Brand New Rheem making whistling noise

Problems related to residential installations.

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Brand New Rheem making whistling noise

Post by ToneG2424 » Mon Jun 09, 2014 11:58 pm

Recently I just got a brand new furnace, condenser, coil, the works. Everything works great except for a whistling noise when the unit is continuously off for a few hours. The HVAC professional who installed the unit said that I need another return vent installed as there was not enough air flow into the blower with this brand new unit. He came across this solution because when he removed the bottom door covering the blower, which allowed for my air to enter the unit, the whistling went away. Since another regular sized intake was installed the same issue has followed to my disappointment. On hot days when the unit shuts on and off throughout the day, the whistling never comes on. Only surfaces when unit doesn't run for about 8+ hours. I feel there is some sort of pressure that builds up causing whistling. I have a 16x15x5 sized filter in there but I ran system without filter in and whistling still surfaced. Any ideas would be great.

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- Brand New Rheem making whistling noise

Post by Freon » Sat Jun 21, 2014 2:17 pm

I am confused by this statement."Everything works great except for a whistling noise when the unit is continuously off for a few hours."

Are you saying after the system is off for a few hours and then it starts back up then you hear the whistling? I am assuming the whistling happens when the blower is operating.

Is this whistling happening in heating or cooling mode? If you go to the thermostat and change the FAN setting from AUTO to ON (turns on only the blower) does it whistle?

What is the make/model of the furnace and condenser. Whistling is usually due to high velocity air flow due to inadequate ducting. It could be either the return or supply ducting. Try and locate where you hear the whistling the loudest. Your system needs a certain amount of airflow to operate safely and efficiently. The make and model numbers will tell us what airflow you need and then we can see if your ducting is sufficient to handle that airflow.

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- Brand New Rheem making whistling noise

Post by Hunterman01 » Wed Jul 09, 2014 7:00 pm

I have a friend that installed a brand new unit like you did but my friend also installed the duct work and had a balanced system as in good static pressures,velocity to cfm ratios etc.,,and still had a unit that would whistle but only when the home owner would close her windows and bedroom door at night? so my friend went to the supplier and they didnt believe him after much convincing and them trying to say maybe he didnt install it right he finally convinced a rep. to come out and once showing them how he installed it correctly they gave him a new unit,which fixed the problem.Good luck!

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