Just completed the install of a new gas H2O heater. Heat traps left in place, dielectric nipples installed, there were no dust covers on the inlet and outlet ports to remove, gas service lines check, water supply inlet and outlet (hot) are clean w/ new gaskets, tank filled, No leaks, burner works- water tank heats nicely, water flows from the tp relief valve and from the drain port. Problem is, little to no pressure in the hot water lines.
I have attempted to bleed air from the lines, with little success. COld water taps open and flow fine; once the hot water taps are open the pressure drops. When cold taps are turned off, hot water taps show little or no pressure.
I believe this is a case of air trapped in the lines- how do I effectively remove air from the lines. I also heard what sounds like water hammer while attempting to bleed the air from the piping.

I believe this is a case of air trapped in the lines- how do I effectively remove air from the lines. I also heard what sounds like water hammer while attempting to bleed the air from the piping.

I disagree. If,(and this is a iffy IF) there were really air trapped in the hot water line simply opening up the last hot water faucet on the line would bleed off any air in the line. No my friend, this sounds like you've disturbed mineral buildup in your pipe walls and now you have sucked them up into the inlet ports of the cartridges of the faucets affected where it's now blocking the flow of hot water. The solution would be to shut the water off to the nearest hot water faucet affected, open it up and check and clean the cartridge ports. Before you button up turn the hot water back on for a minute to flush out the branch and supply lines. You should have a full stream of hot water. If no click on back. If you do then move on to the next faucet affected and do the same thing until the lines and faucets are clear.We'll address the water hammer after you clear the lines. Good luck, Tom

When turning water back on after repairs it is best

To not turn on full pressure until lines are bled...

Just crack the shutoff and go to each faucet and

Complete job, before applying full pressure...