Gas supply to heater too rich

[davidgelb]

Hi all,

I have a newly installed Pentair Mastertemp 300 that has a high pitch whistle intermittently. I understand that this is an indication that the flame is too rich.

After the heater was installed, the gas company installed a larger meter feeding the house...went from a 200k btu meter to a 425k btu meter.

Can anyone give me some insight as to how to test the supply line gas pressure with a manometer? Is there a test port in the Mastertemp? Also, does anyone know the recommended W.C. reading for a natural gas 300k btu Mastertemp?

Thank you in advance for your help!!

-David

 

[ps0303]

If this unit is NEW, it's under warranty and I would call out a Pentair warranty repair company. Messing with the unit you risk voiding your warranty. You have at least a two year warranty on this unit, why risk it.

The high pitched sound means the unit is drawing in too much air causing the whistling sound.

 

[danpik]

The manual for the heater should have the specifications for gas flow and pressure in it. I doubt that the meter change increased the pressure enough to cause a significant richening of the air fuel mixture. Going to a bigger flow rate does not change pressure, and gas companies are pretty anal about their meters and regulators being in proper calibration

 

[davidgelb]

It tested just under 10 w.c., so I should be OK. A tech at pentair said I need to be at 12 or under. If I notice the whistling again, I will have pentair come out to check it out.

Thanks!

-David

 

[CPSScott]

Did the gas man use flex line going into the heater? I've seen it before, the line installer hard pipes it from the meter/regulator and stops about 2' short of the heater and reduces the line down with the yellow flex line bottlenecking the supply. It should always be hard piped with a union outside the heater.

 

[davidgelb]

No, it is hard piped all the way to the heater - no flex. I am going to call Pentair to come out and address the whistling and occasional CHECK HEATER light. It's under warranty - might as well let them deal with it!

I will let you know what I find.

Thanks!

 

[Pool Clown]

Was that 10" water column while the heater was running? Or at rest? The critical measurement is while running. Water column spec should be on sticker attached to metal box that elec connection is made to. Whistle is from pressure, not mix. New meter has new regulator. It doesn't happen often, but not impossible for regulator to be out of calibration.