Hi everyone! I'm in the process of replacing an existing central A/C unit and I have had a few quotes and I'm looking for feedback.
House: I'm in central MA. House is a colonial that was built in 1987 with what I'd say is average build quality. Walls are 2x4 with fiberglass, we added 18" of blown-in cellulose in the attic a few years ago. Windows are about 10 years old and draft-free. Doors are original and relatively draft-free - I've added some additional weather stripping. The first two floors are serviced by a central A/C that was retrofitted in 1994 and they are 3006sqft. There is an area on the first floor with cathedral ceilings and three very large SW-facing skylights. There is 1000sqft of finished basement with no A/C service and it remains cool all summer but the door is often open. The majority of windows are on the front and back of the house and the house faces east, gets early morning sun, remains in the sun all day and the sun sets coming in through the windows in the back.
Current HVAC: Current heat is oil-burning boiler with baseboards with 5-zones - fairly new and does a good job. The A/C was installed in 1994 with the air handler in attic and the system is a 4-ton Rheem. Install is a lot of flex duct but seems relatively well-done and not too leaky with straight and well-thought-out runs to the second floor - not so much the first floor. There is a large return in the hallway, a smaller return in the master. All 4 bedrooms, both bathrooms, and a large walk-in closet have supply ducts. There are only three supply ducts running through second-floor closets to the first floor - one in the living room, one in the TV area and one in the kitchen - if you think of a colonial three sections (left of entrance, entrance, and right of entrance) all three areas receive a centrally located supply duct. We've had the current A/C services every year and so coils are clean, etc.
The system does the job. We usually set the thermostat at 68F and it can maintain this temp on the second floor until it's 90F outside. At that point by 93F outside, inside is at 70F and by 95F outside, it's at 73-74F inside. Believe it or not the first floor is usually only 1-2F warmer with just the three supply ducts and always comfortable. There is a 25,000 BTU Window style A/C built into the wall in the rearmost room with cathedral ceilings and the three W facing skylights. We only need this unit when it gets above 90F and only during the late afternoon and it cools the entire 1st floor well. From a comfort POV the current system works but it si 27 years old so looking to replace it.
First Contractor - Spent all of 15 mins at the house. He looked at the current 4-ton unit, asked if we were comfortable with the unit and recommended no changes other than new air handler, condenser and line set. His recommendation was:
Bryant® Preferred™ - 4 Ton 16 SEER Residential Air Conditioner Condensing Unit Model # 126BNA048000
Bryant® 4 Ton Residential Fan Coil High Efficiency Multipoise Air Handler Model # FX4DNF049L00
Second contractor - referred by a friend who is in construction and works with this company frequently - spent maybe 20 mins looking around and his recommendation was also 4-ton but also said I may want to go 3.5-ton (isn't it his job to tell which one?):
Bryant A/C Condensor: Legacy 116BNA048000
Bryant Air Handler: FX4DNF049LOO
This quote also came in at 2/3 the first quote and so I asked if it made sense to bump up to a variable speed AH and 2-stage condenser. He replied if wanted to do that then he recommends a Bosch heatpump because right now there is a rebate for $1000 per ton and because the units only come 1-2 and 3-5 ton I would qualify for a rebate based on the 5-ton making this system basically the same cost as what he quoted me - this was late Friday and so I'm still waiting on the quote.
Clearly, there are things that can be improved with the supply ducts, etc - this is not my dream home and I have no desire to right all the wrongs of this house - I just want to be comfortable in summer for the next 10-15 years while my kids are in school and then my wife and I are out of here.
Questions:
1. It seems like no one does a Manual J and I know without one it's impossible to know but does 4-ton based on my house description sound reasonable?
2. If I stayed with Bryant does it make more sense, I know there will be an increased cost to go variable speed AH and 2-stage condenser?
3. I know very little about Bosch - he said based on the discussion based on the need for 3.5 or 4 ton that because everything on Bosch is variable speed that would remedy the issue? It can act like both? Is Bosch a good brand?
4. I have a few more quotes coming up - keep looking?
Any guidance appreciated.
