New mini split whole house question
We have just completed a whole house minisplit system in an 1850 2 story farmhouse of 4200 sq ft. The house has good ceiling and wall insulation modern new windows and a mostly stone uninsulated full basement. We are located in Upstate NY and replacing a single zone ducted natural gas furnace with a 10 zone air heat pump system. We had the heat load calculated professionally and have 30% over the calculated heat load requirement for the space.
I am unclear as to an appropriate temperature settings or set ups for the individual heads to make my wife happy on the couch? Also what impact will the unheated basement have on the system. We have sealed the old heating grates. Any suggestions are ideas would be most welcome.
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>We had the heat load calculated professionally and have 30% over the calculated heat load requirement for the space.
>> Usually, oversizing is not always the best approach. It can lead to short cycling and result in reduced comfort. This is important to understand because most of the time the systems are designed to meet the "coldest" and the "warmest" days.
>I am unclear as to an appropriate temperature settings or set ups for the individual heads to make my wife happy on the couch?
>>Can you clarify your questions? I get the sense that there is quite a bit of information that is being left unsaid. The temperature would be set at whatever is comfortable based on the personal preferences of the person. Some prefer it to be cooler, some prefer it to be crazy hot. In essences, I would expect your wife to be in the best position to answer your question.
>Also what impact will the unheated basement have on the system. We have sealed the old heating grates. Any suggestions are ideas would be most welcome.
>> This might be where the oversizing of the system will serve you well. Knowing that "hot air - rises" and "heat-moves towards the cold", I would expect that the basement would "steel" heat from the the heated areas. Generally, cold air will "fall" so the cold air should not move to the upstairs unless there is higher air pressure in the basement.
This said, there is something called stack effect where the hot air rises and often escapes through the roof assembly. When the air escapes through the roof assembly, it leaves a vacuum (an empty space) to fill. Usually that empty space gets filled by colder air that is pulled from the wall assemblies/windows. While the colder air may not be exclusively pulled from the colder basement, we can still expect that the basement walls/floor/windows would provide some of the air to replace the hot air escaping through the roof assembly.
Since you are not paying to heat your basement, the stack effect is not likely to impact your energy bill just because you have a cold basement but it may cause you to inject more heat into the living spaces than normal to maintain a comfortable temparature - which again may be where that extra 30% capacity comes in to save the day.