# Job Hazard Analysis: Water heater installation

URL: https://hardhatbinder.com/en/jha/plumbing/water-heater-installation
Last updated: 2026-10-23

Remove an existing 40–50 gal residential tank water heater (gas or 240V electric) and install a new one in a garage, basement, or utility closet. Includes shutting off utilities, draining, disconnecting, hauling the old unit, setting the new unit, connecting water, gas, venting, and T&P discharge, then filling and testing.

> A general example for this task. Your JHA should reflect your crew, equipment and site — review it with a competent person before work starts.

## Steps, hazards and controls

### 1. Set up the work area and shut off gas, power, and water.

- **Electric shock from the energized 240V water heater circuit.** (High): Turn off the water heater breaker at the panel, then lock and tag it out.; Test the wires at the heater junction box with a non-contact tester and a voltmeter before touching them.; Only the worker who placed the lock removes it.
- **Gas release from an open or leaking gas valve.** (High): Turn the gas shutoff valve at the heater to OFF (handle across the pipe) and tag it.; If you smell gas before starting, stop, open doors, and shut gas at the meter.; Keep all flames, smoking, and spark sources out of the area.
- **Trips over tools, hoses, and stored items in a tight garage or closet.** (Low): Clear a path from the heater to the door before you start.; Set up a work light if the area is dark.

### 2. Drain the old water heater.

- **Scald burns from hot water at the drain valve and hose.** (High): Shut off the heat source and open a hot water faucet to let the tank cool for at least 1 hour if possible.; Clamp the garden hose to the drain valve and run it to a floor drain or outside, away from people.; Open the drain valve slowly and stand to the side; wear heat-resistant gloves.
- **Slips on wet floor from leaks and sediment.** (Medium): Put a drain pan or tarp and towels under the valve connections.; Mop up water right away.

### 3. Disconnect and remove the old water heater.

- **Gas release from the disconnected gas line.** (High): Confirm the gas valve is closed, then cap or plug the open line right after disconnecting.; Check the cap with soapy water or a gas detector.
- **Back and hand injuries lifting a 100+ lb tank, especially on stairs.** (Medium): Make sure the tank is fully drained before moving it.; Use an appliance hand truck with a strap; use two workers on stairs.; Lift with your legs and keep the load close; do not twist.
- **Cuts from sharp vent pipe, cut copper, and sheet metal edges.** (Medium): Use a tubing cutter instead of a hacksaw on copper and ream the ends.; Wear cut-resistant gloves when handling vent pipe.

### 4. Set the new heater and connect the water lines.

- **Fire from the propane or MAPP soldering torch near wood framing, drywall, or stored items.** (High): Use press, push-fit, or flexible water connectors instead of soldering when possible.; If you solder, move flammables away and put a heat shield cloth behind the joint.; Keep a charged ABC fire extinguisher within reach and watch the area for 30 minutes after soldering.; Shut the torch valve off when you set it down.
- **Burns from hot copper pipe and fittings.** (Medium): Let joints cool or cool them with a wet rag before touching.; Wear leather gloves while soldering.
- **Skin and eye irritation from flux and fumes.** (Low): Use lead-free solder and read the SDS for the flux.; Open a door or use a fan for ventilation.; Wear safety glasses and wash hands before eating.

### 5. Connect the gas line, vent, and T&P discharge pipe.

- **Gas leak at new fittings or flex connector.** (High): Use a new gas flex connector and thread sealant rated for gas; install a sediment trap.; Leak-test every joint with soapy water or a gas detector. Never use a flame.
- **Carbon monoxide poisoning from a loose or poorly sloped vent.** (High): Slope the vent pipe up toward the flue at least 1/4 in per ft and fasten each joint with 3 sheet metal screws.; Check for draft at the draft hood after startup and use a CO meter.
- **Scalding from a T&P relief valve that discharges toward people.** (Medium): Run the discharge pipe full size, pointing down, to a safe approved location per local code.; Do not cap or put a valve on the discharge pipe.

### 6. Fill the tank, restore gas or power, and test.

- **Electric shock or burned-out elements from powering an empty tank.** (Medium): Fill the tank and run a hot faucet until water flows steady before turning power on.; Close all covers on the junction box and element panels before removing your lock.
- **Flash or flame rollout when lighting the gas burner.** (Medium): Follow the lighting instructions on the heater label step by step.; Keep your face away from the burner opening and confirm there is no gas smell first.
- **Scald risk to the customer from a high temperature setting.** (Low): Set the thermostat to 120°F and tell the customer.

### 7. Clean up and load the old heater for disposal.

- **Strains and pinched fingers loading the old tank into the truck.** (Medium): Use a liftgate or ramp, or two workers to lift.; Strap the tank down in the truck bed.
- **Slips and trips from water, scrap pipe, and packaging.** (Low): Pick up scrap, cardboard, and screws and dry the floor before leaving.

## Required PPE

- Safety glasses — ANSI Z87.1, at all times.
- Heat-resistant or leather gloves — When draining hot water and soldering.
- Cut-resistant gloves — When handling vent pipe, sheet metal, and cut copper.
- Safety-toe boots — Steel or composite toe, slip-resistant soles, when moving tanks.
- Hard hat — On construction sites or where there are overhead hazards.

## Training

- Lockout/tagout of the 240V circuit and gas valve.
- Gas leak testing and safe lighting of gas appliances; hold any plumbing or gas license your state or local jurisdiction requires.
- Hot work and fire extinguisher use for torch soldering.
- Safe lifting and hand truck use.
- Hazard communication: reading SDS for flux, solder, and thread sealant.

## Emergency

If you smell strong gas or a fire starts: stop work, do not flip switches, get everyone out, and shut gas at the meter only if safe. Call 911 and the gas utility from outside and give the site address. For burns, cool with clean water; for shock, turn off power before touching the person.

## Official sources

- [29 CFR 1926.21](https://www.ecfr.gov/current/title-29/section-1926.21) — Safety training and education
- [29 CFR 1926.28](https://www.ecfr.gov/current/title-29/section-1926.28) — Personal protective equipment
- [29 CFR 1926.102](https://www.ecfr.gov/current/title-29/section-1926.102) — Eye and face protection
- [29 CFR 1926.150](https://www.ecfr.gov/current/title-29/section-1926.150) — Fire protection
- [29 CFR 1926.352](https://www.ecfr.gov/current/title-29/section-1926.352) — Fire prevention (welding and cutting)
- [29 CFR 1926.416](https://www.ecfr.gov/current/title-29/section-1926.416) — Electrical — general requirements
- [29 CFR 1926.417](https://www.ecfr.gov/current/title-29/section-1926.417) — Lockout and tagging of circuits
- [29 CFR 1926.59](https://www.ecfr.gov/current/title-29/section-1926.59) — Hazard communication

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Source: HardHat Binder, operated by Leadspire LLC. Templates to be reviewed by a competent person before use; not legal advice; not affiliated with OSHA.
