When it comes to troubleshooting Hayward pool heater error codes, there’s not too much difference between the problem solving process for other gas-fired heaters, made by Jandy, Pentair or Raypak. The components of a Hayward pool heater are also similar to gas heaters made by other manufacturers.
Gas fired pool heaters are similar to a home gas-fired furnace, with the main difference being that a pool heater heats water and a home furnace heats air. Big difference, but other than that, they operate pretty much the same!
Troubleshooting Hayward Gas Heater Error Codes
Below is the troubleshooting guide for Hayward pool heater error codes. Error codes show up on the digital screen of the H-Series H150, H200, H250, H300, H350, and H400 gas models. Work through the chart below if your heater displays the following error codes.
| Code | Description | Information |
|---|---|---|
| bD | Internal fault/power-up error | On initial trial for ignition. Automatic reset is immediate once the gas valve relay check results are acceptable. |
| bD | Gas valve sensed as “ON” error | If valve is open when it should be closed the heater will shut down and go into lockout. Blower will operate until error condition is corrected. Automatic restart 2 minutes after error is corrected. |
| bD | Gas valve sensed as “OFF” error | If valve is closed but flame is sensed the blower will run for 5 seconds, then start a new ignition sequence. If error occurs 10 times during a call for heat the control will go into lockout. Automatic reset is 60 minutes. |
| bD | Data retrieval error | If control input data is corrupts, the heater will shut down and lockout. |
| HF | Flame present with gas valve “OFF” error | If flame is sensed with the gas valve off the control will go into lockout. The blower will run until error condition is corrected. When corrected, control will run blower for 5 s then automatically restart after 2 minutes. |
| PF | Electrical supply wiring error | This code will display if 120V polarity is reversed, low voltage is detected, or if the ground path is not sufficient. Reset is immediate after error is corrected. |
| AO | Blower vacuum switch open error | If the blower prover switch does not close after the blower starts the control will stop the ignition trial go into lockout. The blower will continue to run. Automatic reset is immediate after the switch closes |
| AO | Blower vacuum switch open when expected closed error | If the blower prover switch opens unexpectedly during operation the control will shut down and attempt to re-light. If the switch does not close after the blower starts the control will go into lockout with the blower running. Automatic reset is immediate after error is corrected. |
| AO | Blower vacuum switch open during post-purge error | If the blower prover switch opens during the postpurge cycle (heater is not firing) the control will display the error code. The post-purge cycle will be completed once the blower prover switch closes. |
| AC | Blower vacuum switch closed when expected open error | If the blower prover switch is closed before blower start-up the control will not start the blower. Automatic reset is immediate when the switch opens |
| IO | Igniter open error | If the control is not in lockout and senses that the igniter circuit is open when the blower is running the control will turn off the blower and go into lockout. Automatic restart 2 min after error is corrected. |
| SF | Thermistor error | An excessive temperature difference between the two thermistors (5 °F or more) or an “out of bounds” condition on both sensors (less than 10°F or greater than 180°F) will result in the error code. Automatic restart is 2 minutes after the error is corrected. |
| HS | Water Temperature Sensing Error | |
| Sb | Keypad button stuck closed error | If one of the keypad buttons is closed (or pressed) for more than 30 s the error code will be displayed but the control will continue to function. The error code will be cleared when the condition is corrected. |
| IF | Ignition failure error | If the control exceeds the maximum number of ignition retries or recycles the heater will shut down and go into lockout. Automatic reset is 60 minutes. |
| CE | Communication error | If communication between the ignition board and the display board is not established within 3 s of power-up an error will be displayed. After communication is established, if it is lost for 30 s, the error will be displayed. The error code will be cleared upon a valid data exchange between boards |
| LO | Limit string open error | If the limit string opens the heater shuts down and goes into lockout. Automatic restart is 2 minutes after the error condition is corrected and the limit string closes. See below for more detail |
| EE | EEPROM ERROR | An error was detected in the ignition control circuit board. |
Troubleshooting Hayward Gas Heaters
Below is a list of common issues that can arise with your Hayward pool heater. Unlike the error codes that show up on the digital screen, these problems don’t show up as an error notification. Work through the list below if your Hayward pool heater is on the fritz.
