Blower runs but no ignition then AO error code

check gas pressure if not enough it will not run call gas company sounds like you need more pressure

it could be a bad blower vac switch, and you may look at the rubber tubing going into the switch to ensure it hasnt dry rotted.

Either the fan is not working, or the fan prover (pressure switch) switch is stuck. If you can hear the fan going strong, it is most likely the switch. You may try to just clean it out, but you may need a replacement.


This error is produced when the blower prover switch does not close after the blower starts, the control will stop the ignition and go into lockout. Automatic reset is immediate after the blower prover switch closes.

If you keep having this problem, contact a reputable service company, especially if it's under warranty.

The link to the owners manual is below, it references fault codes, etc..

Hope this helps.

http://74.125.95.132/search?q=cache:4mAdY7bLfoQJ:www.haywardnet.com/products/Manuals/pdfs/Manual227.pdf+hayward+AO+error

You didn't indicate exatctly which model you have. But on most the AO error code is :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.Check to be sure combustion blower starts
If you don't have your manual you can download one for your exact model at : www.haywardnet.com

Check the tubing going from the blower to the blower vacuum switch. If there are any cracks, missing, or cut, it will give the same code. Rodents like to chew on this tube. Also, if the blower is not coming on at all, then you will get the same code, and the problem is not with the switch, it is likely in the blower.

Thank you for posting your question here on Fixya.com.

It sounds as if the air activated switch the tube you mention attaches to is not working. Pull the two wires from it and connect them to simulate the switch closing. Start up the heater to see if you get ignition. If so, replace the switch.

If this answer does not fix your problem, please comment with additional details prior to rating the answer. Positive feedback is appreciated once your problem is solved!

John

This error is produced when the blower prover switch does not close after the blower starts, the control will stop the ignition and go into lockout. Automatic reset is immediate after the blower prover switch closes.

If you keep having this problem, contact a reputable service company, especially if it's under warranty.

The link to the owners manual is below, it references fault codes, etc..

Hope this helps.

http://74.125.95.132/search?q=cache:4mAdY7bLfoQJ:www.haywardnet.com/products/Manuals/pdfs/Manual227.pdf+hayward+AO+error&cd=7&hl=en&ct=clnk&gl=us

I would have to agree with you concerning the control module.

My heater worked ok , btu made a clicking sound, now it shows a AO error? What can I do I dont have enough money to call a pool man again.