在地下室整理过程中HVAC计算应该在现有的家中运行吗？
早安GBA社区，
I’m finishing my basement and converting the crawlspace from vented to unvented. I am curious about whether as part of the project I should have whole house Manual J, S, and D calculations run to inform the HVAC design. I have read here that most HVAC subs will opt to use a rule of thumb on sizing for ducts and the system overall which leads to less than optimum system sizing and duct placement (particularly on return).
该房子是1977年北弗吉尼亚州（CZ 4）的建设，单层，2300成品SQFT在主层面，其中1300平方英尺在地下室完成，约1000平方英尺的爬行空间。热泵室内机位于沿着爬行空间的直喷式行李箱线，在主级别耗尽到室内边缘寄存器。运行是绝缘的，但行李箱不是。树干上没有可辨别的密封。我没有退回跑步上的绝缘，看看是否有任何密封。地下室中的线条具有更多的弯曲，以使它们到往上楼的寄存器，这些寄存器主要在室边。地下室部分中的所有运行都是绝缘的，所以我还没有完成任何密封（胶泥或胶带），但我不能看。一个中央回物几乎直接坐在主机上方，直线下降。有返回压力问题（它有点迷人，当热量打开时，我们的卧室门独自关闭！ - 我将用荷兰克的门内返回空气通路来解决这个问题。
Here’s my plan, subject to your criticisms:
1. Purchase either through HVAC sub or independent entity, a set of whole-house Manual J, S, and D calculations and optimal design for new supply and return runs for basement space being finished and new supply to crawlspace, as well as recommending any changes to existing ducts supplying finished area of house.
2.尽可能用RCD＃6乳香，厚度作为镍和玻璃纤维网带，在需要的情况下，密封爬行空间。
3.为新的地下室管道指定，HVAC副使用刚性管道在最大程度上，接头螺纹和接缝和接缝用乳香厚作为镍，所有供应绝缘至R-8。
4. Have HVAC sub or another party perform duct blaster testing, then aeroseal, then duct blaster testing to address leaks in the existing system that I can’t get to with mastic.
我担心HVAC Sub是否可以/将运行手册J / S / D计算的设计 - 如果我搜索独立的公司来做这件事吗？作为一个说明，我正在通过一个GC，所以他与一组HVAC潜艇有关系，他通常使用，我不知道是否在设计前进行计算。
开火！谢谢你的想法。
埃里克斯
GBA详细资料库
A collection of one thousand construction details organized by climate and house part
Replies
正确完成的地下室增加了很少的加热，几乎没有冷却负载（有点潜冷，有时还需要除湿机）。
如果您的炉子提供楼上的楼上，那么真的无需去螺母并重新剥离设置。有时将主干置于天花板高度但看起来并不像你一样有意义。
您需要在地下室和爬网空间中添加正确的大小电源和返回寄存器。
Insulating and air sealing ductwork is important when it is outside the conditioned envelope (in attics or vented crawlspace).
随着现在在内部有条件的空间，导管的绝缘无关紧要。任何损失都有留在热封内，所以它们不会迷路。空气密封回归仍然是一件好事。采用适当的过滤器烤架和密封良好的回报，您的导管将保持闪亮清洁。
空气密封供应不会受到伤害，但不需要覆盖。
是的，但也没有。它听起来不像你改变设备或运行所有新的导管，所以传统意义上的设计并不是你需要的。来源：我是HVAC系统设计师。
我所做的在改造现有的管道系统s: Start by visiting the site and measuring the existing system. System static pressure, airflow from all the registers, total airflow, delivered air temperatures, duct sizes, etc. I also collect information for a heat gain/loss calc. I talk to the customer to try and determine any existing comfort issues, like cold/hot rooms or slamming doors, how long the system seems to run during hot/cold times. This tells you how a system is actually performing, which is the most important thing for an existing system.
You do the heat loss/gain calc to ensure the equipment has enough capacity (10/10 so far it is way oversized) and then you give them a list of things to improve the system, like adding additional registers to uncomfortable rooms and fixing return issues, upsizing any ducts that are too small, repair any damage ducts you might have observed, airsealing existing ducts, maybe insulating long lines, balancing ductwork, etc. If you bring a good hvac tech along, he can check out the equipment and tell you if now is a good time to change it out or if it still has lots of life left. That's the process that should be taken. Measuring the existing system performance is key to a good retrofit design.
Thank you Akos & Yupster. I appreciate your thoughts. I will make sure they measure the current system performance and ensure they plan in supply and return that makes sense for the new parts in the basement.
Eric