Those are the best kind of fixes!
For the HWT, put the plug in, make sure the bypass valves are set for normal use, fill it with water and make sure all the air is out, check that your propane is on and flip the switch. It should work fine.
If the propane has been off for awhile it will take a bit for it to bleed the air out and fill the lines. I usually light a burner on the stove first to get propane through all the lines.
There is a great diagram in the post below on how to set the bypass valves correctly.