house here.
Same thing, the PLBG.Contr. or HVAC Contr. usually runs Black Iron pipe from various appliances to building edge, stubbed out with pressure guage on. The LP supplier locates Tank (usually above ground and within 20’-25’ of foundation and/or connection) and runs copper underground (min.18" below) and makes final connection, fills and test fires lines and appliance(s) before either shutting back down or leave operational, depending on local inspection requirements.