[askmrjesus]

RACER X said:
ok, i see what your thinking, i was told on another M/C board by a custom home builder to drill only near the center of th joist. the upper and lower parts are weight bearing areas whereas the center has the least amount of weight.

That makes sense to me.

JC

 

[ducati_atx]

hows about calling the builder to fix that. Pretty crap construction if you ask me...

Should have caught that during your inspection. Wonder how it passed city with that setup. Yeesh.

 

[Flexin]

Just leave it alone, I'm sure that is not the only duct in the house. Your only gaining 3 inches by moving the joist.

Slow down. Z might like an extra 3".

James

 

[Mike Reyna]

askmrjesus said:
Oh, by the way, the correct tool for cutting that joist would be a Sawzall.

The Sawzall, however, is a dangerous power tool in the hands of a novice, so I don't recommend using one without first obtaining the proper training from the Power Tool Safety Foundation.

In the meantime, you could begin with a butter knife.

Remember: Start small! :nanana

JC

:lmao

 

[zer0netgain]

hows about calling the builder to fix that. Pretty crap construction if you ask me...

Should have caught that during your inspection. Wonder how it passed city with that setup. Yeesh.

+1

That's an HVAC guy who doesn't know his job. He should have put in two intake ducts....one on each side of the support beam if he couldn't find a better place to install the A/C return, and I'm not anything close to an HVAC expert.

As dirty as your filters look, I'd consider having someone who cleans and sterilizes HVAC systems take a look. I'd not expect a problem in a new house, but if that was an existing home, God knows whats in the ductwork.

A proper cleaning can cost $$$, but afterwards, if you use allergen-level filtration on the return, you shouldn't need to repeat it for several years, and it makes a difference if you suffer from allergies.

 

[RCM78]

First of all, That filter doesnt look dirty at all. Dont waste your money on cleaning ducts that dont need it...

Now, Having a filter grill is very common and usually makes it easier for the home owner to replace the filter without going into the furnace.

What should have been done with that is the beam running through the filter needs to be cut and the filter grill framed out. This way air flow isnt hurt and structural integrity is maintianed.

Oh yeah, I'm an HVAC tech...

 

[Sauron]

I can't believe that meets code. You just bought this house new.

Have them fix it.

 

[101Lifts2]

That's the intake duct that supplies air to the furnace. It's actually fairly common for the filter to be there.

Leaving the joist in the way restricts the airflow, and lessens the effectiveness of the filter.

This is why GM should not build houses.

JC

LOL...the joist only restricts the airflow if the airflow is already at near max capacity through the 2 foot duct, which it is not. If he moved the joist, it wouldn't make any difference. That and on top of the fact that furance filters are the farthest thing from a "good" filter.

Also, I've worked construction for 15 years and never seen the filter not near the furnace. Must be a southern thing.

 

[101Lifts2]

yeah, new house, look at the filter only 1/2 of it is dirty, therefore the A/C unit is working 2x as hard to get the same amount of air. instead of a 20x30 filter it;s theoretically a 10x30.

You weren't an engineer were you?:redflip

If you have (just for numbers sake) 50CFM flowing through the filter at 90kpa absolute and you restrict half of it, your going to have around the same pressure and CFM because furnace ducts are not restrictive. The amount of available air is still there, it just has to go to the part where the joist is not.

Will the furance require more power to turn the blower motor? Won't even be measurable and the amount of the airflow will not change.

 

[RACER X]

so then why is 1/2 the filter dirty and the other not?

 

[101Lifts2]

so then why is 1/2 the filter dirty and the other not?

:laughing Because that end is covered by the joist which so happens to be about half of the opening...the filter fits correctly in the opening and viola!

Listen... to make this simple...if you cover up a portion of the duct, the air velocity over the other part has to increase to keep the pressure inside the duct as best at atmospheric as possible. Therefore faster air with less space to go through will yeild the same volume of air. Get it?

Now this is granted the duct and filter are not restrictive to begin with, but your only covering up 3inches of duct.

 

[JumpmasterRT]

101Lifts2 said:
You weren't an engineer were you?:redflip

If you have (just for numbers sake) 50CFM flowing through the filter at 90kpa absolute and you restrict half of it, your going to have around the same pressure and CFM because furnace ducts are not restrictive. The amount of available air is still there, it just has to go to the part where the joist is not.

