Howling Jandy JXI heater

[flynwill]

I have a new (installed in October) Jandy heater that is making a loud Howl or whine. The symptoms are very similar to the issue described in this posting:

https://www.troublefreepool.com/threads/jandy-jxi-heater-whine.224775.

The noise starts a few seconds after the burner lights.
The burner often takes multiple tries to light (you can see the igniter heat up, hear the gas come on and then shut off again the first time it tries).
Once the incoming water reaches about 90F the noise goes away (observed while heating the spa).

The heater is under warranty, and so far the technicians have tried:
Replacing the blower
Replacing the Gas Valve
Replacing the Thermal Control Valve.
Replacing the integrated bypass mechanism.
We have also had the Gas company out to check pressures, and find that is well with in spec (9.7 in WC static, 7.5" wc when the heater is running).

The heater is in a shed and is vented by about 6 feet and two 90 degree elbows of 4" Cat III flue so it was thought that the flue might be an issue, however we have tested disconnecting the flue at the heater and it make the same noise.

Any thought from the TFP collective?

 

[ajw22]

What speed are you running the pump when the heater is on?

Anyone put a stethoscope on various parts of the heater to hear if the whine is from the burner, air blower, water pipes, or gas line? Some talented folks can put their ear to a screwdriver.

 

[flynwill]

Nominally 2300, but I actually tested different speeds from the minimum that would allow it to light (about 1800) to 3000 RPM, with pretty much the same result.

No, no-one has tried the stethoscope or long screwdriver trick, that might be something to suggest. When the technician left today he was going to have one of his associates come take a look. I also suggested that the give Jandy a call which hopefully they will do. He also mentioned that if all else fails they would get Jandy to just put in a whole new unit.

 

[ajw22]

Make a warranty claim with Jandy and make it their problem.

A new unit was a thought.

 

[flynwill]

Posting a followup for anyone who might have this same symptoms.

The local service company decided to get a "second opinion" and ask "Sam" to come take a look. Well Sam replaced the Thermal Regulator Valve (for the second tiime) and that cured the issue.