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Mini-Split Advice

6 years ago
last modified: 6 years ago

We have a 1966 mid-century modern home (approx. 1800 square feet) that is on-slab without attics. There is currently a 25 year old ducted air conditioner on the roof and the original in-slab radiant heating still works. We're having the membrane roof replaced this summer and it's time for the freon-based A/C to go. We're looking into mini-splits that would handle our air conditioning needs and act as a back up for the 54 year old heating. So far, we've gotten two quotes, both using a combination of ducted air handlers and wall-mounted heads - one for a Daikin system, and one for Carrier. Because of the design of the house, there would be two multi-zone heat pumps on the exterior. There's a $10K difference in pricing! Functionally, it seems the two systems are very similar, so we're really confused by this pricing. The only big "limits" we've imposed is that the refrigerant and electrical lines can't be run all over the exterior of the house but, since one heat pump would be just outside the garage and the other is just outside a closet, that shouldn't be that big a deal. So, I guess my question would be: Is there a big quality/efficiency difference between the two systems that we're just not seeing? And should we be talking to a third HVAC contractor?

Comments (4)

  • PRO
    6 years ago

    I suspect your current system may be a package unit on the roof?

    The $10K difference in pricing is subjective, and you don't provide enough information to understand why this might have occurred.

    I can tell you the structure is quite large for mini splits, because mini splits are more or less spot cooling / heating appliances they require more equipment.

    More equipment leads to more maintenance, more cost repairing and ultimately replacing. Plus you have the head of the unit taking up space on a wall. A lot of people don't like the look of that, which will be important when you decide to sell this place.

    Due to how your current system is configured and if your goal is to get it off the roof that means things have to be moved, that costs money. But you don't describe any of this in your post. I can only guess here.

    The other thing you failed to address is climate. Where is the house located?

    Donna Collins thanked Austin Air Companie
  • 6 years ago

    Thank you for your answer. We are in Portland, Oregon in a Rummer house, which is very similar to the Eichler homes in California, with open plan post and beam construction and 2x6 tongue and groove car decking that is both the interior ceiling and the decking for the roof membrane. The roof is low slope over the kitchen and living room and flat over the bedrooms and baths. Our current system is from a company that is no longer in business in this area; they were absorbed by International Comfort Products. I do not know the tonnage of the unit, but it is A/C only and provides cooling to the living room and kitchen areas via two roof ducts. This system doesn't cool the bedrooms at all. It's also a freon-based system and can no longer be legally serviced or recharged.


    Mini-splits are pretty much the standard solution to heating and cooling in Rummer homes because of the difficulties in managing ducting. I realize they aren't ideally suited to being used as whole house systems, but the alternative is to run ducting over the roof, which is both unsightly on a very low-profile home and also tends to create issues with maintaining the membrane roof. Both HVAC contractors we've spoken to are offering essentially the same thing - a 3 zone, 3 ton heat pump on the north side of the house that will serve the master bedroom, kitchen and living room with a ducted fan coil unit located in the garage, and a multi-zone (3 or 4, depending on the manufacturer) two ton heat pump on the south side of the house feeding a wall-mounted unit in the guest bedroom and a ducted fan coil unit handling a third bedroom/office, a utility room, and a hallway that's open to the main living areas.

  • 6 years ago

    GET DAIKIN MINI SPLIT SYSTEMS

    https:/www.newcentralairconditioner.com/



    Daikin stays at the forefront of ultra-efficient inverter technology as well as creating safer refrigerants to keep up with the global demand to reduce CO2 emissions. They are the inventor of the variable refrigerant volume system (VRV) and an innovator in the split system air conditioning market.Daikin has also co-developed R-410A refrigerant with Carrier. They are the only manufacturer to produce their own refrigerant and compressors.


    Daikin is committed to meeting the challenges of global warming and a need for sustainable resource use by bringing you more efficient technology with minimal environmental impact. For more than 80 years Daikin has been producing innovative and energy efficient climate control products tailored to fit your needs. They have become a total solutions provider though unique product lines to fit your requirements and budget.


    Donna Collins thanked MiniSplit Heat
  • PRO
    6 years ago
    last modified: 6 years ago

    I do not know the tonnage of the unit, but it is A/C only and provides cooling to the living room and kitchen areas via two roof ducts. This system doesn't cool the bedrooms at all. It's also a freon-based system and can no longer be legally serviced or recharged.

    Ok first off, R22 Freon units can be legally serviced and recharged. Someone is trying to sell you on misinformation. Obviously a 25 year old unit is going to be difficult to get parts for if not impossible, especially a Freon based unit. You'll pay a higher price for the refrigerant but it's still readily available. I just bought a jug of R22 yesterday for a leaking coil replacement job I am doing later today.


    Residential units that contain less than 50 lbs of refrigerant are not under any mandatory replacement schedule. An 1800 sq. ft. structure in your climate is not going to contain anywhere close to 50 lbs of refrigerant.

    ICP is more or less Carrier, with a different sticker on the side of the unit. These companies are both owned by United Technologies Corp, a large multi-national conglomerate. I only say this to give you some understanding.


    I've seen similar homes like the Rummer model here in Houston area. That structure the design of it has a good number of challenges to make air conditioning work properly.

    The difference in cost between these two HVAC contractors that quoted the job could be due to experience in problems encountered. Your climate in Oregon is not overly extreme, but very humid.

    What that might mean? The HVAC contractor that quoted you $10K higher, may better know the challenges involved with your structure. OR maybe they don't have the experience with that particular structure and they are hesitant / want to be sure they don't risk their company's good reputation on a possible job gone bad.

    Good reputations can be ruined on one job gone wrong.

    The company offering this for $10K less may be inexperienced or they may be experienced to know what they can do the work for because they have done these structures in the past.

    So what does your gut tell you? You could get two more companies involved and see where they wind up quoting you.

    I can tell you this: When I quote a job, I quote it for what I feel the job is worth. I don't quote a job out of fear I am quoting it higher than some other company. I am a Licensed pro with a salty long history. If you call me - you get me and my ways.

    There is no magical science behind why there is such a disparity in price. It may be related to skill of the technicians on staff. This is an easy way to drop price is to hire a bunch of kids with no experience.

    But that isn't to say the $10K higher priced quote is any different in that regard. But you don't keep skilled technicians without paying them and you don't pay them without collecting for it down stream.

    With that said, if both these companies lied to you about being able to service an older R22 Freon unit, I think I would steer clear of that. If they are going to lie about that, what else will they lie about?


    R22 Freon Requirements CIRCA 2019 EPA 50 pounds or more rule.


    With that said, you should fix any refrigerant leaks, even though the rule as stated doesn't require you to do so.

    I service the Katy, Texas area.

    Donna Collins thanked Austin Air Companie