Pentair Mastertemp 250 Natural Gas

[jsherwin]

Greeting all- I am fairly new to pool ownership and have found this site and all the guru's very helpful. I am located in beautiful Austin, Texas and just completed a new Heater install.
After getting gas line in place tested / permitted heater went into service last night. I noticed that it cut off once the temp reached 79*.
We had a brisk starting temp of 66* an as able to get the water up to 79 when it shut off.
I did the heater install.
Gas line and sediment trap et al was done by plumber.
I pulled the top and located the HLS led when the heater shut off.
I did notice that the heater will turn back on after a bit of time but it basically cycles the service heater with a HLS led on rear panel.

Is it possible the High Limit switch failed in less than 24 hrs?

 

[ps0303]

Is this a brand new out of the box heater?

 

[jsherwin]

Yes, purchased brand new less then 2 weeks ago via Amazon.

 

[JamesW]

Any chance you got the in/out backwards?

 

[jsherwin]

Well, anything is possible but I don't think so. I did verify the warmer water coming from the jets in the pool.
Set up is Pump to filter> in Heater > out to salt cell to pool

 

[ps0303]

Sounds like you have it piped correctly. How about a picture of the setup? A new unit obviously shouldn't be doing this but it does have the sound like it's piped backwards. Th IN is the upper pipe and the return is the lower one.

 

[jsherwin]

Yes- In is upper and return is lower. In from Pump to filter to heater and out to chlorine generator to pool. Will post pics in the morning when we have daylight. I just spoke to Pentiar and they were very helpful. Waiting to see what if any recourse I have.

 

[JamesW]

What is the flow rate through the heater?

Is there a bypass on the heater?

 

[jsherwin]

I do not have the flow rate info- any info on how to check would be appreciated. Also, no bypass currently in place.

 

[bongardjm]

Had the same issue with my Mastertemp 300 heater. It would heat up to 90 and then cycle on/off. Turned out to be this part -->
Amazon.com : Pentair 77707-0010 Thermal Regulator Replacement Kit Pool and Spa Heater : Portable Outdoor Heating : Patio, Lawn Garden

The Thermo regulators in these heaters are very sensitive (according to Pentair) on alkalinity levels. Too low and will corrode the thermo regulators making them stick at a certain temp. Once stuck the heater thinks it is overheating and "turns off". Sounds like yours is new. Look between ther in/out flow connections there is a black screw like mechanism holding it in . Use the blade of a screwdriver to twist it off and look at the regulator. if appears rusty that couls be your problem.

- - - Updated - - -

Also if you read the reviews of the part on Amazon it sounds like a lot of people have your same issue with their heaters

 

[jsherwin]

Thanks- I have ordered a new High Limit switch and a Thermo Regulator and will be replacing as soon as they arrive. Will do one at a time to see which actually fixes my issue.

 

[ps0303]

What made you think these two parts need to be replaced? Also, since this is a band new unit, did you even try to call to see if you could get someone out and maybe they will honor the warranty?

If you just installed the heater and it's new, you should not be replacing the thermo regulator. In fact you could have at least tested the regulator see if it is operational. I would NOT just start replacing parts on a new heater without a truly diagnosing the problem.

 

[jsherwin]

Great questions. The code says HLS - thats what made me think the HLS is bad. Perhaps HLS is a indication of another issue?

Yes, I do have a warranty service call coming Monday.

 

[jsherwin]

I am thinking it is not getting enough flow and getting to hot.

 

[JamesW]

You have a line teed off after the filter feeding the booster pump. That's taking water flow from the heater. Put the booster feed after the heater.

 

[ps0303]

A picture says a 1000 words. Either you put the booster pump pipe in after the heater as JamesW says or you push the handle down to shut the valve you have going to the pump. Either way, it's a water flow issue.

This is why I like to ask for pictures in some cases. You can't truly know what's going on in some cases unless you look at it.

 

[jsherwin]

On the pipe to booster- where do I need to re-route or re-pipe ... on the out of the heater? Before or after salt cell? Does it matter if booster gets heated water?

I really appreciate all the help- and so will all my nieces and nephews this coming weekend!

And please pardon my ignorance

 

[Pool Clown]

Can anyone tell me what else is wrong in that picture with respect to the heater?

 

[jsherwin]

Can anyone tell me what else is wrong in that picture with respect to the heater?

- As previously stated- I am new to pool ownership and trying to figure things out. Constructive criticism would be appreciated.

 

[ps0303]

Pool Clown is just wanting to see if others see something else. Nothing against you. I see plenty of DIY pool repairs and various installs.

I see several things like the DWV 90 used on the piping, and no bypass plumbed into the piping, and the yellow flex gas line. I see lots of flex lines being used. A homeowner knows it's used on their gas stove or dyer so it's OK on a heater. Really it's not OK to use on this appliance. The other thing is, it's going to be a pain in the arse to work on that thing.