Will the furance require more power to turn the blower motor? Won't even be measurable and the amount of the airflow will not change.

I'm not an engineer but I am a Respiratory Therapist and well versed in gas physics.

You're correct about the pressure being the same at the duct and that the furnace won't be affected because the same volume of air will reach the duct opening at a faster speed.
However, that's the problem. With increased flow through the filter, the pressure placed on the filter media increases thus making it less effective and that's the important issue.
Unless the filters he's purchasing are rated for a higher pressure than the standard blower unit produces.

Ed, you need to have an HVAC guy come out and do an air velocity/balance test on it. It may be no issue but at least you'll know if you need to do anything at all.

Hell, you may end up just having to spin the current filter 180* and use the clean side :laughing

 

[RCM78]

101Lifts2 said:
That and on top of the fact that furance filters are the farthest thing from a "good" filter.

Also, I've worked construction for 15 years and never seen the filter not near the furnace. Must be a southern thing.

Fiberglass filters are good enough. The only reason there in there is too protect the equipment from getting clogged with dirt. NOT to filter the air. All the new 3M pleated filters or electrostatic filters restrict airflow as much as 40% and actually cause problems for both the furnace and A/C.

If a customer has a medical need for air filtration then I allways recomend an "Electronic air cleaner". They work great and do not restrict airflow.

Now, the filter grill has been used alot longer then I've been in the business and thats just about 20 years. Usually they are used if the unit is in the attic and the installer uses one central return located in the ceiling. They can be used for any application but usually when you see one it's a good bet thats the only return in the house. Having one central return may not be optimal but will work just fine on a single floor home.

 

[ducati_atx]

101Lifts2 said:
Also, I've worked construction for 15 years and never seen the filter not near the furnace. Must be a southern thing.

Its very common here in texas not to have the filters (return filters) at the furnace. All three of mine are at minimum 10'+ away from them. One is probably 30'.

As for the filter - it really isnt dirty - however, it might be good to opt for the non 99 cent filter.

Im still surprised that the inspection didnt catch this. Did you have the house inspected when you purchased it?

 

[101Lifts2]

.....However, that's the problem. With increased flow through the filter, the pressure placed on the filter media increases thus making it less effective and that's the important issue.
Unless the filters he's purchasing are rated for a higher pressure than the standard blower unit produces......

OK...furnace filters catch stuff like feathers, hair, yarn:redflip they will pass sand and dust easily so I'm thinking the effectiveness of catching the big shit isn't gonna change.

 

[101Lifts2]

Its very common here in texas not to have the filters (return filters) at the furnace. All three of mine are at minimum 10'+ away from them. One is probably 30'.

As for the filter - it really isnt dirty - however, it might be good to opt for the non 99 cent filter.

Im still surprised that the inspection didnt catch this. Did you have the house inspected when you purchased it?

Why would an inspector check this? I mean inspectors are suppose to find shit wrong with the house saying the house was built correctly and to code.

Apparently the cheap houses in TX have their flaws. :laughing

And of course he didn't pay for an inspector...Asians are cheap:redflip

 

[trikzee]

Don't put a hole in anything until you check with your home warranty. I would do everything in my power to have the builder come in & do it right.

 

[RACER X]

yes and inspection was done, no he didn't catch this.

as for airflow, if there's enough suction to close the door thats right underneath the return, my fear is that the a/c is having to work hard having to "suck" thru half the filter, it was designed for a 20x30 filter, but is down to a 10x30

it's a 2 story house w/ 2 a/c's and 2 returns. upstairs one is fine.

 

[MasterDrazhar]

I'd have the builder come back and frame out that opening correctly.

They'll do it like JC suggested, by cutting the floor joist back on either side and boxing in the opening connecting the 3 adjoining joists parallel to each other... and then boxing in the actual opening if needed.

 

[goof2]

RACER X said:
yes and inspection was done, no he didn't catch this.

as for airflow, if there's enough suction to close the door thats right underneath the return, my fear is that the a/c is having to work hard having to "suck" thru half the filter, it was designed for a 20x30 filter, but is down to a 10x30

it's a 2 story house w/ 2 a/c's and 2 returns. upstairs one is fine.

+1 on having this fixed by your builder under the warranty they provide. In an existing house fix it yourself, but why bother if you don't have to.