Help! I am in serious trouble!

[WorryWart]

Tinknocker,

Dumb question #492: Where is the condensate pump? Is that the pump on the floor in front of the blower? They didn't replace that--was here when the A.C was. Maybe again they didn't feel like doing the extra work to rewire?

[Shophound]

Hmmmmm...that's interesting. Is there anyway to insulate the ductwork to produce the same result? I would be concerned about (a) cost and (b) durability of the flex.

Is all of your ductwork of sheet metal construction now?

Flex duct must be sized properly and installed tightly. You would also not need to replace all of the metal ductwork, only the last six feet or so to each supply vent in each room. That's what I did at my FIL's house, for the most part, except the one section of trunk I replaced with a length of flex, as it was easier than doing each supply vent. It worked just fine.

Here was the full situation that made my FIL's house unbearable until the modifications were made:

• The construction of the air handler has the blower wheel and motor above the indoor coil.
• The plenum above the air handler going into the attic is insulated on the outside, not the inside. There is no insulation on the inside to attenuate noise. With this type of duct design (radial), exterior insulation on the plenum is normal and expected.
• All of the ducts feeding out from the centralized supply plenum were round metal duct, externally insulated. Nothing to dampen both blower and duct noise.
• Supply grills were stamped steel variety, which are restrictive and can create a "rushing" sound when too much air is forced through the vanes.
• The nature of the blower wheel described in my last post was transmitted throughout the entire house, along with noise of air traveling through the ducts.
• "Crosstalk" was also a problem, where people talking in the front part of the house could be heard through the supply vents by people in the back part of the house.

After my modifications, all of the above problems disappeared, except for localized mechanical noise at the air handler. Being that it's in a hallway, it is not objectionable.

[WorryWart]

Is all of your ductwork of sheet metal construction now?

Flex duct must be sized properly and installed tightly. You would also not need to replace all of the metal ductwork, only the last six feet or so to each supply vent in each room. That's what I did at my FIL's house, for the most part, except the one section of trunk I replaced with a length of flex, as it was easier than doing each supply vent. It worked just fine.

Here was the full situation that made my FIL's house unbearable until the modifications were made:

• The construction of the air handler has the blower wheel and motor above the indoor coil.
• The plenum above the air handler going into the attic is insulated on the outside, not the inside. There is no insulation on the inside to attenuate noise. With this type of duct design (radial), exterior insulation on the plenum is normal and expected.
• All of the ducts feeding out from the centralized supply plenum were round metal duct, externally insulated. Nothing to dampen both blower and duct noise.
• Supply grills were stamped steel variety, which are restrictive and can create a "rushing" sound when too much air is forced through the vanes.
• The nature of the blower wheel described in my last post was transmitted throughout the entire house, along with noise of air traveling through the ducts.
• "Crosstalk" was also a problem, where people talking in the front part of the house could be heard through the supply vents by people in the back part of the house.

After my modifications, all of the above problems disappeared, except for localized mechanical noise at the air handler. Being that it's in a hallway, it is not objectionable.

Thanks for the ideas!

Frankly, I don't know if all our ducting is metal....they are all pretty insulated if memory serves me, and do metal ducts come in round? I certainly hope that replacing ductwork will not be necessary....although the discussion on this thread leads me to believe it is certainly a possibility. I just don't know why the problem didn't arise with the previous unit!

I'll keep your checklist handy, in case the other fixes aren't effective.

[captube]

never mind i'm going to bed.

[WorryWart]

shophound...

Yeah, I see what you also had round, externally insulated radial ducts....Sounds like what we have... :-(

[WorryWart]

Originally Posted by Mr Bill View Post
Look it's easy to find out if it's air flow related or freon pumping through the lines. Heres what you do go outside and "hopefully" you have a disconnect on your outside condenser well flip that sucker off, if no disconnect well kill the breaker to the outside unit and then go back in and turn on the unit inside to the fan on position on the thermostat and see if you still hear the noise.
a

Yup, I will do this in the morning. So if it's not the refrigerant line, then I'll know it can be fixed by either adjusting blower speed or fixing duct problems. Am I finally getting it--please say I am! :-)

[Shophound]

shophound...

Yeah, I see what you also had round, externally insulated radial ducts....Sounds like what we have... :-(

The previous homeowners at my FIL's place had replaced the original Lennox equipment prior to FIL purchasing the house. No idea what the original tonnage was, but I have a feeling the replacement equipment was upsized. I ran load calcs on that house as it sat before I made mods and the equipment on the ground was oversized according to the load calc. Oversized equipment often means it moves more air than the original equipment. With all metal ducts, that extra air motion will manifest as unbearable noise.

[WorryWart]

The previous homeowners at my FIL's place had replaced the original Lennox equipment prior to FIL purchasing the house. No idea what the original tonnage was, but I have a feeling the replacement equipment was upsized. I ran load calcs on that house as it sat before I made mods and the equipment on the ground was oversized according to the load calc. Oversized equipment often means it moves more air than the original equipment. With all metal ducts, that extra air motion will manifest as unbearable noise.

Yeah, sounds like our dilemma. We upsized to a 3.5 heat pump (from a 3 ton A.C) and the only addition in finished area was 790 sq ft in basement.

We have an airflow problem into my son's bedroom, and there is only one vent in the basement. I wonder if adding a duct in each place would alleviate the pressure on existing vents? (I have NO hvac knowledge/experience, so please don't flame me on this one!)

[WorryWart]

never mind i'm going to bed.

I really appreciate your input and help! Have a good weekend.

I'll post an update (hopefully a happy one) at some point.

[WorryWart]

Thanks to all of you for being supportive, helpful and interested during my trauma. I'll keep you updated!

[KarlwithaK]

atleast woorywart is doing homework and not just calling every hvac company in the city and complaining. sounds like an airflow issue. people underestimate the issue.

[Milk man]

You have to be kidding me! A three, hell no! It's a zero, put in by zeros, and supervised by a zero.

Cut you losses now and hire someone that knows what they are doing to repair that cluster. Be prepared to put out some coin.

Or try to contact someone from Goodman Manufacturing. Here's the real test boys. (Many know my opinion of Goodman). If they are such a great company, Goodman should pay to have this cluster done right. Then ban the sale of any Goodman equipment through their distributors to this installing company.

[Twilly]

I just may give you a call, Twilli! You sort of remind me of the William Shatner character on Boston Legal! :-)

Twilli Crane