Annual Water Heater Service

Purpose

Define a repeatable annual service protocol for residential tank water heaters (gas and electric, 30 - 80 gallon) under active service contracts. The goal is doubling effective tank life by managing sediment buildup and anode rod sacrifice - a annual service that prevents a emergency replacement.

Scope

Applies to:

• Standard atmospheric-vented gas water heaters, 30 - 80 gal
• Power-vent gas water heaters of the same capacity range
• Electric tank water heaters, single or dual element
• Hybrid heat-pump water heaters (limited scope - anode + filter only)

Excludes tankless (separate SOP), commercial heaters > 100 gal, and any tank older than 12 years (recommend replacement quote instead).

Responsibilities

• Dispatcher confirms model + access (basement / garage / closet) when booking
• Lead technician executes end-to-end; signs the field report
• Customer witnesses the temperature setting on completion and signs off

Procedure

1. Verify model + manufacture date from the rating plate. Calculate age - over 10 years, present a replacement quote alongside the service.
2. Shut off the cold water supply. For electric, kill power at the breaker; for gas, turn the gas control to "PILOT" or fully off.
3. Connect a garden hose to the drain valve and route to a safe drain point (exterior or floor drain - not a sink).
4. Open the drain valve and a hot tap upstairs to break the vacuum and accelerate draining.
5. After the tank is empty, briefly open the cold supply to stir up sediment, then close. Repeat 2 - 3 times until the drain water runs clear.
6. Close the drain valve, refill the tank with the cold supply, leave a hot tap open to vent air.
7. Inspect / replace the anode rod. Magnesium for soft water; aluminum-zinc for hard water. Replace if more than 50 % of the core wire is exposed.
8. Test the T&P (temperature and pressure relief) valve by lifting the lever briefly. It should discharge water; if it doesn't, replace it.
9. For gas units: vacuum the burner compartment, inspect the flame for sharp blue cones, verify draft on the flue with a smoke pencil.
10. For electric units: test elements with a multimeter (open circuit = burnt out), verify both upper and lower thermostats.
11. Restore power / gas. Set temperature to 120 °F (or customer preference, but document anything > 125 °F).
12. Photograph the rating plate, the anode rod (before disposal), and the T&P discharge pipe.

Acceptance Criteria

• Drain water runs clear at the end of flush
• Anode rod is either passing inspection or has been replaced
• T&P valve closes cleanly after test
• No visible leaks at any connection 10 minutes after refill
• Temperature setting documented on field report; customer signature obtained

References

• IAPMO Uniform Plumbing Code, Chapter 5 (Water Heaters)
• Manufacturer service literature for the specific make/model