Pentair Mastertemp 250 pool heater “Not heating” problem solved(Bad AGS sensor) ....Here’s how I...!

Automatic Gas Shutoff sensor “AGS” link to order through Amazon below:
www.amazon.com/gp/product/B00...
Today I tackled a problem I’ve been wanting to fix for sometime now. My pentair Mastertemp 250 pool heater would start up and not heat and than prematurely shut down. Here’s how I fixed the problem! Thanks for watching and as always if this video has help you out please hit that thumbs up button.
Disclaimer: I am no professional, nor claim to be. Everything is at your own risk! Enjoy and be safe around live wiring.
Jan 22, 2021

[@2006JeepLimited57L]

Update: If this video has helped you out in any way and you would like to drop me a donation.. The appreciation would really go a long way in helping me to keep creating! As always, thank you! Venmo> @Ruben-CastJr

[@polyscroll]

Thanks man! Replacing the AGS sensor solved my problem as well. Well done!

[@donpistos8356]

Thank you for the video, you just saved me 180 bucks!! Bought the part myself Fixed the problem in 5 minutes 😁thank you

[@2006JeepLimited57L]

Awesome!

[@TheRealPhilipK]

Thanks! Really appreciate your footage! You helped me fix my pool heater!

[@syedullah613]

Thanks To you & youtube I just jumped the wires and it fired right up. Thanks

[@2006JeepLimited57L]

Awesome!

[@TheDigitalGangsta]

Aaayyyee UTI Alumni 🤘🏽I went to sac school, I work for Ford and have a pool service business 😁😤

[@alanwherrera9017]

Thank you very much. Great video and awesome information

[@porkchopwalkedtomaine3853]

Thanks man great video

[@bendelaney7944]

Thx man... I got one with a 400 model. Great video 👍

[@shortedout]

Thank you!!! Fixed!!!

[@FLYBOY123456789]

Excellent tip - just checked mine and heard the beeeeeep...therefore, mine is a different problem. Won't stay lit for more than an hour...oh well...

[@2006JeepLimited57L]

This “AGS sensor” fixed the problem and the Pool heater still working great! 03/07/21

[@alexnacca6351]

Omg thank you so much for this! Same issue for me and my pool is only 3 years old

[@adnanshaben8889]

Awesome thank you, worked like a charm

[@obeliskgroup5714]

Thanks for the video. Mine is Jandy LX with same problem. Will see and try to fix it. I'll update you after fixing/ trying to fix it

[@ericstout8249]

Thanks for the video. That was my problem. Hopefully you get a kickback from the Amazon link. 👍

[@kw57rx8dr.9]

You know I appreciate DIYeR's I'm one myself too, but you like to get paid and earn a living off of your chosen specialty or trade too don't you? So while you may think it expensive, consider all that you're paying for someone else's training. They come to your house and work in the hottest as you can see cramped conditions in many cases, they have overhead of vehicle costs, insurance, gas, tires etc. and they have multiple specialties and years of training in chemicals, plumbing, electrical, gas of both kinds, heat pumps, automation etc. across a wide range of trades that very few other trades have. Pool repair techs deserve more respect than they get. So while the part may have seemed expensive at the pool store, consider their overhead and immediate availability in many cases and THAT's what you're paying for and if you do the basic math you'll see it's not as expensive as you think it is. Stores and service companies can't compete with internet prices, margins are already paper thin but they're not ripping you off, we all need income. In any case, thanks for the video. FYI just use a blade fuse for the jumper for various wires and that way if it does have another issue it'll also blow the fuse potentially instead of doing more harm but it is very convenient to use it for a jumper instead of manufacturing a wire for the job.

[@venanciomarquez1863]

Thank you for your good video. Have a nice day. Amigo.

[@wk9858]

Thanks brother I had the same problem

[@2006JeepLimited57L]

Anytime!

[@2006JeepLimited57L]

For anyone with the same problem as me, hope this helped!

[@markhudgins1280]

Mine is starting and burner ignites. Then shuts off like yours. AGS LED is lit up as well. Any thoughts? Checked AGS sensor for continuity and it’s fine. Bypassed AGS and it does the same thing.

[@prakashatgmail]

Great Video, Thanks. I have a Master Temp 250 as well. It heats well for a few hours and then shuts off. Same time the water flow from the pool to the pump reduces significantly too. So much so that the skimmer basket floats on top. I have cleaned the lines and filter cartridges thoroughly. So there are no blockages. Also, when the heater is off, everything runs smoothly without any issues. Filter pressure reads 6 PSI before heater is started and 10 after heater is started. When heater shuts off on its own, filter pressure drops to 2. Not sure if heater shuts of due to the pressure drip or vice versa. Why would the pressure drop on its own? Especially given how smoothly everything runs when the heater is off. Any input from you will be highly appreciated. Thanks

[@2006JeepLimited57L]

Your heater will shut down if it does not detect ample water flow. When this happens the pressure switch will trip and activate the PS led light on the back of your circuit board and thus shutdown the heating unit down to prevent damage. One question, when was the last time you bought new filters?

