Raypak Pool Heater Won’t Ignite [9 Easy Fixes]

There can be a wide range of reasons why your Raypak pool heater won’t ignite. A clogged pilot orifice, faulty pilot assembly, defective flame sensor and blower stops operating are the main culprits.

Besides obstructed pool filters, insufficient pump pressure, broken gas valve, blocked burner orifice and tripped safety switches are also probable causes of ignition failure. 

Keep reading our Raypak pool heater troubleshooting manual to ignite your pool heater.

Table Of Contents

Raypak Pool Heater Won’t Ignite [9 Easy Fixes]

In this section, we will take an in-depth look at the causes behind your Raypak pool heater not igniting. We will also share the simplest solutions for Raypak pool heater ignition failure.

Note: You can also read how to fix Jandy pool heater won’t ignite problem.

1. Clogged Pilot Orifice

The pilot flame is necessary to light up the burners. It is the first piece of the ignition process. If the pilot orifice is clogged with grime, dirt, and dust, it may not light up. This results in ignition failure.


Here’s how you clean the pilot orifice after carefully removing it from its secure mounting.

  • Clean the tip of the orifice with a fine-grit sandpaper. This will eliminate any oxidation or mineral deposits that have accumulated in the gas pilot orifice’s crevices. 
  • Push a sharp wire brush into the narrow pilot slot to remove all blockages from the tube. 
  • A can of compressed air is useful to dislodge dust or particles. A few blasts of compressed air will guarantee that the pilot tube is reattached to a clean surface.

2. Damaged Pilot Assembly

If your pilot light won’t ignite, the pilot assembly could be damaged. A damaged pilot assembly is relatively rare but it could happen. Without a working pilot, your Raypak pool heater won’t ignite. 


Remove the pilot assembly. Look at the pilot assembly carefully for signs of damage. Clean the pilot assembly thoroughly and reattach it to the heater. Try igniting the pilot and if it doesn’t light even after cleaning, it needs to be replaced. 

3. Defective Flame Sensor

The flame sensor is used to sense the pilot light and then allow the gas valves to release gas. Without sensing the flame, the gas won’t come out of the valves. This mechanism is there to protect you from a possible gas leak. 

However, a bad flame sensor can fail to detect the pilot flame even when it is lit. For that reason, a defective flame sensor is one of the most common causes of ignition failure.


Do the following to see if the flame sensor is successfully delivering a signal to the gas valve.

  • Keep the power supply to the heater on. Take a multimeter that can measure microamps (A). Make a series connection in which the multimeter will be in the middle of the sensor terminal and the wires that lead into the gas valve.
  • There are two probes on the multimeter. Connect one to the lead from the flame sensor and another to the sensor terminal. Change the thermostat setting to a higher temperature and once the burners are lit, check the reading. If the reading isn’t between 5-10 A, replace the flame sensor.

4. Blower Not Operating

Your heater’s failure to light up could be due to a faulty blower. The heater will not obtain enough airflow if the blower is not turned on. 

It is more likely to overheat as a result of this, which can hurt the unit. So, to protect the unit, the heater doesn’t light.


Make sure the fan is turned on. Otherwise, the blower motor could be damaged. It’s possible that the problem is with the wiring, or that the blower is receiving insufficient voltage.

You must figure out which of these problems is causing the fan to fail. Verify the connections using the Raypak pool heater wiring diagram below.

Fig: Raypak pool heater wiring diagram

5. Obstructed Pool Filter

A pool filter can quickly become clogged with debris and silt, limiting the pool heater’s water flow. A minimal water flow rate is required for your heater to function. This could explain why it won’t light.


Check the elements in the pool filter to see whether they are unclean. If the pool filter appears to be unclean, backwash it.

Clean the skimmer basket in the pool. It is critical that the pool filter be cleaned every 2-3 months. A blocked pool heater is the most common cause of pool heater problems.

6. Insufficient Pump Pressure

Ignition failure is caused by low pump pressure. The following things could be wrong if your pump pressure reading is lower than needed.

