How To Winterize A Raypak Pool Heater

Investing in a pool heater enables you to prolong the swimming season as you can enjoy pool water at a suitable temperature whenever you want. However, if you live in a region with freezing climates, it is essential to winterize your pool heater to protect it from potential frozen damage. If you wonder how you can winterize your Raypak pool heater, you are in the right place. We researched the topic, and these are our findings.

To winterize a Raypak pool heater:

  1. Power down the heater.
  2. Open the pressure switch.
  3. Remove the drain plugs.
  4. Disconnect compression fittings.
  5. Drain standing water.
  6. Store the pool heater.

We understand that is a lot of information to process at once. Dive to find further details on how to winterize your Raypak pool heater. We will also discuss some tips for troubleshooting a Raypak pool heater and how to re-set the pool heater.

beautiful house, swimming pool view from the veranda, summer day, How To Winterize A Raypak Pool Heater

How to winterize a Raypak pool heater

Typically, when water freezes, it expands. Therefore, if the water inside a Raypak pool heater freezes, the expansion causes parts of the pool heater to crack. It is recommended to winterize your heater and avoid repair or replacement costs arising from a damaged heater.

For this exercise, you will need:

  • A Phillips screwdriver
  • 7/16" open-end wrench
  • Flat blade screwdriver
  • Air compressor

This open-end wrench set is chrome plated for rust resistance. Check it out on Amazon.

These alloy steel flat-blade screwdrivers are heat-treated for strength and durability. Check them out on Amazon.

1. Power down the Raypak pool heater

Begin by switching off the power and gas supply to the heater. Next, shut off the system pump and disconnect water from the unit. Shutting off the power and gas supply ensures that the heater does not cycle if the water flow sensor malfunctions.

Typically, a pool heater has two gas valves. Switching both valves off eliminates the risk of an explosion if there is a slow leak.

To locate the gas valve knob inside the pool heater, use a flat blade screwdriver to remove the neural thumb screw on the door assembly, pull it off, and set it aside. You will then see the gas valve knob.

Set the knob to the off position and re-attach the door assembly. Firmly hold the door assembly in place by fastening the neural thumb screw.

2. Open the pressure switch

The pressure switch mitigates damage to your pool heater if the pool pump malfunctions or there is a problem with water flow.

To open the pressure switch, use the open-end wrench to carefully loosen the nuts connected to the top of the switch. Take care not to damage the nuts or the switch itself. Note that you do not need to detach the pressure switch entirely.

3. Remove the drain plugs

Typically, the pool heater will have two drain plugs, one on the inlet-outlet side and another on the rear side. Removing the drain plugs enables you to drain water from the pool heater.


Begin by removing the drain plug on the inlet-outlet side of the pool heater. If your heat exchanger has polymer headers, use the flat blade screwdriver to unscrew and remove the drain plug on the inlet-outlet side of the heater under the water pipes.

If the heater has cast-iron ASME headers, loosen the brass seated drain cork from the bottom of the inlet and outlet header.

Rear Side

You will need to detach the access panel to remove the drain plug on the rear side of your pool heater. Use the Phillips screwdriver to unfasten the screws holding the access panel on the return side of the heater in place and remove the access door.

For heaters with polymer headers, use the flat-blade screwdriver to unscrew the rear drain plug. Alternatively, if the heater has a cast iron ASME header, use the 7/16" open-end wrench to unscrew and remove the rear drain plug from the return header.

Ensure that you re-install the access panel and tighten the screws to secure it in place after you remove the rear drain plug. Additionally, carefully store the drain plugs as you will need to re-fix them back once the weather is more favorable for swimming.

4. Disconnect compression fittings

If your Raypak pool heater has ASME headers, it is recommended to detach the compression fittings from the pressure switch and the return header that connects to the 1/4" copper tube and allows the tube to drain.

5. Drain the standing water

Use an air compressor to drain excess water in the pool heater. You can also use a vacuum or leaf blower if you do not have an air compressor.

It is recommended to blow through the unions on the inlet and outlet ports of the heater. Blow from both sides of the ports to ensure that all the standing water is removed. Take care not to blow through the filters to avoid damaging them.

6. Store the pool heater

If possible, move the pool heater indoors to protect it from elements such as ice and snow. It's advisable to place a breathable cover on the heater to avoid trapping moisture inside.

Moisture buildup can lead to rusting and corrosion on the heater's interior. Further, place a fine mesh chicken wire on the large openings and vents around its exterior to rodent-proof the pool heater.

You should consider scheduling the heater's annual maintenance during this downtime when the unit is not in use.

Watch this video for a visual guide on winterizing a Raypak pool heater:

How to troubleshoot a Raypak pool heater

If your Raypak pool heater has malfunctioned and you wonder how to improve its performance, performing these activities might restore functionality. However, it is always sugested to have the heater checked by a professional, especially when you are not very handy.

Probe the power connection

Although pool heaters transfer heat from the outdoor air to the pool water, they still require electricity to function efficiently. Investigate whether the circuit breaker has tripped. Further, check whether the appliance's time clock is set to the 'On' position.

Restoring the power connection will get your pool heater working again.

Clean the gas burners

A dirty burner minimizes the pool heater's heating power.

To clean the burners:

  1. Turn off the gas supply and power connection to the heater.
  2. Locate and remove the burner tray. Ideally, it should be located on the front side of the heater.
  3. Use a wire brush to clean the burners gently.

Cleaning the burners improves the flame and provides sufficient combustion for reliable heating power.

Inspect the filters and strainers

A dirty filter or strainer with blockages keeps your pool from receiving a steady stream of water. In the absence of enough water, the pool heater will malfunction.

Cleaning the filters and strainers ensures that the pool receives enough water and thus functions as expected.

Investigate the error codes

Most digital pool heaters have a screen that displays the error code indicating the issue. The heater may exhibit various problems ranging from board failure to low water pressure. Use the operation manual to interpret the possible triggers to the problems and then follow the guide to resolve them.

Probe the temperature settings

Setting the pool heater's thermostat to a higher temperature than the water temperature is typical. When the temperature setting is higher, you will notice the difference in the water.

Otherwise, if you set the thermostat to low temperatures, you may assume that the pool heater is not working since the water is not heating up, while the issue may be the temperature settings.

How to re-set a pool heater

A pool heater is relatively expensive to buy and install. So, it is designed with safety measures to prevent avoidable damage. For instance, a digital pool heater goes into ignition lock-out to prevent overheating. Re-setting the heater enables you to clear the lock-out and continue enjoying your swimming water at a favorable temperature.

These measures will help re-set the pool heater:

  • Push and clasp the up and down buttons in the control panel to put the system on standby.
  • Re-set the pool's circuit breaker.
  • Use the up and down buttons to re-set the water temperature to a desirable level.
  • Investigate the error code and follow the recommended procedure to eliminate the trigger.

In Closing


If you live in regions that experience freezing climates, it is essential to winterize your Raypak pool heater to protect it from potential freeze damage. We hope that the information provided here will guide you in doing it correctly. Additionally, ensure that the heater is serviced annually to keep it properly working and ready for the swimming season.

It is recommended to troubleshoot the heater before calling in the technical experts. Troubleshooting can save you money, mainly when the issue is minor, and you can resolve it. However, if you lack the know-how or interest, call the experts. The service fee will be cheaper than repair costs incurred due to a significant pool heater failure.

Check out our other articles to discover more about pool heaters.

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What Size Propane Tank Do I Need For My Pool Heater?

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