Quick Answer
A simple valve replacement might cost you $20-$50 for the part if you do it yourself, but a pro will charge you more like $200-$400. If it's high pressure, you're looking at a bigger job like adding an expansion tank or a pressure reducing valve, which will be significantly more expensive.
Common Symptoms
Possible Causes
Step-by-Step Diagnosis
Step 1
Observe the leak. Note if it's a constant drip, a stream, or if it only happens when the water heater is actively heating.
Step 2
Test your home's water pressure. Use a pressure gauge on an outdoor spigot to get a reading. Normal is 40-80 PSI; anything higher is a problem.
Step 3
Check the temperature setting on your water heater's thermostat. It should be set to 120-125°F, not maxed out.
Step 4
Carefully 'burp' the valve by lifting the lever for a few seconds to see if it clears any debris. Be prepared for it to leak more afterward if the seal is old.
Step 5
Check for the presence and function of a thermal expansion tank, which would be a small tank plumbed into the cold water line above the heater.
DIY vs Professional Costs
| Repair Type | DIY Cost | Professional Cost | Time Required |
|---|---|---|---|
Replacing the TPR Valve | $20-50 | $200-400 | 1-2 hours |
Installing a Thermal Expansion Tank | $50-150 | $350-650 | 2-3 hours |
Installing a Pressure Reducing Valve | $60-200 | $400-700 | 2-4 hours |
When to Call a Professional Water Heater
- If you see steam or scalding hot water actively discharging from the valve, shut down the system and call a pro immediately.
- If you've diagnosed high water pressure (over 80 PSI) as the cause, as this requires installing a pressure-reducing valve.
- If you are not comfortable or experienced with draining a large water tank and using pipe wrenches to replace the valve.
- If you replace the valve and it continues to leak, indicating a more complex issue like thermal expansion.
- If the leak is a strong, continuous stream, which could lead to flooding or significant water damage quickly.
Prevention Tips
- Keep your water heater temperature set at a safe and efficient 120-125°F.
- Test your home's water pressure annually with a cheap gauge to catch high pressure before it causes problems.
- If your pressure is high (over 80 PSI), have a Pressure Reducing Valve (PRV) installed.
- Ensure you have a functioning thermal expansion tank, especially if you have a PRV or other closed-loop system.
- Flush sediment from your water heater tank once a year by draining a few gallons from the bottom drain valve.
- Proactively replace your TPR valve every 5-7 years, especially if you have hard water.
Frequently Asked Questions
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