  • The skimmer basket or heat pump is obstructed
  • low water levels
  • Jammed skimmer lines
  • The impeller in the pool pump is blocked or faulty
  • Leaking inlet lines to the water pump
  • Leak in multiports or 3-way valves 


Check to see that the skimmer bucket is vacant and the lines are clear. Look for damage to the pool pump impeller and repair it if necessary. Clean out dirt from the impeller.

Ensure that the water level is correct and that the lines leading to the pump are not fractured or damaged. If there are any air leaks, bleed out the pump.

If the pressure gauge is broken, replace it. If the problem persists, replace the multiports or 3-way valves.

7. Broken Gas Valve

The gas valve maintains the gas flow at the pool heater burners. It will only let gas release after the thermostat calls for heat.  

As a result, your heater will not fire if your gas valve malfunctions and fails to release gas when called for.


On the top or side of the gas valve, look for the two wires attached to the solenoid terminals. Remove the connections from the terminals of the gas valve.

A push-on clip that may be retracted connects each wire to a termination. Make a mental note or click a picture of where the wires connect to the valve so you can reconnect them later.

Set the multimeter’s test control to “mV.” Connect the tester probes of the multimeter to each of the gas valve’s leads.

A usual reading ranges from 145 to 195 millivolts. If the reported reading falls outside of this range, the gas valve is faulty. It will require replacement.

8. Blocked Burner Orifice

Calcium deposits or dust may have blocked your burner opening. This makes it hard for the burners to ignite, causing an ignition failure.


To get your Raypak pool heater operating again, you’ll need to replace the burner tube. Follow these instructions to change the tube on your own:

  • Power off your pool heater and turn on a nearby faucet for five minutes. Remove the water heater’s lowest access panel.
  • Remove the old tube’s base from the gas valve by loosening and removing it. It is necessary to replace the burner tube.
  • With an adjustable wrench, tighten the base of the replacement burner tube to the gas valve.
  • You can test the water heater’s functionality by turning it on. If the problem continues, hire a technician to thoroughly inspect it.

9. Tripped Safety Switches

The high limit switch, water pressure switch, and rollout switch are the safety switches found in a Raypak pool heater.

If one or more of them are tripped, your pool heater won’t turn on and not ignite until the switch has been closed. 

You may get an error code to indicate which switch has tripped. Check the raypak pool heater manual to see the error codes that can show up.


After fixing the cause that made your heater’s safety switch trip, you need to reset your heater.

The Raypak pool heater reset process is simple. All you need to do to reset your heater is to turn it off and wait for a while before turning it back on.


Can you oversize a pool heater?

You can’t get a pool heater that is too big for your pool. The bigger the heater, the quicker it warms up the pool water, and the less likely it is to start short-cycling.

Does the pool heat faster with a pump on high?

Yes. Higher flow rates improve heat transfer efficiency. However, total efficiency and expense must be considered. Lowering the pump’s speed may be worth the extra heat loss.

How cold is too cold for a pool?

The ordinary swimmer should avoid swimming in water that is below 70 degrees Fahrenheit, regardless of where they are. But the truth is that 70 degrees are still quite chilly.

How can I heat my pool faster?

A gas pool heater and a sun cover are the quickest ways to heat your pool. Whatever method you use to heat your pool, you should have a solar cover in place to assist keep the heat in.

What is a pool flow meter?

A swimming pool flow meter is a gadget that determines the rate at which water flows through your system. The speed is measured in gallons per minute or GPM by this gadget.


Hopefully, now you know how to act when your Raypak pool heater won’t ignite. It can be tough to narrow down which of the above causes is the culprit.

If you have little knowledge of pool heaters, you may be better off hiring a professional. 

About David

David is a man who loves doing research and finding out the best solution to any type of heating appliance issues like heaters and fireplaces. Whenever he finds the perfect solutions to any issues of heating appliances after doing in-depth research, he loves to share them with his readers. In fact, his aim is to help his readers to fix the issues with their heating appliances easily.More about us .

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