Return duct "boot or no boot"

ads67 · 01-08-2009, 11:08 PM

i recently had an high efficiency furnance installed in my house. when the sales rep/contractor 1st visited my house they suggested that i also change the rerurn duct and boot (seeing that the orignal was starting to rust and the return duct was not an appropriate size ...too small for the new furnance). i agreed with their recommendation and asked that they price the replacing of return duct/boot into the installation cost. at the time of the installation i was informed by the contractor that it would not be possible to install the boot because the return duct (with the boot) would not align with the overhead duct. so not to incur more cost (to make it happen) i allowed the return duct to be installed without the boot. my question to dyi members is, "is the boot an essential component?" i beleive it is. what i have now for the return duct is a rectangular box connecting to the overhead duct and furnance.

ps i'm a new dyi member as of 01/08/2009

thanks in advance,

ads

**beenthere** · 01-09-2009, 05:40 AM

Post a pic of the set up.
Along with dimesions.

Garasaki · 01-09-2009, 09:56 AM

What size boot is it? I wear a size 10 or 11. I might be interested in buying it off you.

No wait, I'm not going to wear a rusty boot around. Nevermind.

Post us a pic. The term boot as you are using it isn't clicking for me.

JohnH1 · 01-09-2009, 12:27 PM

I think you are talking about the elbow at the bottom of the return drop were it connects to the furnace. They do help lower the static but they can also have a nice filter slide for easer filter changing. Depending on the complete duct design static they are not always needed.

AndrewF · 01-09-2009, 01:33 PM

arent some boots rubber to minimize the vibration between the AH and the ductwork?

JohnH1 · 01-09-2009, 01:58 PM

Not the boot itself. You would add a flexable duct connector.

hvaclover · 01-09-2009, 02:03 PM

Quote:

Originally Posted by AndrewF

arent some boots rubber to minimize the vibration between the AH and the ductwork?

No. What you are thinking of is a flex connector the same dimensions as the return air drop. It is used to eliminate vibrations and make the installation easier.

Garasaki · 01-09-2009, 02:30 PM

See this is exactly what I mean.

Is the OP saying "boot" and meaning "flexible connector" or is he saying "boot" and meaning "sheetmetal return plenum"....

hvaclover · 01-09-2009, 02:45 PM

The image in left side of pic is a cold air boot

ads67 · 01-09-2009, 05:44 PM

If you google air duct return boot you'll find many pics (click the image button). Terminology used in my post was what was quoted to me by HVAC professional. So, if it was an incorrect term (which i don't believe it to be) pls. don't shoot the messenger. Looks like Hvaclover did his home work.

I will post a pic of the furnace this weekend. I do appreciate everyone's willingness to offer an opinion on my post Q ...yeah ...i wear a size 12 1/2 boot; Garasaki let me know if you are still interested in making the purchase?

Garasaki · 01-09-2009, 06:08 PM

Quote:

Originally Posted by ads67

Terminology used in my post was what was quoted to me by HVAC professional. So, if it was an incorrect term (which i don't believe it to be) pls. don't shoot the messenger.

I did understand when I asked about it that you were merely repeating what an installer told you. Exactly why a picture is so useful in this instance - it allows everyone to know exactly what you are talking about.

And, FYI, hvaclover posted a picture of a sheetmetal plenum and a canvas flex connector so I'm still a little bit unclear what your original question is...

You descibed a sheetmetal plenum connecting your new high eff furnace to the existing return duct. Your question APPEARS to be, is the "boot" necessary, and you APPEAR to be using the term "boot" to describe a canvas flex duct between the sheetmetal plenum and the furnace.

I would suggest the answer to your question is "no, the boot is not required" however one of the reasons it is there is to reduce vibrational noise from the furnace to the return duct. If you are not currently annoyed by any noise from your furnace right now, then you should be fine without the canvas flex duct. You do have a filter on that furnace, right?

ads67 · 01-09-2009, 11:16 PM

i believe i've received my answer. attached are pics of boot (that wasn't installed) and return air duct (furnace1/2.jpg).

thnx again for taking the time to offer your opinion on this matter.

ads

JohnH1 · 01-09-2009, 11:31 PM

The boot would allow for better or more even flow across you filtration unit but would move the return drop further from the furnace. A couple of 45 deg fittings or a offset would bring the drop back to the upper conection. Long story short it would be nice to have but you will work ok without it.
My 2 cents

ads67 · 01-10-2009, 12:05 AM

Quote:

Originally Posted by JohnH1

The boot would allow for better or more even flow across you filtration unit but would move the return drop further from the furnace. A couple of 45 deg fittings or a offset would bring the drop back to the upper conection. Long story short it would be nice to have but you will work ok without it.
My 2 cents

your 2 cent was most appreciated. i really wish the boot was installed but will learn to live without it. one last q ...the installer placed the filter in with the air flow arrow going against the air flow. the error was pointed out to me by an air duct cleaner who came to inspect the ducts and provide quote to have them cleaned. while removing the filter he realized that air filter was inserted incorrectly and pointed it out to me. due to the duct needing to be cleaned the filter was quite dirty for only being in for less than a month.

seeing that the furnace installer was coming out the same day to attend to an issue with the tankless water heater, i made him aware of this error when he arrived. he then told me that it didn't matter which way the filter went in ...is this true? i told him that i did not agree with his response, so he then told me to just turn it around. i said no ...the filter is dirty. he then proceeded to take the filter outside to knock off the filter. he returned with still dirty filter (minus the clumps of dirt). i told him that i was not comfortable with the filter being flipped and that he return it back to how it was and a new filter be provided (seeing that the furnace was recently installed and the error was his). back to my question ...does it matter what direction (with or against air flow) the filter is inserted?

ads

Daltex · 01-10-2009, 02:48 AM

It looks like a 5" media filter? If so it shouldn't matter as the main purpose of the arrow is to allow the filters integrated support to keep the media from collapsing into the blower opening up an air bypass. A 5" filter would not be as easily bent as a 1" filter.

Since it's dirty enough to shake off clumps of dirt already, I'd make sure the rest of the trash is out of the return ducting and then just buy a new one. Why didn't the installing company clean the trash out first?