A/C Problem - Need suggestions (Cool: how much, new house, closing)

[sam31]

Hello everyone,

We have 11 month old home built by VB. Since the day we moved in, we are experiencing in-balance of airflow throught out the house. During summer time, A/C runs with 3 degree difference between downstairs and upstairs units. When bedroom doors are closed, the temp. inside all the bedrooms shoot up by 5 degrees. Now in winter with heat on, master bedroom on 1 st floor gets warm by 5 degrees and master closet temp. rises by 8 degrees. Upstair bedrooms (no return installed) remain cold by 2 degrees.

It is soo bad that I need to wake up every night just to make sure I open the bedroom door for at least 10 minutes for hot air to get out. We are very unhappy about this.

When we asked VB to evaluate the air flows, they sent their own A/C company which acknowledged the temp difference but told us the A/C units are installed and working properly. In order for the airflow to work better, they have asked us to use the celing fans through out the house
and keep the upstair A/C unit in circulating mode (in winter only). They sent us a letter stating that no further action will be taken.

We invited 2 other A/C companies and they told us that there is air inbalance. We gave these reports to VB already.

We have one month left on our warrenty and I am wondering what actions can be taken in order to ask VB to correct the problem. Your suggestions will be appreciated.

One very unhappy VB customer.

[vms_cmiamt]

Speak to the president to voice your concern, and seek legal counsel to prepare to take VB to court if they will not take action to correct the defect in your home's air conditioning system; go over the warranty with your lawyer. Most likely you will have to sue VB, developers like these need a kick in the butt to get them to remember customer service is important.

[kreeyax]

I think what you are experiencing sounds pretty normal for a 2 story house. Why not try setting your upstairs thermostat at 3 or 4 degrees higher than downstairs? That's how I balance mine out. Closing those bedroom doors upstairs can cause a greater differential because your thermostat is probably out in an open area that can be heated/cooled from the combined downstairs heat/AC. I notice this especially in the morning when I wake up when my heat goes from 65 to 68, the downstairs unit runs a lot and it heats the air up on the second floor to 72 or so. Heater never comes on upstairs since it's so warm, so the bedrooms stay cold if the doors are closed.

As far as your master getting 5 degrees too warm at night, why not set your thermostat to go down by 4-5 degrees when you go to bed? I assume you have programmable thermostats?

[cBach]

This is a very common problem.

What I do is have the lower floor have a lower temperature at night than the upper floor during the winter. I also close the vents to the master bedroom and bathroom during the winter, and open them during the summer.

Also, the timing is essential, have the upstairs furnace kick in earlier in the morning so the upstairs bedrooms can warm up prior to the downstairs furnace kicking in to warm up for the morning.

Bottom line is upstairs furnace should ALWAYS be set at a higher temperature than the downstairs furnace, whether summer or winter. Usually 1-2 degrees I found is the sweet spot.

[kreeyax]

Originally Posted by cBach

Bottom line is upstairs furnace should ALWAYS be set at a higher temperature than the downstairs furnace, whether summer or winter. Usually 1-2 degrees I found is the sweet spot.

Agreed. If you have a very open 2nd story floor plan with the thermostat right out in the open, you'll probably need more than a 1-2 degree differential. For me it's about 3-4 degrees differential. You have to learn how to balance it properly yourself, otherwise you'll overwork one unit and underwork the other unit and end up with rooms that are too hot or cold.

[sam31]

Thank you very much guys for your suggestions.

We always keep 3 degree difference between downstairs (69) and upstairs(72) units. Like I said, during summer time, all the bedrooms in the house gets pretty warm when door is closed and in winter time, master bedroom (downstairs) gets warm and other bedrooms (upstairs) remain cold.

[ethanw]

1. You need a competent HVAC company to re-balance each and every room. Few degrees difference is normal. But you need to get proper flow and volume of AC or Heat into each room.

2. Ensure filters are changed timely, if not, they can negatively impact the performance

3. There few air returns in your house that allows the air to flow back into the HVAC system, typically those are where the filters are located. In my house the metal fins were actually almost closed. Get a screw driver and increase the gap in those metal filters.

4. Ensure the design of the air ducts is appropriate for the size of your house and rooms. What I’ve learned from both of my houses is that the builder did cut corners and didn’t have enough HVAC duct size or number of HVAC ducts in the house. We ended up adding more ducts and increasing the size on some of the existing ducts, which means more $$$ for the builder.

5. Lastly, if you lots of windows, large windows or your hot location is under sun a lot, west, you may consider tinted windows or sunscreen

By pushy, demand what it needs to be done, get educated. Get a competent third part HVAC company to provide you with a written report of issues and what needs to be done.

[davidtk]

Sam,

Is there a decent size gap between the bottom of your doors and your floor/carpet? If not, then there is no room for the air to exit that bedroom, unless that room has a dedicated air return. Ask an A/C person how much of a gap you need, but I would think at least 1 inch. This is a simple issue to address that can dramatically affect heating and cooling.

If you need more of a gap, remove the door and shave the bottom. You can hire someone, although I did it myself.

[davidtk]

We recently moved from a 10 year old 2 story house to a brand new 2 story house. It's much easier to keep the temperatures consistent from room to room AND upstairs to downstairs in the new house, which I attribute to 2 things:

1. Our old house had an 'open air' concept, with a 2 story living room and most of the upstairs opening to the downstairs. It basically made the entire house one large zone. Because of that and the fact that heat rises, the upstairs was always 2-3 degrees warmer than downstairs. If I wanted the upstairs cooled to 77 degrees in summer, then that meant the downstairs would be at 75 degrees.

In our new house, the only connection between upstairs and downstairs is the stairway. Now I can actually control the temperature independently between the 2 floors. I can make upstairs COOLER than downstairs, which I never could in our old house.

2. Return air ducts in every bedroom. Even with the bedroom doors shut, each bedroom has a consistent temperature because the return air duct helps to prevent air from being trapped.

Just my theories, but whatever it is the HVAC is much better in the new house.

[cBach]

Originally Posted by davidtk

Sam,

Is there a decent size gap between the bottom of your doors and your floor/carpet? If not, then there is no room for the air to exit that bedroom, unless that room has a dedicated air return. Ask an A/C person how much of a gap you need, but I would think at least 1 inch. This is a simple issue to address that can dramatically affect heating and cooling.

If you need more of a gap, remove the door and shave the bottom. You can hire someone, although I did it myself.

Another option is to get a door with a vent, they can look somewhat stylish. Then you can keep the door closed but air will circulate.