How To Winterize The Attic Heat Exchanger

Complete Guide to Protecting Your SolarAttic PCS3 System During Winter

Proper winterization is essential to protect your SolarAttic PCS3 solar pool heater from freezing temperatures. Because the system is installed in the attic and contains water-filled components, failure to properly winterize can result in serious damage to the heat exchanger and plumbing system.

This guide explains exactly how to winterize the attic heat exchanger to ensure your system remains safe and ready for the next swimming season.

Why Winterization Is Important

When temperatures drop below freezing, any water left inside the plumbing or heat exchanger can freeze and expand. This expansion can cause:

• Cracked pipes

• Damaged heat exchanger coils

• Leaks and system failure

Proper winterization removes water from the system and prevents freeze damage.

When Should You Winterize Your PCS3 System?

You should winterize your system when:

• Outdoor temperatures begin approaching freezing

• The pool is being closed for the season

• The heater will not be used for an extended period

In colder climates, this is typically done in the fall before the first hard freeze.

Step-by-Step: How To Winterize The Attic Heat Exchanger

Step 1: Turn Off Power to the Heater

Before beginning any work, turn off power to the PCS3 system.

This ensures:

• Safe handling of the unit

• Prevention of accidental operation during winterization

Step 2: Shut Off Water Flow to the Heater

Close the valves that direct water to the solar heater.

This isolates the heater from the rest of the pool plumbing system.

👉 Related: Solar Pool Heater Plumbing Guide

Step 3: Drain Water From the System

All water must be removed from:

• Heat exchanger

• Plumbing lines in the attic

Water left in the system can freeze and cause damage.

Step 4: Blow Out Lines With Air

Using compressed air, blow out any remaining water from the plumbing lines and heat exchanger.

This step is critical because small amounts of trapped water can still freeze and expand.

Step 5: Open All Drain Points

Ensure any low points or drain valves in the system are opened so water can fully escape.

Gravity drainage helps remove remaining moisture from the system.

Step 6: Verify System Is Completely Empty

Double-check that:

• No water remains in pipes

• Heat exchanger is fully drained

• Lines are clear

This is the most important step in preventing freeze damage.

Important Winterization Tips

Always Remove All Water

Even a small amount of water can freeze and cause damage.

Use Compressed Air

Air pressure helps remove trapped water from the heat exchanger coil.

Check Attic Plumbing Carefully

Attic installations may have low spots where water can collect.

What Happens If You Don’t Winterize?

Failure to properly winterize the system can result in:

• Cracked heat exchanger

• Broken PVC pipes

• Costly repairs

• System downtime

Preventing freeze damage is much easier and less expensive than repairing it.

Preparing for Spring Startup

When reopening your pool:

1. Reconnect plumbing

2. Close drain valves

3. Restore water flow

4. Check for leaks

5. Turn power back on

Once restarted, the system will be ready to resume heating your pool.

Related SolarAttic Guides

To better understand your system, review these helpful guides:

• Solar Pool Heater Plumbing Guide

• PCS3 Solar Pool Heater Diagram

• Using Flex PVC Inside the Attic

• Proportioner T-Valve Flow Control Guide

These resources help ensure your system is installed, operated, and maintained properly.

Final Thoughts

Winterizing your SolarAttic PCS3 attic heat exchanger is a critical step in protecting your investment. By removing all water from the system and properly shutting it down for the season, you can prevent freeze damage and ensure reliable performance year after year.

Taking the time to winterize your system correctly will save you time, money, and potential repairs when the next swimming season begins.

Need Help With Your PCS3 System?

If you need assistance with winterization, installation, or system design, the SolarAttic team is here to help.

Visit SolarAttic.com to learn more about solar pool heating solutions and how to maximize your system’s performance.

Notice: The above Section 8. Winterization process is found on Page 18 of the Installation Manual. If you live in an area that requires you to winterize your pool, you will need to winterize the attic heat exchanger with the above process. Failure to do so, can result in damage to the water coil which is not covered under the warranty. It is the responsibility of the pool owner to properly winterize the attic heat exchanger. If you live in an area that does not hard freeze, but only occassionally threatens the pool with freezing, see the process on Page 19 of the Installation Manual. In this case, you will need to keep water running through the heat exchanger. Also, see Plumbing FAQs for further discussions.