How to plumb a washing machine can be a straightforward DIY task—if done correctly. Miss just one step or use the wrong connection, and you could end up with leaks, flooding, foul odors, or blockages that cause water damage to your home.
Today’s washing machines are more advanced and powerful than ever, which also makes them more sensitive to poor installation. For example, an incorrectly secured drain hose can siphon wastewater back into the drum, or a loose water inlet can cause catastrophic flooding while you’re out of the house.
This comprehensive guide walks you through every stage of how to plumb a washing machine — from the tools you need, how to prep your space, how to set up the water and drainage connections, and how to test and troubleshoot your installation.
Preparation: Tools, Planning & Safety
Essential Tools & Materials:
Adjustable wrench or spanner
Spirit level
PTFE (Teflon) tape for threaded fittings
Inlet hoses (if not included with machine)
Jubilee clips or hose clamps
A large towel or tray to catch water drips
Bucket
Utility knife (to trim hose ends if needed)
Flashlight
Zip ties or brackets for hose support
Optional Tools:
Self-sealing waste trap (HepVO or equivalent)
Pipe insulation (to protect hoses from cold walls)
Leak detector spray
Safety First:
Ensure that your washing machine is unplugged from the electrical outlet before doing any work.
Never work with wet hands near electrical components.
If you’re unsure about the quality of your home’s plumbing system or wiring, consult a qualified tradesperson before starting.
Choose the Right Location
Before you even bring in the washing machine, confirm the installation space:
It must have a cold water supply, wastewater outlet, and electrical power.
The floor must be solid and level—concrete or reinforced wood is ideal.
Avoid carpeted areas or rooms without proper ventilation, as moisture build-up can lead to mold.
Ideal Placement Locations:
Kitchen or utility room: Easiest due to proximity to plumbing.
Garage or basement: Fine if pipes are protected from freezing and you have proper drainage.
Bathroom: Permissible but should follow local electrical safety codes, especially regarding outlets.
Turn Off the Water Supply
This is non-negotiable.
Locate the isolation valves on your cold water (and hot, if needed) supply lines. These are typically small levers on the pipes where your old machine was connected.
Turn them clockwise to shut off water. Open a faucet elsewhere in the house to confirm the water is no longer flowing.
Place a bucket beneath the valve connections to catch any residual water when you remove the old hoses.
Water Inlet Connection: Cold and Hot Water Supply
Most modern washing machines are cold fill only, but some older or higher-end models still support hot water inputs.
Connecting the Inlet Hose(s):
Wrap PTFE tape around the threaded ends of your water valves to ensure a watertight seal—3-4 turns around the thread is enough.
Connect the hose(s) to the back of the washing machine. Most have color-coded ends: blue for cold, red for hot.
Tighten the connections by hand first, then finish with a quarter turn using your wrench. Do not overtighten—this is a common DIY mistake.
Connect the other end to the wall-mounted water valves in the same way.
Make sure the hoses are not kinked or stretched too tightly, especially if the machine will be moved back into a snug space.
Drain Hose Setup: Standpipe vs. Sink Trap
Your washing machine’s waste water must go somewhere—and it must go there without backflow, siphoning, or spilling onto your floor.
Option 1: Standpipe
A standpipe is a vertical pipe that connects to the home’s main waste system. It should be:
18–30 inches (450–750 mm) above the ground
Fitted with a P-trap to prevent sewer gases
Large enough to handle the rapid discharge rate of modern washers
Installation steps:
Insert the drain hose into the standpipe at least 6 inches deep, but no more than 8 to avoid siphoning.
Use a bracket or U-bend clip to hold the hose in place.
Do not seal the hose into the pipe—airflow is necessary to prevent vacuuming water back into the machine.
Option 2: Sink Trap Connection
If near a sink or dishwasher, you can connect the hose to a washing machine-compatible sink trap.
Steps:
Attach the hose to the trap spigot using a jubilee clip.
Make sure it’s slightly sloped downward from the machine to the trap.
Avoid bends or dips in the hose that could trap water and lead to smells.
Level the Machine
Using a spirit level, check the washing machine is flat on the floor:
Adjust the feet at each corner by turning clockwise to raise or counterclockwise to lower.
A machine that isn’t level will vibrate excessively, possibly loosening your plumbing connections over time.
Once adjusted, lock the feet with the built-in nuts (if available).
Tip: Run the level front-to-back and side-to-side for full accuracy.
Electrical Connection & Power Supply
The washing machine must be connected to a grounded electrical outlet.
Do:
Plug into a dedicated socket, ideally with a fuse.
Use a circuit protected by a residual current device (RCD) if located in a bathroom or garage.
Keep the plug easily accessible (don’t push the machine all the way in and trap the cord).
Don’t:
Use extension cords or multi-plug adapters.
Place the cord under rugs or heavy objects.
If you’re adding a new socket or running wiring across wet areas, consult an electrician.
Final Check & Leak Testing
Before using the machine, you need to simulate a full wash cycle to make sure everything is secure.
Open the water supply valves slowly. Listen for any dripping.
Plug the machine in.
Run an empty short cycle (like “Rinse & Spin”) to test the inlet and drain systems.
Watch the inlet hose connections during the fill cycle and drain hose during the spin.
After the cycle, check around all hoses and pipes with your hand for any moisture.
If needed, retighten the fittings slightly. Don’t overtighten.
Troubleshooting Common Issues
| Problem | Possible Cause | Solution |
|---|---|---|
| Water leaking at hose connections | Loose fittings or missing tape | Retighten or apply PTFE tape |
| Machine not filling | Closed valves or kinked inlet hose | Open valve fully, check hose bends |
| Water backing into the drum | Incorrect standpipe height or siphoning | Raise pipe or install anti-siphon loop |
| Unusual noise when draining | Hose too tight or restricted flow | Loosen bends, resecure with brackets |
| Drain smells | No trap or water sitting in the hose | Install P-trap or air admittance valve |
Optional Enhancements
Want to take your installation to the next level?
Drip Tray: Install under the machine to catch leaks.
Water Hammer Arrestor: Prevents pipe noise during fast valve closing.
Leak Detector Sensors: Can shut off water automatically if a leak is detected.
Washer Pan with Drain: Especially useful in upstairs laundry rooms.
Maintenance Tips for Long-Term Safety
Check hoses monthly for bulges, leaks, or stiffness.
Replace hoses every 3–5 years, even if they seem fine.
Clean the drain filter every few months to prevent clogs.
Run a hot wash with baking soda and vinegar to remove detergent buildup.
Leave the door open after washes to prevent mold.
When to Call a Professional
There are times when DIY simply isn’t the right option. Call a plumber or appliance technician if:
Your home has old or corroded plumbing.
You need to install new water lines or a drain trap.
You’re installing a machine in a new location without existing infrastructure.
The washing machine displays error codes after setup.
You live in an apartment with shared water systems or regulatory restrictions
If you still need a plumber you can contact us
