AHU组件：风机、过滤器与回热芯体

Anatomy of an Air Handling Unit

An AHU conditions outdoor air before it enters a building. The core components are: the supply fan, the exhaust fan, filters, coils (heating/cooling), and – increasingly – a heat recovery core. How these are arranged decides both air quality and energy use.

Fans

送风机与排风机驱动空气流动。它们的效率以及 压降 经由各部件共同决定风机功率。增加 100 Pa 压降的回收装置，可能悄然使能耗上升 10–20%。

Filters

过滤器保护居住者与盘管。等级从粗效（ISO Coarse / MERV 8）到高效（ePM1 / MERV 13+）。更洁净的空气意味着更大的压降，因此过滤器选择与热回收布置必须统筹平衡。

The recovery core

The recovery core – 板式, 转轮式、热管、或 run-around coil – sits between the two airstreams. In a new build it is designed in; in a retrofit it is added to the exhaust riser (see 改造指南).

Sizing the whole unit

热回收必须与 AHU 统筹选型，而非事后加装。请使用我们的 AHU 选型计算 以便在订购前平衡有效度、压降与风机能耗。

Coils and the recovery interaction

Heating and cooling coils sit on either side of the recovery core, and their duty shrinks as the core pre-conditions the air. Sizing coils on unrecovered design conditions wastes capacity and cost, while sizing them on recovered conditions lets the core do the first stage of work. The coil and core should be specified together so the plant is neither oversized nor starved at part load.

Controls and sequencing

The air handling unit controller ties fans, filters, coils, and the recovery core into one sequence. A well-written sequence modulates the core and bypass, trims coil output to the recovered air temperature, and protects filters and fans from overload. Poor sequencing can leave the recovery core fighting the coils, eroding the very savings it was installed for.

Commissioning the whole unit

Recovery only pays when the assembled air handling unit meets its spec as a system. Commission by measuring supply and exhaust airflow, the temperature rise across the core, and the total pressure drop, then comparing against the AHU selection calculation. Trend these values so filter loading, belt slip, or core fouling shows as drift rather than a sudden complaint. Balance effectiveness, pressure drop, and fan energy before sign-off.

常见问题

What are the main AHU components?
The supply and exhaust fans, filters, heating and cooling coils, and increasingly a heat recovery core.

How does the recovery core interact with coils?
It pre-conditions the air, shrinking coil duty, so size coils on recovered conditions rather than unrecovered design conditions.

Why size recovery with the whole AHU?
Bolt-on recovery can raise pressure drop and fight the coils. Integrated sizing balances effectiveness, pressure drop, and fan energy.

How do I verify AHU performance?
Measure supply and exhaust airflow, the core temperature rise, and total pressure drop against the AHU selection calculation, and trend for fouling.

常见问题

What are the main AHU components?

The supply and exhaust fans, filters, heating and cooling coils, and increasingly a heat recovery core.

How does the recovery core interact with coils?

It pre-conditions the air, shrinking coil duty, so size coils on recovered conditions rather than unrecovered design conditions.

Why size recovery with the whole AHU?

Bolt-on recovery can raise pressure drop and fight the coils. Integrated sizing balances effectiveness, pressure drop, and fan energy.

How do I verify AHU performance?

Measure supply and exhaust airflow, the core temperature rise, and total pressure drop against the AHU selection calculation, and trend for fouling.