New Pentair Mastertemp 125 Heater Installation - Squeals like a pig when heating...

[JoyfulNoise]

Then maybe it’s worth checking the TR at some point to ensure that it's opening and closing properly and that there isn't some debris or defect that causes it to crack open a bit?

 

[JamesW]

You can see the bypass disc here.

It looks ok.

View attachment 380011
If you push down on the top of the spring, the disc should move down and it will be more obvious.

The bypass comes apart, so be careful not to push on the spring in a way that could make it come apart.
View attachment 380013



Here is what the normal exhaust temperature should be:

• Below 250 degrees...very low
• 250 to 290 ..................low
• 290 to 350.................acceptable
• 350 to 480 ..................high
• Above 480...................error/shutdown.

Note: HD models can be up to 75 degrees higher. HD models use a cupro nickel exchanger and the efficiency is slightly lower resulting in less heat transfer and more waste heat.

Your heater is not a HD model, so the stack temperature is too high.

View attachment 380010
This part will unscrew if you need to get a better look at the internal bypass.

Look into the inlet to see if you can see the manifold bypass.

Check the stack flue temperature.

Maybe check the thermal regulator to see if it looks ok and test it to see if it is opening correctly.

 

[ps0303]

Awesome!! Glad you got the unit working. Wow, obnoxious of Pentair to treat you that way … companies have no common sense nowadays when it comes to building up good will with customers. Sure, you did a self install and you own it, but they can clearly see from the paper trail of service calls that you were willing to do all the hard work and all you asked for was a little help. And they decided to treat you like Crud. That orifice part would cost them nothing to throw your way for free but, by standing their ground on their “rules”, they’ve potentially cost themselves a lot of future earnings … businesses run by people with no business sense whatsoever …

I suspect partial boiling of the water inside the heat exchanger likely caused vibrations that emanated as the “screeching” noise. A vigorous bool would sound like banging and hammering but a very mild boil could cause vibrations of the metal fins. Given their right spacing, higher pitched screeching is totally possible.

Companies are tired of wasting time and money for DIY installs. BTW, I wouldn't be surprised if more companies stop allowing their units to be sold on the internet. It's not like buying a refrigerator and plugging it in to power. I can't begin to tell you the number of times a homeowner installed a unit and their install was wrong and caused issues. Companies want licensed installers doing this work. I will also add, I read this post and saw some of the suggestions provided by people and they were completely out in left field. Having a ordinary homeowner check things like gas pressure is crazy. Most don't even have the correct tools to check any of this.

In this case and any case where a heater "whines" or "moans" when it's fired up, it is usually 99% a water flow issue.

While I do acknowledge that many here know some things about these units however, having a trained licensed person looking at it is the best approach.

 

[JamesW]

One problem is that most Pool Service people are not licensed to handle gas and many gas qualified contractors don’t want to work on “Pool” equipment.

Most states provide online license checks to see if a business or company is licensed to do gas contractor work.

A property owner should verify the license of the business and the license of the service technician.

The work does require some professional expertise, but it’s not rocket surgery.

Some people have the skill to work on things like this and some people don’t.

People have to decide for themselves if they are qualified to do the work on their own equipment.

The person who goes hands on with the job has to take responsibility for the work.

A person who is not licensed should not work on other people’s equipment.

 

[JoyfulNoise]

Perhaps Pentair will go the “full Jandy” and “leave the internet” … not an especially smart business decision in my opinion. Businesses that serve the public need to serve all levels of the public if they decide they want to sell their products in the retail space. If they don’t want that responsibility, then they shouldn’t advertise themselves as such and only do business to business transactions (like Grainger Supply Company) and then require proof of license when selling their products. Doing so will ensure they don’t have to deal with the “annoying customer” …

As for DIY, for some, it’s the only option. Not everyone lives in an area that has licensed trades people available in every field and some (like me) live in areas where the trades people can be very sketchy. They advertise themselves as being “license, bonded and insured” but then the guy that shows up at your front door to do the job is some Home Depot parking lot dweller that the “licensed guy” sent over instead of doing the job himself. Around here, that’s a very common business model where you get charged for the “professional” but the guy doing the work is unlicensed/unskilled. To me, that’s a bait & switch. I have dealt with this over and over and over again and it’s extremely frustrating as the consumer to pay for the professional when all you get is the hack and a promise that the pro will fix any mistakes made. Sorry if that sounds entitled, but as the guy laying out the huge sums of money for the job, I expect a professional to do the job. If I wanted a Home Depot hack, I’d go there myself and pay the guy.

At the end of the day this thread had nothing to do with the install, it was a problem with a valve setting and water flow. I’m glad the professional friend of the OP was able to help him out so he didn’t have to waste lots of money and time. And, as is always appreciated, I have learned something new that will help me out in the future if I decide to DIY my own heater install ….