Pentair Mastertemp 250K BTU heater loud humming

[JamesW]

Maybe remove the front panel and show a video of the heater startup.

Does the sound start as soon as the fan comes on before the heater actually fires or does the sound only start when the heater fires?

Can you show the heater air intake from the outside of the building?

Maybe something got sucked into the air intake?

Is the air intake screened to prevent debris from getting sucked in?

 

[JamesW]

Yes permit, final inspection has not been done.

The final inspection needs to be completed before the heater is used.

 

[ajw22]

When you remove the cover of the heater the sound seems to be clearly coming from the boiler and everything else is vibrating from that.

If you turn the gas valve down a bit, the sound goes away

Do you have sufficient water flow?

Sounds from the boiler can indicate you have boiling water and steam being created which is usually due to insufficient water flow.

Turning down the gas turns down the heat which stops the boiling.

 

[Newbieone]

Is the installer a qualified gas contractor with the correct contractor's license?

Can you show the entire flue inside and outside?

I would see what Pentair has to say.

Is the installer a qualified gas contractor with the correct contractor's license?

Can you show the entire flue inside and outside?

I would see what Pentair has to say.

The contractor has installed a lot of pools and has been doing this for years. Gas line was installed by our plumbing contractor.

 

[Newbieone]

Can you show the gas line?

Is there a regulator on the line near the heater?

This is the second regulator. The pool contractor says the noise became louder.

 

[JamesW]

It sounds like it's fan related.

Does the sound start right when the heater fan comes on or does it only start when the heater actually fires?

You should be careful not to do anything that could void the warranty.

If the original contractor refuses to make it right, contact Pentair to get their opinion and maybe a recommendation for a qualified professional.

Get the final inspection to make sure that it's up to code. Ask the inspector for their opinion about the sound.

In my opinion, it's not right, but I don't know exactly what is the problem.

 

[Newbieone]

Is that the sound when it's running?

Can you show a longer video including the startup and the display?

We are out of town now. We will post that when we return. The sound when it starts up is normal and quiet for a minute or two after the burner ignites. Then this sound starts up. It gets louder as it runs longer. We didn't notice the sound for the first week the heater was running and I believe it was normal. We were in the room with the heater while it was running, so I am quite confident of this.

 

[JamesW]

Maybe something got sucked into the air intake?

I would leave it off until it can be inspected and fixed by a qualified professional.

 

[Newbieone]

Maybe remove the front panel and show a video of the heater startup.

Does the sound start as soon as the fan comes on before the heater actually fires or does the sound only start when the heater fires?

Can you show the heater air intake from the outside of the building?

Maybe something got sucked into the air intake?

Is the air intake screened to prevent debris from getting sucked in?

We will post pictures of the other things when we return home.

 

[Newbieone]

It sounds like it's fan related.

Does the sound start right when the heater fan comes on or does it only start when the heater actually fires?

You should be careful not to do anything that could void the warranty.

If the original contractor refuses to make it right, contact Pentair to get their opinion and maybe a recommendation for a qualified professional.

Get the final inspection to make sure that it's up to code. Ask the inspector for their opinion about the sound.

In my opinion, it's not right, but I don't know exactly what is the problem.

The contractor says the gas line is not supplying enough gas. He doesn't want to contact Pentair because they will void the warranty. This sounds suspicious to me. The same line has run the 275,000 btu Raypack boiler for the driveway heater for 12 years with no issues. He texted these pictures to me, which I can't interpret. It does not make sense to me when you close the gas valve slightly to the position shown here, the sound goes away and the boiler appears to operate normally.

 

[JamesW]

Based on the pictures, there is a problem with the gas supply.

There will be a valve near the main gas meter. Is that valve completely open?

 

[JamesW]

What doesn't make sense is that if the installer knew that there was a problem with the gas supply, why didn't they just tell you instead of saying it was fine?

 

[JamesW]

The heater should not have been allowed to run with the gas pressure being known to be too low.

The heat exchanger might be sooted and clogged.

You need to have the plumber figure out why the gas pressure is too low during operation.

Fixing the gas pressure might not fix the problem if the heat exchanger is clogged.

You might have to clean the heat exchanger or replace the heater.

 

[JamesW]

The heater requires a gas supply of not less than 4" (10.2 cm) wc and not more than 14" (35.6 cm) wc.

Gas supply pressures outside of this range may result in improper burner operation.

A minimum flowing or dynamic inlet pressure (while the heater is running) of 4" (10.2cm) wc is required to maintain input rating with no more than a 2” pressure drop between static and dynamic.

Here is what the manual says about the inlet gas pressure.

Assuming the pressure shown is the inlet gas pressure and not the manifold gas pressure, you can see that the pressure is too low.

Verify that the pressure shown in the pictures is the inlet gas pressure.

 

[borjis]

I wouldn't talk to the installer any more if this was my equipment. If he voided the warranty somehow, thats on him.
I'd only talk to Pentair from here on out.
He's going to injure or kill someone w that work ethic.

 

[Newbieone]

Any thoughts on the Raypack 275,00 btu boiler working fine for 12 years? That is the odd man out in my mind. Same gas supply. Raypack is only 9 feet away as the crow flies.

 

[JamesW]

Are you sure that all of the valves are open?

Sometimes the gas line corrodes and gets clogged up.

You need to have the plumber figure out what's wrong with the line.

Maybe the gas pressure slowly kept falling until it caused or accelerated the failure of the old heater.

 

[JamesW]

It looks like the static pressure is fine.

The problem is that when the heater starts, pressure drops way down, which indicates that the line is probably seriously clogged or restricted somewhere.

It's the same issue as in the video I linked to.

The static is good. When the heater starts, the pressure should not drop more than 2 inches wc from the static pressure and the dynamic pressure should not go below 4 inches wc.

 

[Newbieone]

Are you sure that all of the valves are open?

Sometimes the gas line corrodes and gets clogged up.

You need to have the plumber figure out what's wrong with the line.

Maybe the gas pressure slowly kept falling until it caused or accelerated the failure of the old heater.

New pool with new heater (Pentair). "Old" heater is our current RayPack heater for our heated driveway. Still runs as well as it did 12 years ago. They took a branch off the RayPack line just before the regulator and ran it to the new Pentair Heater for the newly installed pool.

 

[Newbieone]

It looks like the static pressure is fine.

The problem is that when the heater starts, pressure drops way down, which indicates that the line is probably seriously clogged or restricted somewhere.

It's the same issue as in the video I linked to.

The static is good. When the heater starts, the pressure should not drop more than 2 inches wc from the static pressure and the dynamic pressure should not go below 4 inches wc.

THANKS!!!!! We will check the line between the two heaters. I noticed where it branched off it was heading AWAY from the new heater and then made a U turn to go back towards it. I'm not sure why that was done, but that would be a likely spot for a restriction. We really appreciate your expertise, and time!