[@officerkrupke4966]

Your filter pressure is lower than normal which points to a pump issue. I would first check if I could reach with my hand, with pump basket lid and strainer removed, and feel inside pump inlet for any debris that may be lodged in there. Otherwise I would open pump housing and inspect pump impeller for debris. What you describe sounds like when you first start heater, most flow is still bypassing heater via internal bypass valve while temperature regulator is closed due to cold water. As heater starts working the regulator opens up, allowing water to pass thru heater which is more resistance to flow, causing your filter pressure to increase. Heater has barely enough flow thru it to keep from tripping on high temp, which it does trip after it warms water up a bit more.

[@fliktrax]

Great Video unfortunately did not solve my problem. My pentair 250 cycles through startup process and locks out after third try but I'm smelling a bit of gas after every time it clicks to try and fire. I thought it was the HSI (hot surface igniter) and I've replaced that a couple times already. But when I feel down around the igniter it feels damn hot so I just can't imagine why it is not firing. My membrane pad is working just fine and when I look at the back of my control board I see no led errors on AFS AGS SFS ect. All looks good and membrane is showing no errors. Utterly frustrating because the last time this thing fired it took a lot longer than usual and then finally I felt a little hot air coming and then it fired. Since then It just won't fire and all electronics seems to be acting normal. Do these heaters have problems firing in very cold temps because I noticed it didn't want to fire in the morning but would eventually fire later on in the afternoon after it got a bit warmer but now that isn't happening either. Could it be condensation o the HSI or something else. may be he HSI is bad even though it is getting hot it's not getting hot enough. Just weird because I have two of them now since they go bad so often but both are doing the same thing. They get hot but heater still wont fire. Any thoughts you have would be welcome you have obviously done your homework on the pentair 250. I even tried jumping the leads on the AGS like you did and it wouldn't fire.

[@gonzogear]

did you ever find out what the issue was? and how did you fix it? sounds a lot like what I have going on now. thank you

[@craigsmythe_407]

Where did u order ur ags sensor.. I can’t find a provider who will sell

[@jenmc847]

Thanks for the video. Very helpful.

[@2006JeepLimited57L]

Still good 2 go 20 months later 8/17/22

[@debbiejones573]

What would it indicate if the heater came in with no problems in the am but after 7 pm it will not fire up? Sounds like it’s on a timer.. right? But, there is no timer set… any ideas?

[@officerkrupke4966]

If you have a variable speed pump and your pump speed is set to different speeds on different schedules, you may be running it too slow in the evening hours causing the heater to trip out on low flow via the heaters pressure sensor.

[@debbiejones573]

@@officerkrupke4966 Dear Sir! Thank you for taking time to answer! It makes perfect sense to me, what you shared! I will check into this!

[@Barewake2]

Did yours trip your breaker or just the unit would shut off?

[@2006JeepLimited57L]

No. It did not trip the breaker, but the display on the mastertemp 250 would freeze on me and stay on even if I tried to press the power button off. The only remedy for me was to flip the breaker and reset the unit to power it off until i could fix the unit.

[@officerkrupke4966]

@@2006JeepLimited57L Thats what happens when the Fenwal shuts the heater off on lock out. Which happens when it gets a signal that the ags is in open position. Buttons wont work until you remove power to reset it. Safety feature.

[@mattschissler9389]

I have a pentair 300 but looks very similar. I have the same problem, blower comes on but heater does not fire on. It will “click” but does not ignite. After a minute the “service heater” light comes on. I checked the board but no error lights come on. I checked the 1 item you replaced but it was “closed” on startup. Any other suggestions? Thx!

[@2006JeepLimited57L]

Hi, follow the flow chart I provided in the link for your pentair 300. It will help lead you in the right direction. Based on what your telling me and if I didn’t miss anything I followed it out and ended up somewhere around “heater will not fire C and D of the flow chart” . You might have a possible gas flow issue, or igniter problem in your unit. Both can be verified. The first can be verified by checking the meter for movement about 30 seconds after calling for heat. The second can be verified by checking for voltage across the igniter leads. blog.intheswim.com/pentair-pool-heater-troubleshooting-guide/ Let me know if this chart helps you?

[@2006JeepLimited57L]

One other thing, make sure you are running a clean filter as sometimes flow will prevent the burner from firing. Just in case...always gotta work from the easiest fix on up.

[@Gmoney1019]

@@2006JeepLimited57L if you were to have a flow issue the "service system" on the keypad will come up.

[@2006JeepLimited57L]

@@Gmoney1019 My board kept freezing up on me. I developed a mistrust for it at one point after hearing lots of bad things about dysfunctional boards on some of the pool forums. Im just glad the sensor fixed the abundance of issues I was having.

[@officerkrupke4966]

@@2006JeepLimited57L Membrane pad locks out after third try at lighting for safety. Need to turn power off than on to reset.

[@allonfeig5149]

Changed the AGS but the heater still shots off. What else can be the problem the AGS light still comes back on

[@2006JeepLimited57L]

Kind of hard to say without being there to look but Here you go, you will find this very helpful. ----> you can view the troubleshooting and flow charts to guide yourself for your pentair heater. Link below: Troubleshooting starts on page 39 with Ags light troubleshooting starting on page 43 www.pooltek.com/wp-content/uploads/2017/02/Heater-PentairMastertemp.pdf

[@allonfeig5149]

@@2006JeepLimited57L Ty

[@keithdantonio680]

I have nothing but problems with mine I would love to be able to talk to you for 10 minutes I have a problem now that I cannot solve