When your radiant heating system starts acting up, it can quickly disrupt the comfort of your home. High pressure is one of the most common issues, and you may be wondering: What is the best way to relieve pressure in a radiant heating system?
To relieve pressure in a radiant heating system, first turn off the boiler and let it cool. Then, open the pressure relief valve to release excess water until the pressure gauge reads between 12–15 psi. If the pressure remains high, inspect the expansion tank and drain additional water as needed.
Radiant heating systems are an efficient and comfortable way to warm your home, but maintaining proper pressure is essential for smooth operation and system longevity. With over four decades of experience in radiant heating, I’ve helped countless homeowners manage their systems effectively. In this article, I’ll walk you through safely relieving excess pressure and keeping your radiant heating system running smoothly.
Steps to Safely Relieve Pressure in a Radiant System
Relieving pressure from your radiant heating system is a straightforward process when done correctly. Follow these six steps to address high pressure:
- Turn Off the Boiler
- Shut down the heating system to prevent water from circulating.
- Allow the system to cool completely to avoid burns or injury.
- Locate the Pressure Relief Valve
- Find the valve, typically near the boiler or along the system’s piping.
- Place a bucket or container under the valve to catch discharged water.
- Open the Relief Valve
- Slowly open the valve to release water and reduce pressure.
- Close the valve once the pressure gauge reads between 12–15 psi.
- Inspect and Adjust the Expansion Tank
- Check if the expansion tank is properly pressurized.
- Use an air pump to adjust the tank’s air pressure to the recommended level.
- Drain Additional Water if Needed
- If pressure remains high, use the system’s drain valve to release more water.
- Attach a hose to the valve to direct water safely into a drain or container.
- Restart the Boiler and Recheck Pressure
- Restart the boiler and check the pressure gauge to confirm it stays within the recommended range.
Understanding Normal Pressure Ranges for Radiant Systems
Maintaining the correct pressure in your radiant heating system is critical to ensure it operates safely and efficiently. Pressure that is too low can lead to poor heating performance, while pressure that is too high can cause damage to the system’s components. Use the table below as a guide to determine whether your system’s pressure is within the appropriate range and what action to take if it’s not.
| System Condition | Recommended Pressure (psi) | Action |
|---|---|---|
| Cool System | 12–15 psi | No action needed. Your system is operating normally. |
| Warm System | 15–20 psi | Monitor regularly to ensure the pressure doesn’t continue to rise. |
| High Pressure (>20 psi) | Above 20 psi | Release pressure and inspect the system for issues such as a faulty expansion tank or overfilled water. |
How to Interpret These Ranges:
- Cool System (12–15 psi): When the system is not in use or the boiler is off, the pressure should remain in this range. No action is necessary.
- Warm System (15–20 psi): As the system heats water, some pressure increase is normal. However, frequent checks are recommended to prevent the pressure from exceeding safe limits.
- High Pressure (>20 psi): If the pressure gauge shows more than 20 psi, immediate action is required. Follow the steps outlined in the guide to safely release pressure, and inspect key components such as the expansion tank and relief valve.
By understanding and regularly monitoring these pressure ranges, you can prevent damage to your system and ensure consistent heating performance.
Why Is My Radiant System Pressure Too High?
Common causes of high pressure in radiant systems include:
- Overfilled System: Adding too much water can increase pressure.
- Faulty Expansion Tank: An improperly pressurized or damaged tank may not absorb excess pressure.
- Clogged Relief Valve: Dirt or debris can block the valve, preventing proper function.
- Temperature Fluctuations: Rapid heating or cooling cycles can lead to pressure spikes.
Preventing High Pressure in Radiant Heating Systems
To avoid future pressure problems, follow these preventative tips:
- Regularly Monitor Pressure: Check the gauge monthly to ensure it stays within normal ranges.
- Service the Expansion Tank: Ensure it’s properly pressurized and free of leaks.
- Maintain the Pressure Relief Valve: Clean or replace the valve annually to keep it functioning properly.
- Schedule Professional Maintenance: Regular servicing by experts ensures all components are in good working condition.
For additional guidance, visit Energy Star’s Guide to Efficient Heating Systems.
When to Call Bear Valley Plumbing Heating and Air
If your radiant system continues to experience pressure issues, our licensed technicians can help. We specialize in:
- Diagnosing high-pressure problems.
