Please send your phone number by private messaging if you'd like someone to call or someone will reply here.

When you say the LO code is usually caused by a dirty filter, which filter are you referring to? The pool filter, or is there a filter in the heater also?

pool filter

I have a Hayward pool heater Mod# H200FDN. Pool is 7 yrs old and we just bought the house. The heater when I turn on gas goes through a cycle then the service light comes on.

Hi there, please reach out to your local Hayward Service Center for assistance. If you’d like to provide your zip code, we can provide their contact information.

I got it running this morning. Thank you

Great, enjoy your pool!

getting the same ‘lo’ error. we did backwash as Noted, but still appears. we have a sand filter so what do you recommend we should try next?

We can ask a Hayward tech to reach out on Monday. What is your email address and phone number please?

Hi there. I have a Super Pump VS and the Universal H heater on natural gas. when the pump is running at 2000rpm or less i get the LO error, but not on higher speeds. Is it normal? btw, I also have a sand filter. Thanks.

Andre, we’ll ask a tech to contact you. Please message us with your phone number.

I’m having the same problem but heater is not restarting itself. Help!

Sure, happy to help. Please dm us with your name and phone number and a tech will reach out.

Ron byers 815-353-0734

How long before someone calls

Hi Ron, we’ve replied on private messaging. Someone will call tomorrow.

I have an H150FDN which is often on LO. I’ve cleaned both filters but this seems to happen every second day. Yesterday, the heater stopped working. The warning light next to the LO setting is on. I would really like to have this resolved once and for all. Ty

Thanks, please dm us with your name and phone number and a Hayward tech will call next week to help.

We have a Hayward H150FDN and the LO keeps coming on. The filter is brand new so I know that is not the problem . What else can I try and do or look at

I’m beginning to think haywards are not the way to go. After I spent a ton of money on a useless object

Please dm your phone number and email address and a Hayward tech will reach out to help on Monday.

Hi. I have a H200FDN heater that was working last week and now I’m getting a LO error with service light. Just opened for the season and filter is clean. Any other suggestions?

Happy to help, Michael. Please dm your phone number and email address and a tech will reach out.

Hello, even when I try and turn the heater off (and filter off) I’m getting the LO code with the warning sign. Is there a way to reset this? When it’s running there isn’t an error. I recently upgraded to a VS pump and don’t remember this happening when I wanted to shut the heat off while the filter was off

We can ask a Hayward tech to call you to help. Please dm your phone number.

I've got H250FDN and am having the same problem. Water flow seems normal but I keep getting the "Lo" reading. Can you guys help?

Hi Jason, please DM your contact information and a tech service rep will be in touch.

Hi I just hooked up a new 150,000 Hayward. With pump on low speed I get the LO code. So I put on high speed and LO code immediately goes away but then within 30 seconds I get HS code and shut down. 724-977-7371

Hi there, a Hayward tech will call you tomorrow to help.

Hey there. We are having similar troubles with LO code on pool heater. It is less than 3 years old and tries to fire up but then LO code comes on. Pool

was opened a few weeks ago and seemed to be working for the first week. i think has been an issue ever since we have had it since the pool

never seems to get up to temp. We have it set for 82 and it has been 70-72 in the morning even when it has been warm out. Any help would be appreciated Im not very handy ao if there is a rep in southwestern ontario that would be even better.

We have the same issue. Pool is one year old. Hayward system shows LO and the service light is on. Heater seems to be working when we turn it on though. Just worried that something is wrong. Can someone contact me?

I was told on this thread a Hayward rep would call if I DM’d and I never heard back. I called Hayward Canada last week and apparently that service light and the LO code is normal when the heater is off. I don‘t recall that happening when I had the single speed pump and tried to turn heater off but I was assured by Hayward at this is “normal”. Hope that helps.