| Problem | Possible Cause | Possible Solution |
|---|---|---|
| Heater cycles on & off | 1. Filter or pump baskets are dirty. 2. External bypass is out of adjustment. 3. Internal bypass is broken or stuck. 4. Pressure switch is out of adjustment. 5. Lime scale in the heat exchanger. | 1. Clean filter or baskets. 2. Adjust bypass valve 3. Inspect or repair bypass 4. Adjust the pressure switch 5. Clean or replace the heat exchanger. |
| Sooting of heat exchanger | 1. High water flow (>125 gpm) into the heater. 2. Internal bypass is broken or stuck. 3. Lack of air combustion 4. Low gas pressure 5. Improper venting 6. Blocked heat exchanger 7. Blocked burners | 1. Install an external bypass 2. Inspect or repair the bypass 3. Improve air flow to the heater 4. Check the gas line size 5. Verify the exhaust is correct 6. Clean the heat exchanger 7. Clean debris off the burners |
| Pilot outages | 1. Low gas pressure 2. Restricted gas flow 3. Weak thermopile 4. High winds 5. Broken pilot gas tubing | 1. Increase pilot gas pressure 2. Clean pilot orifice 3. Replace the thermopile 4. Install a high wind stack 5. Replace the pilot tubing |
| Heater does not heat pool enough | 1. Heater is too small 2. Starting temperature is too low 3. Bad wiring or bad connections 4. Water flow is too low | 1. Add a solar cover 2. Add a solar cover 3. Check and repair or replace wiring and connections 4. Adjust bypass for more flow |
| Heater does not fire or light | 1. Bad gas valve 2. Pressure switch 3. Thermostat 4. High limits 5. On/Off switch 6. Fireman’s switch | 1. Use jumper wire to jump “TH” terminals 2. Use jumper wire to jump across wires on the pressure switch 3. Jump wires on thermostat 4. Jump wires on high limits 5. Jump wires on on/off switch 6. Jump wires on fireman’s switch |
Summary
We hope these charts help solve your Hayward pool heater problems. Pool heaters can be the most baffling piece of pool equipment, but if you consider the proper flow of gas, water and electric, you’re sure to find a solution quickly!
Troubleshooting pool heaters is a methodical process, or a process of elimination. First eliminate water flow issues, then gas flow issues, and finally the low voltage electric currents that run between pool heater components. And if you have Hayward heater error codes on display, that makes finding the problem almost easy!
My heater is not turning on, I don’t see an error message but the light next to the fire icon is not on but the light in the yellow triangle is on, any idea on what that means?
Hi Mark, hard to say if it does not display any error code, the caution symbol on a Hayward Heater is usually accompanied by an error code, LO being the most common, for low water flow. Here’s a link to the Hayward Heater Owners’ Manual, which may be helpful.
Hola tengo una caldera Hayward H400 PED2 durante el intento de encendido no enciende mí caldera después de 5 intentos me pone lF en la pantalla
Hola Raúl, Podría ser una de 4 cosas: encendedor, sensor de fuego, baja presión de gas o el tablero de control. La mayoría de las veces la válvula de gas está cerrada, el tanque de propano está bajo, el encendedor está roto o el sensor de fuego no está colocado correctamente. Buen suerte!
Hello, I have a H200 natural gas heater . The pilot lights, but when I try to jump test the gas valve it clicks and snuffs out the pilot light. Any ideas why? My pool is running, with water flow.
Hi Peter, I think you might be jumping the wrong terminals?
I have a Hayward H250, when I turn it on the green heat light is lit and the heater seems to make a howling sound. Suggestions?
Hi Steve, this can be from reduced flow, like a VS pump running on low speed, and some water vaporizing into steam. It could also be an obstruction in the exhaust, like a bird’s nest in there, blocking the air flow from the fan. Finally, it could be making the noise at the burner orifice, if one or more is not fully spewing gas, or is not ignited like the rest. Usually however, a howling or moaning sound from the pool heater, is low water flow.
I HAVE THE HEATER Hayward Universal H-Series H250 propane heater connected with the plumbing and electrical. but the digital display panel won’t light up, does the propane need to be connected and turned on to make the display panel work??
Hi Kenny, not to my knowledge, you should see some display even without gas hookup.
I have a Hayward HeatPro model HP21104T. I am getting a CEL code and the heater will not run. This occurred after a lengthy power outage. Anything I can do on my own to fix this? Thanks.
John, according to the manual, CEL is the code for “Panel not receiving data from control”. Meaning that your control (circuit board) may be damaged, or perhaps the cable is damaged or not connected fully. Call Hayward and speak to their tech support people, for more precise advice.
Does anyone know how to reset an “sf” error code after a new thermistor has been installed?
