选择HVAC系统
大家好，希望对HVAC提出一些意见，以进行我的翻新。刚刚获得了通过Energy Vanguard完成的手动J负载计算，但是让它们坚持设备选择 /管道设计，因为我有一些我想考虑的选择 - 但是现在我无法下定决心！
The house is 2-story with full basement, and I’m doing extensive work on the first and second floors; the basement sucks but fixing it is a later phase of this project (read: probably a couple years down the road). 2nd floor has 2 bedrooms, laundry room, bathroom, and an open hallway / study / staircase area — heating load 10k BTU/h, cooling load 5k BTU/h; interior completely gutted. 1st floor has 2 bedrooms, bathroom, and an open-ish living / dining / kitchen/ traffic circulation area, also open to the 2nd floor staircase — heating load 16k BTU/h, cooling load 10k BTU/h. Basement adds another 10k BTU/h heating load and no cooling load.
计划1：My initial idea was a ducted mini-split serving the second floor; based on these calcs it could be probably be the smallest (9k) Fujitsu Halcyon unit. A second ducted unit located in the basement could serve the basement and first floor — though I’m not sure of the implcations of either (a) sizing it for the full current load, but then insulating the basement later, or (b) undersizing it and just letting the basement be cold.
计划2：The 1st floor bedrooms, bathroom, and hallway sum to ~3.5k BTU/h heating load. The remainder of the first floor would then be close to 12k BTU/h heating load. That tempts me to (a) make the 2nd floor ducted unit a Fujitsu 12k unit and also serve the two first floor bedrooms (BUT the ductwork would be quite challenging if even possible) and (b) use a 12k ductless unit for the remainder of the first floor, centrally located in the basically open area. The basement gets neglected in this plan, and the ductwork for the 1st floor bedrooms might not be possible, but it is semi-tempting.
Plan 3:这里的通配符是,我有一个2.5 -ton-ish窟er-source heat pump unit in my garage. It’s a Climatemaster Tranquility single-stage unit that I got new but super cheap at a surplus place — BUT it’s a commercial 480V 3-phase unit that I got running with a transformer and a VFD from the same industrial surplus place (the VFD *might* let me fake multi-stage or continuously variable capacity — but I’m not sure if its specific compressor would be OK with that). Anyway, unlike most geothermal installs, I already have the unit and would DIY most of it, but I’d still need to have the outdoor part installed — due to not wanting to kill all my trees, I’d either need to go vertical wells or directional boring.
So, I have three (or more?) potential plans, all of which will cost several thousand dollars (either buying air source heat pumps, or paying for the ground-source wells / directional boring install), and all of which are complex in varying ways. I think my original plan has overall the most straightforward ducting, but plan 2 is tantalizingly elegant. Plan 3 mostly justifies my impulse buy of a commercial surplus heat pump
GBA Detail Library
由气候和房屋部分组织的一千个建筑细节的集合
答复
The drilling is typically the lion's share of the cost of a ground-source system.
Designing drilling and installing the pumps is lion's share of the cost of a ground-source system.
You may find this forum helpful it is dedicated to ground source HPs.
https://www.geoexchange.org/forum/
The skeptic in me suspects when people say how little it cost to run a ground source system they conveniently forget to include the cost for running necessary the water pumps.
当我看到他们在暖气季节结束时发布循环温度时，它们似乎总是距离销售距离的55°远低于32°。
Walta
我将投票计划1.使用这些单位，我将尽力使管道尽可能简单。您的设计温度是多少？您需要底板加热器吗？
Sorry, forgot to mention Zone 5 / near Cleveland, OH. Design temp used for the Manual J was 10F. Would need a cold climate unit with a base pan heater from my understanding.
我认为，您是否需要底板加热器处于边缘。我知道使用底板加热器知道的唯一小1：1的小型迷你拆分是载体（MIDEA）。我住在第5区（密歇根州，设计温度5F）。我有一个楼上的富士通（没有锅加热器，没有1：1的选择），但是我在一楼有一个无管（带锅加热器），实际上可以加热整个房屋。楼上的单元实际上在夏天使整个房子冷却。
Hm, your setup sounds like my plan 2 -- maybe your first floor is more open than mine is? what do your loads & room layout look like? Do you have a basement?
我只是意识到室外的差异：室内单元配对 - 我天真地认为只有一组室外单元可以与任何室内单元配对 - 所以我能够获得寒冷的气候带有导管室内单元的版本。我专门查看了富士通单元，因为它们的加热能力大大比冷却能力大得多，这似乎是我的负载条件更好的匹配。
虽然我的设计温度为10F，但有时我们有几天的极性涡流单位温度。记录低约为-20F，但低于零的温度很少。
I wonder if a modified Plan 2, with a ductless (ie 12LZAH1) on the first floor and ducted (9RLFCD?) on the second floor, leaving the first floor bedrooms (actually more likely to be used as guest room / office / misc kids stuff type rooms) to fend for themselves, possibly with a bit of supplemental resistance heat -- or incandescent bulbs, the heat load for the larger of the rooms is only 500W. Not sure of the implications of leaving the basement chilly... A third mini-split seems excessive though.
My house is a 30x40 2 story rectangle with full basement. Basement is insulated but unheated (never gets below 60 F). My first floor is completely open except for a half bath and laundry room. I have a 15k Fujitsu cold climate floor mount. Open stair way to upstairs which has three bedrooms and 2 bathrooms. I have a 12 Rlfcd with one register in each bedroom. BTW there is very little difference between the 9 and 12 rlfcd.
I would give the Carrier units a hard look. They are rebranded Mideas which is one of the largest HVAC equipment companies n the world. At least where I live there are way more contractors that carry Carrier than Fujitsu. I am also not thrilled with Fujitsu’s “thermostats”. The units work great, the controls leave something to be desired. I imagine the Carrier units would be more similar to a conventional thermostat at minimum I bet they are better than Fujitsu.
Given a chance to try again, I would have gone with a ducted Carrier on each floor.
Hmm, if your first floor is basically open, what would be your motivation for going ducted rather than ductless?
我会仔细研究一下运营商的产品 - 他们并不是真的在我的雷达上，因为每个人似乎都经常谈论富士通，三菱和戴基。
除了我已经提到的控件问题外，实际上有两个原因。1）使用管道单元，您有一个标准的一次性空气过滤器。无管头将需要一部分并在一定间隔清洁。2）当我确实将房屋出售时，大多数买家就更容易理解和接受。
更新：刚打电话给EnergyVanguard。忘了对基础加热器的意见提出意见，但听起来最有意义的是计划1-所有管道系统。即使考虑到我大部分开放的一楼平面图和高于平均水平的信封，他们也担心它的散布足以使一个无管的单元无法充分分发空气，以便在该空间中舒适 - 更不用说在一楼的卧室里了。我对无管道的主要吸引力是易于安装 /不必处理管道的优雅，但听起来好像有太多的妥协。当我制定最终计划时，将再次更新后代，但这似乎是我前进的方向。