House: I'm in central MA. House is a colonial that was built in 1987 with what I'd say is average build quality. Walls are 2x4 with fiberglass, we added 18" of blown-in cellulose in the attic a few years ago. Windows are about 10 years old and draft-free. Doors are original and relatively draft-free - I've added some additional weather stripping. The first two floors are serviced by a central A/C that was retrofitted in 1994 and they are 3006sqft. There is an area on the first floor with cathedral ceilings and three very large SW-facing skylights. There is 1000sqft of finished basement with no A/C service and it remains cool all summer but the door is often open. The majority of windows are on the front and back of the house and the house faces east, gets early morning sun, remains in the sun all day and the sun sets coming in through the windows in the back.
Current HVAC: Current heat is oil-burning boiler with baseboards with 5-zones - fairly new and does a good job. The A/C was installed in 1994 with the air handler in attic and the system is a 4-ton Rheem. Install is a lot of flex duct but seems relatively well-done and not too leaky with straight and well-thought-out runs to the second floor - not so much the first floor. There is a large return in the hallway, a smaller return in the master. All 4 bedrooms, both bathrooms, and a large walk-in closet have supply ducts. There are only three supply ducts running through second-floor closets to the first floor - one in the living room, one in the TV area and one in the kitchen - if you think of a colonial three sections (left of entrance, entrance, and right of entrance) all three areas receive a centrally located supply duct. We've had the current A/C services every year and so coils are clean, etc.
The system does the job. We usually set the thermostat at 68F and it can maintain this temp on the second floor until it's 90F outside. At that point by 93F outside, inside is at 70F and by 95F outside, it's at 73-74F inside. Believe it or not the first floor is usually only 1-2F warmer with just the three supply ducts and always comfortable. There is a 25,000 BTU Window style A/C built into the wall in the rearmost room with cathedral ceilings and the three W facing skylights. We only need this unit when it gets above 90F and only during the late afternoon and it cools the entire 1st floor well. From a comfort POV the current system works but it si 27 years old so looking to replace it.
First Contractor - Spent all of 15 mins at the house. He looked at the current 4-ton unit, asked if we were comfortable with the unit and recommended no changes other than new air handler, condenser and line set. His recommendation was:
Bryant® Preferred™ - 4 Ton 16 SEER Residential Air Conditioner Condensing Unit Model # 126BNA048000
Bryant® 4 Ton Residential Fan Coil High Efficiency Multipoise Air Handler Model # FX4DNF049L00
Second contractor - referred by a friend who is in construction and works with this company frequently - spent maybe 20 mins looking around and his recommendation was also 4-ton but also said I may want to go 3.5-ton (isn't it his job to tell which one?):
Bryant A/C Condensor: Legacy 116BNA048000
Bryant Air Handler: FX4DNF049LOO
This quote also came in at 2/3 the first quote and so I asked if it made sense to bump up to a variable speed AH and 2-stage condenser. He replied if wanted to do that then he recommends a Bosch heatpump because right now there is a rebate for $1000 per ton and because the units only come 1-2 and 3-5 ton I would qualify for a rebate based on the 5-ton making this system basically the same cost as what he quoted me - this was late Friday and so I'm still waiting on the quote.
Clearly, there are things that can be improved with the supply ducts, etc - this is not my dream home and I have no desire to right all the wrongs of this house - I just want to be comfortable in summer for the next 10-15 years while my kids are in school and then my wife and I are out of here.
Questions:
1. It seems like no one does a Manual J and I know without one it's impossible to know but does 4-ton based on my house description sound reasonable?
2. If I stayed with Bryant does it make more sense, I know there will be an increased cost to go variable speed AH and 2-stage condenser?
3. I know very little about Bosch - he said based on the discussion based on the need for 3.5 or 4 ton that because everything on Bosch is variable speed that would remedy the issue? It can act like both? Is Bosch a good brand?
4. I have a few more quotes coming up - keep looking?
Any guidance appreciated.
source https://hvac-talk.com/vbb/threads/2228291-Decisions-on-new-central-A-C?goto=newpost
No comments:
Post a Comment