Drain several gallons from tank to remove sediment.
Manually check operation of safety valve.  Check for corrosion.
Check all connections - electric, gas and water.  Tighten as necessary.
Check operation and setting of aquastat.  Check hot water temperature with dial thermometer, and set aquastat at minimum value.
Check pilot and burner assembly.  Clean and adjust nozzles for proper flame distribution and quality. 
Check operation of electric ignition device, if applicable.  Check spark gap and adjust if needed. 
Check flue for proper draft, leaks, and corrosion.  Check thermocouple for corrosion or soot.  Clean if required.
If the insulation contains asbestos, follow the asbestos management plan for isolation, notification, work practice and waste disposal.
Clean surrounding area, record results and findings and report any needed repairs or operational adjustments.

Obtain and review manufacturer's instructions.  Follow manufacturer’s instructions or procedures if different to these instructions or procedures.
If the insulation is known or suspected to contain asbestos, check the building's asbestos management plan to see it has been tested for asbestos.  If it is suspect but has not been tested, have it tested.  Manage asbestos in accordance with the plan.

Standard and Phillips head screw drivers-various sizes; Pliers-vise grip (2), slipjoint, needlenose, diagonal; cutting pliers, side cutters; Ball peen hammer; Hack saw and spare blades; 3/8' drive socket set and ratchet; Small set of Allen wrenches; Assorted center punches, drift punches, and steel chisel; 12' measuring tape; Crescent wrenches 4" to 8";  Open and box end wrenches ¼" to ¾"; File; Pipe wrenches to 14"; Small level and square; Pocket knife; Flashlights; Grease guns and oilers; Wire brush; Extension cord and inspection lights; Various cleaning tools - brushes, scrapers, etc; Emery cloth.
Pipe wrenches to 24"; Tubing cutters; Flaring tool; Small acetylene outfit; Packing tool kit and packing; ¾" socket set Crescent wrenches to 14"
Cleaning equipment and materials.
Thermometer
Clamp-on ammeter
Gap gauge (auto ignition)
Safety goggles.
Gloves.