Air conditioning need/position in airtight house
Hi!
I am wondering if a standard mini-split air conditioner placed centrally can do the job to keep bedrooms cool in summer if i have a very tight home.
I’m trying to lower my heating/cooling installation cost and transfer that money to a better performance envelope. (Climate zone 6, R36 double stud walls, triple pane windows, r60 roof). So i am looking to replace a central forced air system by baseboards and a central location mini-split AC/heat pump.
I don’t want to reduce the comfort level of the home however and i’m scared of the associated “cheap” impression of baseboard heaters, even if they’re pretty ones… Any insight is appreciated!!
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Replies
I think your goal is admirable. But as to it’s success as in most things “it depends”. What you are planning can definitely work but it works best on smaller well insulated and sealed homes with a fairly open floor plan. It also depends on keeping the bedroom doors open for most of the non sleeping hours. If it’s as near passive house as your description indicates the bedrooms shouldn’t lose too much heat even if they are closed for sleeping.
I would rethink placing the unit centrally. Mini splits disburse air similar to the way dynamic speakers project sound. They are not dipole units like electrostatic speakers are. Probably the best situation is to have the unit placed on an exterior wall in the living room area where you probably spend the most time. Ideally I would think the best case for a single unit would if all the bedrooms, probably not more than two, we’re both in the direction that the air is being blown. In other words, for a single mini split to be most effective the rooms farthest away must be in the direction the mini split blows the air.
I see that this thread is already a year old, but I'd still love to offer some advice. If you're still looking for a cost-effective way to cool your bedrooms in the summer while maintaining the comfort level of your tight home, a standard mini-split AC placed centrally can be a great option.
Why do you want to replace the existing central HVAC system? If you're looking to reduce your installation cost, leaving the existing system in place is certainly the cheapest option! If you are thinking about energy saving, heat pumps don't really save money over conventional air conditioners during the cooling season, because air conditioners are themselves basically heat pumps. For a comparison of heat pump to conventional A/C system, you'd need to compare things like SEER ratings. It's during the heating season when heat pumps have an advantage in terms of operating costs.
Bill
I see that this thread is already a year old, but I'd still love to offer some advice. If you're still looking for a cost-effective way to cool your bedrooms in the summer while maintaining the comfort level of your tight home, a standard mini-split AC placed centrally can be a great option. It's a smart move to focus on improving your home's performance envelope with energy-efficient upgrades like R36 double stud walls, triple pane windows, and an R60 roof.
Also, check out this ac service https://hot2coldairconditioning.com/ if you need any help. Consider that by switching to baseboard heaters and a central mini-split AC/heat pump, you can save on installation costs and enjoy efficient cooling.