How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site.
    Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask HVAC Guru Your Own Question
Category: Pool and Spa
Satisfied Customers: 14410
Experience:  15yrs in the HVAC industry with certificates and degrees.
Type Your Pool and Spa Question Here...
HVAC Guru is online now
A new question is answered every 9 seconds

Our Hayward H400FDP pool heater gets error code HS, makes a

Customer Question

Our Hayward H400FDP pool heater gets error code HS, makes a lot of noise and shuts down every time we turn it on. There's no problem with the water flow. What could be causing this? Thanks.
JA: I'll do all I can to help. Tell me a bit more about what's going on so we can help you best.
Customer: The pool heater won't stay on and gets error code HS... what other information would you like to know?
JA: Is there anything else important you think the HVAC Technician should know?
Customer: no
JA: OK. Got it. I'm sending you to a secure page on JustAnswer so you can place the $5 fully-refundable deposit now. While you're filling out that form, I'll tell the HVAC Technician about your situation and then connect you two.
Submitted: 11 months ago.
Category: Pool and Spa
Expert:  HVAC Guru replied 11 months ago.

Hello and thanks for using this service, if you have been waiting do not worry or get upset. I am HVAC Guru an extremely experienced tech on the site and I try to get to as many customers as I can. I just picked up your question now. NOTE it takes time for me to type research and add links so please wait for me to respond back I can only do this so fast. Secondly I am not paid anything until you rate my service good using the STAR RATING LINK at the top of your page, the money is paid to the site not me directly.


HS=A) Inlet water temperature sensor is reporting a temperature in excess of 104°F. Normal operation resumes 2 minutes after inlet water temperature sensor reports temperatures of 104°F or less. This error functions in both normal and remote thermostat modes. or B) Inlet water temperature sensor is reporting a temperature change at a rate faster than 6°F in 60 seconds, indicating a potentially damaging low water flow conditon. Normal operation resumes when temperatures stabilize. If this condition is detected 3 times, the heater will lock-out until the electrical power is cycled off and back on.

If it is making a ton of noise the pump impeller has likely broken hence the error hear since it is not pumping water. I would say you need a new pump.

All I ask is please use the Star Rating Link at the top of your page before leaving, that is the only way I am paid anything through the site and that will also get you a DIRECT LINK emailed to you to get back to me! are greatly appreciated so thank you very much for using this service. If you have any other questions just post back to me here anytime!

Customer: replied 11 months ago.
It can't be that we need a new pump... our pump is working fine.
Expert:  HVAC Guru replied 11 months ago.

Can you narrow down where the noise is coming from?