Hi,

Have a new H250FDN--got the LO code and backwashed and cleared it--next day had to vaccum as pool was dirtier than normal (since waiting for new heater). Backwashed for 5 min but cannot clear LO code now. Do I need to backwash several times you think? I have 22 PSI showing on filter which is high--(put in new sand last week).....I am thinking I still have a dirty filter--what do you think?

Our Hayward tech would be happy to advise. Please dm your phone number.

Same issue with Lo error when off but heater works with a bo(bypass operation) code. When shut off, it goes back to Lo with service light. Sand filter has been backwashed and baskets emptied. Any help please?

A Hayward tech can call you if you’d like to dm your phone number and email address please.

Same story here. We just installed a H250FDN and went so far as to replace our cartridge at the same time. We have a 1.5 HP pump and the pressure coming out of the return is strong. Also just adjusted the water pressure valve to wide open. Still getting the LO error.

Hi Justin, please dm your email address and phone number on our Facebook page or Twitter profile and a Hayward tech can contact you to help. You can also reach out via email to marketing@Hayward.com.

So, I had a Hayward Tech come to the house and told me the code was “normal” upped the pump pressure and the code went to b0(bypass operation) and he told me to leave it there and all was normal. I don’t think he knows what he was doing as he said “this system is very difficult, I’m not going to charge you for the visit.” So, with the pool pump in med pump pressure the heater shows b0 all the time. Doesn’t sound correct.

We’ll share your comment with our tech team.

Hi, I have the L0 indicator again, after a couple of months without this issue it seems is coming back. I did many things like a replacement of the the 2 board card inside the heater, the replacement of the Front Panel and the Ignitor. But after 2 months working fine now is coming back the L0 error. I don't know what else can be done to solve this problem.

Having the same issue. Heater will run while pool pump is priming and then go to LO and not turn back on. Tried increasing to highest speed of pump and still getting LO. Had the screen and dashboard replaced last year.

hello

my hayward heater works when the pump is on but once the pump is off the service light turns on and I get LO on the screen. is this normal?

It did not used to do that.

thanks

Following as we have the same issue LO code on H400.

Just had our heater moved and pump replaced. Now have a Pentair VS pump, and after first start up this season, LO message and Service light.

I have backwashes twice, and still get the LO message...

how can I reset the Limit String Open and lock out...I don’t want to start changing 8 different switches inside!

Im gett a lo code on new heater. i have a sand filter and it is clean

My hayward h serie natural gas 250btu is 2 days old ,only use every day for 3 hour for 19k pool and bypass it most of the day, seen working good , remind is stand by ,then LO code appear when I empty the water on the heater exchanger using the valve pressure on heater .i know it's inducted by me due to water in exchanger without move can come corrosive.yesterday it was working and set to 82 temp ..it just turn off without reach such temp ....i came and set it up higher 85 turn on and reach 88 ,,stop and i notice temp display was counting down 87...86 .i mean it's normal it work as an air conditioning.?and what I'm doing to remove the water from exchanger after used Is ok .thx

Hi. my heater turns back on with LO signal even when i turn it off. ill turn it off. then i hear clicking sounds, and then it turns back on to say LO.

I noticed HU-115683754 also got a new Pentair VS pool pump. I have just installed one, cleaned the filter(2X) by the way. Clean the skimmer baskets and the pump basket, turn pump on, wait for it to totally fill filter, removed the air from the filter, and wait 2-3 mins to turn on heater. Heater runs for over an hour, then goes into 'LO' mode and Service light comes on. If I stop heater, stop pool pump, remove the pump basket and totally clean it and start everything, heater runs for about an hour. The pump basket is not full but the outlet part of the basket gets clogged with debris and it looks as the GPM drops also but not below what filter and heater require to run. Could it be it is this pump basket is just getting clogged? Also installed a flow meter which averages around 50GPM/4.9 velocity leaving the pump.

LO code. Try backwash then recirculate. If neither works this is what i did next. Test the Presurre switch. Disconnect two connectors attach wire between and see if code dissapears if it does then you need to replace pressure switch. Very easy to do.