Sta-Rite SR333NA Max E Therm Pool Heater

[drewgost]

I have a loud high pitch whistling sound after the heater fires up, for the time being I put a rock in front of the air intake to equalize the balance of air and natural gas. The high pitch sound stopped and the heater is working fine heating the pool.
I would like to fix this properly. ajw22 suggested getting a manometer to check the pressure. Any thoughts on how to tackle this job would be much appreciated.

See video for the issue.

 

[ajw22]

How old is the heater?

When did the problem begin?

How long was the heater operating normally before the whistling began?

What other NG appliances do you have?

Everything points to restricted gas flow. My WAG is rust in an old iron gas line. Maybe a malfunctioning gas meter.

Show us pics of the heater gas line connection and your house gas meter.

If you are not experienced working around a gas line bring in a gas technician to look at it.

 

[drewgost]

Hi ajw22 and thanks for the reply.
Heater is 2017, problem started in June 2022, Gas stove, furnace.
I noticed they did not put a sediment trap on the line as required in the manual for this heater.
I have a large gas meter I was told by the gas company it could run everything in my house and my neighbor's house. (I had them swap out the small one for the larger one)
As far as a gas technician, would you call the plumber that installed the line?

Thanks,

Drew

 

[drewgost]

a better picture

 

[ajw22]

Lack of a sediment trap can be part of the problem. Sediment in the gas line needs someplace to go and not clog the heater gas valve.

A plumber who does gas work would do. Not sure I would use the guy who left out the sediment trap.

While you say the heater is working fine I doubt you are getting the rated BTU heating with restricted gas and air.

 

[drewgost]

Meter

 

[ajw22]

Check that the correct sizes of pipe were used - 3/4" and 1".

 

[1poolman1]

I have a loud high pitch whistling sound after the heater fires up, for the time being I put a rock in front of the air intake to equalize the balance of air and natural gas. The high pitch sound stopped and the heater is working fine heating the pool.
I would like to fix this properly. ajw22 suggested getting a manometer to check the pressure. Any thoughts on how to tackle this job would be much appreciated.

See video for the issue.

Was the air orifice changed? There are different sizes for all of the Pentair/StaRite models. A 400K orifice will do that.

 

[gkw4815]

Any chance the buried gas line between your heater and gas meter is leaking?

We had this issue (failed buried gas polyline coupling, right at 100 ft from the gas meter). Initially we noticed a faint gas small from the buried line, and eventually the pool heater wouldn't fire. Turns out that as gas was leaking out, groundwater was leaking in, and eventually a slug of water blocked the gas flow. Repairing the leak and blowing the water out of the gas line solved the issue.

 

[drewgost]

Hi guys thanks for the reply's. I don't think there is a smell of gas anywhere but I will check, as far as the "Air Orifice" I don't know what that is but I will look into it.
Thanks again for everyone's thoughts
Ill post when it is resolved.

 

[1poolman1]

Hi guys thanks for the reply's. I don't think there is a smell of gas anywhere but I will check, as far as the "Air Orifice" I don't know what that is but I will look into it.
Thanks again for everyone's thoughts
Ill post when it is resolved.

Air orifice is the plastic part you are blocking. The larger the BTU of the heater the larger the hole at the other end at the fan.

 

[drewgost]

thanks 1poolman1 the orifice was not changed as far as I know. I will ask the pool company that opens the pool.