Hi Deb, SF (Sensor Failure) indicates that the temperature sensor (thermistor) is not getting good data to the circuit board. Check the wiring. If the wiring is Ok and the error persists, replace the sensor. For more info, see page 36 of the Hayward heater owners manual
My Hayward h250 propane heater keeps blowing fc1 and fc2 fuses immediately after plugging in. I also have voltage (115 volts)on both sides of the fuse holder with no fuse installed. I have no display showing.
Hi Mark, should it be 115V? Maybe the transformer is not functioning properly? The fuse is meant to protect the heater from 115V, as the voltage past the fuse should be like 28V, stepped down after the transformer. Put your power leads on both sides of the transformer, should be 115V IN, and 28V OUT, (or close to those numbers).
What is the incoming voltage on a H-150 pool/spa heater ?
I am trying to run power under ground in conduit and would like to know what size wire to run. Using natural gas as a heating source.
Most heaters can operate on 120V/240V, either one. What you want is the owner’s manual for the heater. The wire size may depend on the distance of wire run.
https://www.google.com/search?client=firefox-b-1-d&q=hayward+h-150+manual – the first pdf link is the older model H150, the second .pdf link is the newer H150 models, altho it may not make a difference.
I just had a power surge in my area and the heater has been turning on and won’t turn off. It won’t respond to the controls at all. I turned the gas off to it. It is a H400FDN series
Hi Josh, that sounds like the Display board, a circuit board that controls the display. IDXL2DB1930. Something got fried, sorry!
I have a Hayward H250 pool heater with a digital display. I can turn the temperature up but not down. It works fine otherwise, but the only way to stop it from heating up to 104 is by turning the power off to the heater. Is this just a problem with the thermostat button do you think?
Hi Carolyn, yes either the thermostat or other temp sensor, if present, would be responsible for that symptom.
Hi, I have a H250PED2. Have no power at all going to my control panel. I see a break on the back side of control board where the wires plug into a 6 prong male connector. Before I purchase all new control board assembly, does this sound about right? I know I have power going to the unit, as I can hear it go on and off in the transformer, when I hit the switch.
Hi Jim, as I like to say, “the problem lies, where the power dies”. If you have found a burnt spot or something broken on the circuit board, that is a likely power killing area.
Hi, when my Hayward pool heater is on I’m getting a sour odour from the exhaust. It’s not raw gas, but a sour smell. Gas pressure is ok. Any ideas?
I heard like a crank sound, as if something’s stuck between a propeller if there is. Then I saw a HS code. What should I do?
The “HS” (High Sense (water temperature) will appear if the water sensor is reading above 105° OR if the sensor detects an increase of more than 6° with-in 60 seconds. See page 40/41 in this Hayward Troubleshooting guide. https://www.afternic.com/forsale/haywarddocs.info?utm_source=TDFS&utm_medium=sn_affiliate_click&utm_campaign=TDFS_GoDaddy_DLS&traffic_type=TDFS&traffic_id=GoDaddy_DLS – the sound may possibly be a problem with the internal bypass, located in the front header.
I let it cooled down tho the temp was only 90 at that time.
If you’re correct that there’s a problem with the internal bypass, what should I do?
Well, you first need to inspect it, and if the parts are broken, replace them.
Thank you so much for taking time to answer all our concerns. God bless your heart!
I have a problem when the heater warms up it blows bubbles/cloudy bubbles. They disparate as they move through the pool. No air leaks and it only does this as the heater warms the water up during hot days.
Hmmm, not too sure about this question Jay, there must be some explanation. You don’t have a saltwater pool do you? Salt cells create cloudy bubbles, Ozonators too. But heaters? Not that I can think of, but something seems to be ‘aerating’ your water…? Anyone else have a scientific explanation?
So my Hayward melted the whole left sided plastic shrouds. Replaced the flow sensor as it seemed to run when lower RPMs on the pump and it now seems to cut it off when the RPMs on the pump drop like it should, and it will cut off when temperature reaches set heat of 93 for the spa. Went out today to find the lower plastic shroud melting again? 93 should not be “melting” the plastic shrouds? Any ideas? Heat exchanger has to be getting “too hot”? Looks clean though when I had it all apart.
Don, melted shrouds can indicate that the something may be laying on the burner tray, causing flames to shoot out a little sideways, or something is laying on (or clogging) the heat exchanger, allowing hot gas to build up inside the heater, slowing down the exhaust rate. And 93, that’s just the temp of the water, the flames are much hotter of course, that’s what is melting the plastic.
I have a F5 code and service light is on. What does F5 mean?
Hi Robin, an F5 code? I don’t see that code listed. You may give Hayward a call, and ask their tech support directly. 908-355-7995