- Servicing and replacing expansion tanks.
- Repairing or replacing faulty relief valves.
Contact Bear Valley Plumbing Heating and Air Today
Don’t let high pressure disrupt your radiant heating system. Call Bear Valley Plumbing Heating and Air at 909-584-HERO or visit 584Hero.com to schedule an appointment.
With decades of experience serving the Big Bear community, we’re here to keep your home warm and your systems running smoothly.
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- What’s the Most Efficient Way to Heat a Home in Big Bear, CA?
- 10 Quick Tips About Saving Money on Big Bear Heating
FAQ: Radiant System Pressure Relief
How do I know if my radiant heating system’s pressure is too high?
If your system’s pressure gauge reads above 20 psi, the pressure is too high. You may also notice water leaking from the pressure relief valve, which is a safety mechanism to release excess pressure.
What is the ideal pressure for a radiant heating system?
The ideal pressure for most radiant heating systems is between 12–15 psi when the system is cool and up to 20 psi when operating. If pressure exceeds these levels, it’s time to take corrective action.
What causes high pressure in a radiant heating system?
Common causes include:
- Overfilled system: Adding too much water during maintenance.
- Expansion tank issues: A faulty or improperly pressurized expansion tank.
- Clogged relief valve: Dirt or debris preventing the valve from functioning correctly.
- Temperature spikes: Rapid changes in water temperature can increase pressure.
How do I locate the pressure relief valve on my radiant heating system?
The pressure relief valve is typically located near the boiler or on the main piping of the radiant heating system. It is a small valve with a lever or cap that allows you to manually release water to reduce pressure.
Can I manually adjust the pressure in my radiant heating system?
Yes, you can manually adjust the pressure by releasing water through the pressure relief valve or drain valve. However, you must turn off the boiler and let it cool before making adjustments.
Why does my radiant heating system keep losing pressure after I release it?
Consistently low pressure could be caused by:
- Leaks in the system: Check pipes, valves, and connections for water drips.
- Faulty expansion tank: An underperforming tank may not hold pressure correctly.
- Malfunctioning pressure relief valve: A damaged valve may not close properly after releasing pressure.
How often should I check the pressure in my radiant heating system?
It’s a good idea to check the pressure gauge monthly, especially during peak heating seasons. Regular monitoring helps you identify potential issues early and maintain optimal system performance.
What should I do if my radiant heating system has low pressure?
If the pressure is below 12 psi, you can add water to the system using the boiler’s fill valve. Open the valve slowly and monitor the gauge until it reaches the recommended pressure range (12–15 psi). Be careful not to overfill the system.
How do I reset the pressure relief valve on a radiant heating system?
To reset the pressure relief valve, close the valve completely after releasing excess water. If the valve continues to leak or fails to maintain pressure, it may need cleaning or replacement by a professional.
Is it safe to release pressure from a radiant heating system myself?
Yes, it is generally safe to release pressure yourself by following proper steps: turning off the boiler, letting the system cool, and slowly opening the relief valve. If you are unsure, it’s best to consult a licensed HVAC technician.
Can high pressure damage my radiant heating system?
Yes, prolonged high pressure can cause leaks, damage to pipes, and stress on components like the boiler and expansion tank. Address high pressure promptly to avoid costly repairs.
How do I test if my expansion tank is causing high pressure?
To test the expansion tank:
- Locate the tank near the boiler.
- Tap the tank lightly—if it sounds full of water, it may not be functioning properly.
- Use a tire pressure gauge to check the air pressure inside the tank. It should match the system’s pressure.
What tools do I need to relieve pressure in a radiant heating system?
The tools you may need include:
- A bucket or container to catch water.
- A wrench or screwdriver to open the pressure relief valve.
- A hose for draining water (if using the drain valve).
When should I call a professional to fix pressure issues in my radiant heating system?
Call a professional if:
- The pressure relief valve or expansion tank needs replacement.
- Pressure issues persist despite troubleshooting.
- There are visible leaks or signs of damage in the system.
If you are looking for a Big Bear plumbing, heating & air conditioning contractor, please call (909) 584-4376 or complete our online request form.
Category: Heating, Heating Repair & Maintenance
