How to judge whether the MAU chemical filtration section is arranged before or after the surface cooler?

Whether the MAU chemical filtration section is placed before or after the surface cooler should be determined based on the target pollutants, allowable temperature and humidity of the medium, liquid water risk, and front and rear particle protection. The response of different media to humidity is not consistent. 'Low temperature after the coil' cannot simply be regarded as a favorable condition for all chemical filtration.

Calculate clearly the state of the air that the medium actually contacts

Before the coil, it may be subject to outdoor high temperature, high humidity and dust changes, while after the coil, it may be close to high relative humidity, and there is a risk of condensation water carrying. If there is reheating later, the temperature and humidity of the gas when it contacts the medium will change again. The range specified in the media data should be checked and it should be clarified whether droplets or long-term moisture exposure are allowed.

Before coiling, check the outdoor fluctuation, pre-filtration and pollutant load; after coiling, check the relative humidity, water content and necessary follow-up treatment; for other positions, re-judge according to the true state after reheating or mixing. The three types of positions correspond to different air conditions, and you cannot just compare the temperature. For the adsorption and chemical reaction mechanism of chemical filters, please refer toWhat is the difference between adsorption and chemical reaction in chemical filters?。

Considerations for layout before coiling

When arranged in front of the coil, the chemical filter section faces uncooled air, and the temperature and moisture content may be higher, but there is generally no droplet carrying problem behind the coil. A pre-coil arrangement may be appropriate if the target contaminant concentration is high or needs to be removed before entering the coil. However, high temperature and high humidity environments may affect the capacity and life of some media, and the applicable conditions for the media need to be checked.

Outdoor air fluctuations and dust loads also need to be considered, please refer toCan the MAU chemical filter be placed in the outdoor air inlet box? . How to protect chemical media with pre-filtration configuration, please refer toHow to configure the primary-efficiency and medium-efficiency filters of air-conditioning boxes in different stages?。

Considerations for post-coil layout

When arranged after the coil, the chemical filter section faces the cooled air, which has a lower temperature, but the relative humidity may be higher, and there is a risk of condensation water carrying. If the medium is good for low temperature but sensitive to high humidity, the post-coil arrangement may not be appropriate. It is necessary to confirm whether there are water blocking or water removal measures behind the coil, and whether the medium allows a high relative humidity environment.

Coil head-on wind speed and water risk, please refer toWhat impact does the coil head-on wind speed have on heat exchange and water entrainment in the air conditioning box? . For water tray and drainage conditions, please refer toHow to combine the slope of the water pan of the air-conditioning box with the layout of the drain outlet? . If there is reheating after coiling, the state of the air in contact with the medium will also change.

Different media have different humidity responses

Adsorbent media and reactive media may respond differently to humidity. Some adsorbent media lose capacity at high humidity, some reactive media are sensitive to moisture, and some media perform better at low humidity. The humidity applicable range of one medium cannot be extended to all chemical filters.

The significance of low outgassing chemical filter materials for sensitive processes can be referred toWhat are the implications of low outgassing chemical filter media for sensitive processes? . Whether the chemical filter material will bring particles to the downstream, please refer toWill chemical filter materials bring particle pollution downstream?。

Particle protection and sequence should be checked together

Whether particle filtration is installed before and after the chemical filtration section will affect the dust accumulation on the surface of the chemical media and the cleanliness of the downstream. Particle pre-filtration is placed before the chemical section to reduce dust deposition; whether particle filtration is required after the chemical section depends on the medium's own release and downstream requirements. The combination method of chemical first and then particles is widely used on the equipment side. Please refer tochemical filter FFU .Configuration ideas of

How to determine the order of function segments, please refer toOn what basis should the sequence of functional sections of the air conditioning box be determined? . How to form internal resistance, please refer toWhat functional segments should be included in the internal resistance of the air conditioning box?。

After the location is determined, the maintenance path must be verified.

The chemical filter section needs to retain replacement space and necessary monitoring positions. Additional filtering or waterproofing measures will increase resistance. During technical confirmation, the air flow, status of each section, and applicable media information should be provided at the same time. You cannot just reserve an abstract position on the floor plan. Life assessment should also use actual operating conditions at the location.

How to judge replacement after partial penetration of chemical filter, please refer toAfter the chemical filter is partially penetrated, how to determine whether to replace the entire set or replace it in layers? . The reason why the chemical filter fails soon after it is replaced can be referred toWhat is the reason why the chemical filter fails soon after it is replaced?。

Aili industrial supporting equipment

Aili Industrial can check the structural interfaces in combination with chemical filtration, coil and box layout; the project party provides target objects and segmented air conditions to help select a reasonable location. Aili's industrial manufacturing end covers the independent research and development and production of motors and fans, control systems, sheet metal, air filters and complete machine assembly. The chemical filter section, surface cooler and box structure can be matched in the same package; non-standard layout can be adjusted according to the on-site air flow.

Product form can be viewedAir handling unit andFan box page; chemical filtration scheme can be viewedChemical filter page; clean air supply package can be combinedFFU fan filter unit andEFU equipment end fan filter unit verification; terminal particle filtration can be combinedHEPA/ULPA filter confirmed. The specific layout, filtering effect and delivery scope still need to be verified based on the corresponding configuration data and on-site working conditions. The actual results are subject to on-site leak detection and gas detection results.

Submit project parameters:https://ailigy.com/contactus.html

Related questions and answers

Is it necessarily better to place the chemical filtration section after the coil?
uncertain. The temperature after coiling is lower but the relative humidity may be higher, and there is a risk of water contamination. Whether it is suitable depends on the response of the medium to humidity.

What should I pay attention to when arranging the coil?
The air in front of the coil is uncooled, and the temperature and moisture content may be high. It is necessary to check the applicable conditions of the medium and consider outdoor fluctuations and dust load.

Can Aili Industrial help determine the location of the chemical filtration section?
The location and structure can be checked based on the target pollutants, medium conditions and segmented air conditions. The specific plan needs to be confirmed based on product information and on-site working conditions.

Related articles

1. What is the difference between adsorption and chemical reaction in chemical filters?

2. What impact does the coil head-on wind speed have on heat exchange and water entrainment in the air conditioning box?

3. On what basis should the sequence of functional sections of the air conditioning box be determined?

4. Will chemical filter materials bring particle pollution downstream?

Key points for selection and acceptance inspection