New Home HVAC Question

[Roboman]

I am looking at buying a new home from a local builder with a good reputation.

Once concern I have is the HVAC system.

It is a dual zone system with a gas furnace and AC system for the 1st floor and basement and a heat pump in the attic for the second floor. This is in Maryland outside Washington DC so summers are hot and humid for all of July and August.

My concern is putting a heat pump in the attic: how effective can it be if it's working in an attic that will probably reach 150F in the summer?

The other concern is if it breaks or needs service who can go up in a hot attic and actually repair it during the summer?

I hear that this arrangement is common so maybe this has been all figured out but I'm a little skeptical.

Also, they are using Goodman so I'm think of asking them to change to something I have more confidence in like Carrier/Bryant. Based on the great feedback I received on this form I put a new Bryant system in three years ago and have been very happy with it.

Thanks,
- Robert

[big sky hvac]

I think you'll like having two seperate systems vs. just one when it comes to cooling the upstairs. The heat of the attic will reduce the efficiency a little bit, but it won't really be noticeable to you. The ductwork in the attic should all insulated. If you were to only have one system, the upstairs may be a little warm, unless the single system was zoned. As far as going up there(attic) to work on it, it's not pleasant but it is part of our job. If you have yearly maintenance performed on both systems, it'll help reduce the chances of having any breakdowns. It won't eliminate the chance of having a breakdown, but the majority of my regular customers that have yearly maint. done have fewer problems than those people that wait until the system breaksdown without any maint. at all.

[doc havoc]

X2 what big sky says, along with this...If the equipment is installed properly, it shouldn't matter who the manufacturer is. I think you'll find as good or better warranty on the Goodman equipment as you will with most other equipment. And yeah, as awful as it sounds, going into that attic in the summer is one of the things we are paid for.

[bigkutta]

I live in the MD burbs too, and this setup is very common (as is in my house) around here, so I dont think a tech will have a problem working up there. As the previous poster said, the most improtant thing is that you ensure during your home inspection that the ducts are well sealed at the connections/joints and that the ducts are then insulated.

My home is older and some of the connections had come apart letting all the air escape out of the ducts and also sucking in hot air from the attic. You want to avoid this and make sure you let the builder know that this is a top priority for you. Also make sure they air seal the attic completely. These 2 will be the biggest bang for your buck

[cuchulain]

I wish all it reached is 105 in the attics during the summer. Down here it's not uncommon for them to be 140 and yes we do go up in them to work. We TRY not to, but it does happen.

[lentz]

When that attic gets hot we put a wet towel around neck and set up a fan and can do what every needs to be done with out to much trouble. Have a large bottle of water near by. Those high temperture do get pretty rough.

[big sky hvac]

When that attic gets hot we put a wet towel around neck and set up a fan and can do what every needs to be done with out to much trouble. Have a large bottle of water near by. Those high temperture do get pretty rough.

My rule for attics is this: when the sweat stops dripping off the bill of my cap and starts "running" of the bill of my cap, it's time to get out, cool off and drink a lot of water.

[Roboman]

Thanks for the great responses. I feel much better about this now.

Anything to look for or ask concerning minimizing noise and vibration from the heat pump in the attic?

Bigkutta,
I think you mean seal the attic from the 2nd floor, correct?
The house I saw under construction looked like they do a good job sealing holes between floors and calking between 2x4's and spraying foam insulation behind electrical boxes.

I need to check and make sure they are using ridge and soffit vents. They had an option for an attic fan but I'd rather use a passive ventilation system for the attic.

Thanks
- Robert

[bigkutta]

Make sure the unit is placed over a hallway if possible (not over a bedroom), that should minimize noise. I can never hear mine.

Yes, I meant air sealing the attic from the 2nd floor, which includes exactly the things you mentioned. If possible, do a walk through to check the air sealing before the insulation is laid down in the attic