Rheem Water Heater Dip Tube Replacement — What This Part Does
The dip tube is a long plastic pipe inside your water heater that attaches to the cold water inlet on top of the tank. Its job is to carry incoming cold water down to the bottom of the tank so the water heats evenly from the burner or element below. Without it, cold water dumps in at the top, mixes with your hot water, and you get lukewarm showers that run out fast.
Dip tubes fail from age, heat cycling, and hard water. Units built between 1993 and 1997 are notorious for defective polypropylene tubes that crack apart and shed white plastic flakes into your plumbing. Over time, any dip tube can split or break off from thermal expansion and contraction.
Signs It Needs Replacing
- Hot water runs out in 2 to 5 minutes You get a short burst of hot water, then it turns lukewarm or cold because incoming cold water is mixing at the top instead of heating at the bottom.
- Lukewarm or uneven water temperature Showers and taps never reach full hot because cold water is blending with the hot layer near the outlet.
- White plastic bits in faucet aerators or showerheads Small white flakes or chunks clog screens and strainers, a classic sign of a disintegrating dip tube.
- Water heater manufactured between 1993 and 1997 Units from this period often had defective polypropylene dip tubes that break down and shed debris.
- Temperature drops during a single shower Hot water starts strong but quickly becomes tepid as cold water mixes in at the top of the tank.
How to Replace It
- Turn off the gas supply valve or the circuit breaker for an electric water heater.
- Shut off the cold water supply valve going into the top of the heater.
- Open a hot water faucet somewhere in the house to relieve pressure in the tank.
- Attach a garden hose to the drain valve at the bottom of the tank and drain at least 3 to 5 gallons to drop the water level below the cold inlet at the top.
- Use a pipe wrench or adjustable wrench to disconnect the cold water supply line or nipple from the cold inlet fitting on top of the tank.
- Pull the old dip tube straight up and out through the cold inlet opening (it may come out in pieces if broken).
- Wrap PTFE tape approved for potable water around the threads of the new dip tube nipple or fitting if your model requires it, then insert the new tube carefully into the cold inlet and hand-thread the fitting.
- Tighten the cold inlet connection and reconnect the cold water supply line, taking care not to over-torque and crack plastic threads.
- Close all drain valves and faucets, turn the cold water supply back on, and let the tank refill completely while opening a hot faucet to purge air.
- Once water flows steadily with no air bubbles, restore gas or electric power and verify the heater fires or energizes normally, then check for leaks at the inlet connection.
The Part You Need
| Part | Notes |
|---|---|
| Rheem water heater dip tube (cold water inlet tube) | Amazon | Check your water heater’s model and serial number on the label plate on the side of the tank, then cross-reference the exact dip tube part number in the Rheem parts list for your model or purchase a universal replacement tube cut to your tank height. |
| PTFE tape or pipe thread sealant (potable water approved) | Amazon | Use only sealants rated safe for drinking water on any threaded fittings that require sealing per your model’s service instructions. |
Related Error Codes
If this part is failing you may also see one of these codes:
When to Call a Pro
If you are not comfortable draining the tank, working with threaded plumbing fittings, or purging air from the system, call a licensed plumber or water heater technician. If your unit is still under warranty, professional installation of the replacement dip tube may be required to preserve coverage. For gas models, any work involving burner access, gas line connections, or igniter components should always be handled by a qualified gas technician. For gas line, burner, or igniter work, or if you ever smell gas, stop and call a licensed technician.