noshow_nogo

new homeowner, always rented so I'm just upping my home IQ, bear with me. It's a new construction,.. have 2 zone AC/heat. zone 1 is the LR, kitch, dining, and full finished basement. zone 2 is 2nd floor where all bedrooms are. There is an attic where one of the units seem to be placed and operating.

Each regular bedroom has one 6"x6" vent, and the outside hallway has a huge vent on the ceiling about 24"x24" which I'm learning is the cold air return. The master bedroom has 2 of the 6"x6" vents and a 11"x11" cold air return. The problem initially was the cold air return would make a howling noise and the air being sucked out was so strong. I remedied the noise by placing an air filter behind the grate, however, the airflow is still strong. I can stick a piece of foam board on the grate and it will stick. Each of the bedrooms with just a 6"x6" vent are warm when the heat is on, however, the master bedroom with its own return vent is cold. It's almost as if the cold air return is sucking in all the heat that is trying to be put out by the two smaller vents. Should I contact the builder or is there an easy fix? Does this sound like something is wrong?

pinky_ttc

Interesting really. This sounds like my house. I have the EXACT same setup as you described. I bought my home new a year ago.

My master is slightly colder than my other bedrooms. I've always wondered why? However, it's almost 3 times as big as some of the other rooms along with a walk-in closet and bathroom, both which would equal another bedroom.....not to mention builder quality windows are probably not as efficient.

My cold air return in the master is on opposite ends of the 2 6x6 vents too...


Are the vents producing warm air and it just seems like your bedroom is colder than the others or are the vents producing cold air?

litesout

Probably has to do with where the bedroom is in relation to the air handler. My house is a single story with a single 4 ton unit. The air hander is in the garage which is on the opposite end of the house. The ducts run the lenght of the house before they get there which allows the air some time to cool in the winter and warm in the summer before reaching the master suite. It was the same way in the old house. Bedrooms 2 and 3 (the non masters) were on the opposite sides of the house so they suffered the same effects. Unfortunately, due the extreme conditions here in Florida (heat in the summer more than anything) there isn't a lot you can do about it.

As far as the return is concerned, there really isn't anything you can do about that. You can ask the builder if they'll move it out of the master bedroom, but to promote good air flow, I wouldn't recommend it. If the house is properly sealed (and it sounds like it is) having it in there should be pulling air from the rest of the house (downstairs, hallway, etc) into the master bedroom to promote good flow. It is odd that you'd have 2 returns that close to each other though. I'm assuming the master is upstairs, correct?

noshow_nogo

the vents are producing warm air business as usual, but the room is just cold. the distance of the cold return from the one in the master and the one in the hallway is 10 feet

A bit different. I am 99% sure there is a secondary air handler in the attic to handle the 2nd floor bedrooms. I can hear machine whirring up there. The masters is upstairs with the other 3 non-master bedrooms, yes.

I'm really considering putting another air filter backwards in that cold return to reduce how much air moves out. There is a much larger cold air return in the hallway closeby. I'm already testing out thermal curtains to help with the temp regulation, but these anderson windows are bad ass in insulating.

NSXNEXT

iTrader: (2)

Seems like the return in the MBR is either sized too large or, based on the fact that the air handler is located in the attic, you have too many returns.

Typically there is one decent sized return in the upstairs hallway and one small return in each bedroom.

Do you have more than one air handler? Is there on in the basement?
Have you contacted the builder?

5o9

Don't plug up the return with filters.

Seems like the room needs more heat, so you need balancing. There should be dampers to each room in the attic ductwork, so you make sure the cold room is fully open, and you close the baffles a bit on the hot rooms.

I bet the builder never balanced the system, and might do it for free, a good job they measure airflow volume and temp

thunder04

iTrader: (1)

I have the same problem. My master bedroom has its own return and it's always cooler than the rest of the house. But, in my case, the master bedroom was remodeled and made a little bigger. So I don't think the previous owners had the HVAC system balanced and/or resized.

BUT, the weird thing is, during the summer with the A/C, it's one of the COOLEST rooms in the house. So I dunno what the deal is there.

noshow_nogo

NSXNEXT - I'm 99% sure there's a separate air handler in the attic directly above the MBR. The builder is a jackass and won't return my calls. He will reply to emails, but it's excuse after excuse. I'm thinking my first recourse would be contact my attorney who oversaw the transaction and see if they can makeup a more official notice to hurry the fck up. Does anyone think this type of rebalancing can be done via new home construction warranty?

5o9 - I've been a renter all my life, so I don't quite understand fully the mechanics of HVAC,... I'm trying to read up online and learn, but I simply don't wanna screw things up royally.

5o9

^ Send him an e-mail to send out his HVAC guy, noting his otherwise good reputation with you, and a one year warantee on new construction.

Stuffing the return with filters is about the worst thing you could do, makes the furnace blower work harder...

As a balancing test, close off the hot air vents in the warm rooms temporarily, and see if the cold room gets hotter. This is not the permanent solution, which lies in the baffles located in the attic, but should tell you if the balancing is going to work.

Best of luck, if I built the house, I would run right out and fix it.