AHU Installation Method Statement

This document defines the method statement for the installation of AHU at construction site in compliance with the approved designs and approved material submittals.

Prior to installation of AHU, the supervisor and foreman will verify and ensure that all the safety requirements have been complied with and are in place.

All installation I Construction I Testing works shall be carried out  in compliance with the contract specifications and project health and safety manual.

Project Manager is the overall responsible for the implementation of the applicable methods and standards for AHU installation works.

The Construction Manager/Site Engineer will be responsible for all construction activities at the site and will directly supervise through erection work at site.

Site Engineer will be responsible for arranging and controlling the installation, inspection and testing activities.

Furthermore, it is the responsibility of each individual employee in the project to take due care to ensure their own personal safety and of their work colleagues.

Installation of Air Handling Units

Unless otherwise specified, all installation shall be in accordance to approved shop drawings and contract specifications.

Drawing plans, schematics, and diagrams indicate general location and arrangement of AHU’s.

Install AHU’s as indicated unless deviations to layout are approved on coordination drawings.

Examine areas and conditions with requirements for installation tolerances and other conditions affecting performance, operation and maintenance of AHU.

Check the AHU foundation and ensure it is as per approved shop drawings/builders work drawing.

Check the area around the foundation and ensure sufficient access to the Air Handling Unit from all sides.

Ensure availability of sufficient slope to the drain pipe, for easy draining of condensate drain.

Marking of AHU position shall be made on concrete plinth while referring to the center lines and reference points from architectural members such as walls, columns or gridlines based on approved construction drawing.

All AHU’s shall be installed horizontally and parallel to architectural lines, and placed in position based on markings.

Site Engineer shall ensure that the installation of Air handling Unit is carried out in accordance with manufacturer’s installation recommendation and specification.

Transfer the AHU’s from the stores to the working area, taking into account the make, model, capacity, and tag number, this will ensure the correct AHU is installed at the correct location.

The supervisor I foreman will ensure that the subject areas are ready to receive the AHU’s. Concrete plinths and rubber pads must be completed prior to the installation of the AHU.

Arrange the installation of AHU components according to the approved shop drawing, making sure that the units are correctly oriented, with sufficient access I space for operation and maintenance purposes.

AHU will be lifted using non-metallic slings, this must be used in conjunction with lifting frame I beam to ensure even load distribution and correct positioning of slings

Carefully move the AHU using a crane, block and tackle and or personnel (dependent on weight, size, and location) to the location and lowered onto the base in such a way that  the unit base bolting holes directly fit on the pre-installed anchor bolts.

Prior to this check the spring isolators for correct deflection.

Check the level of the unit using spirit level and firmly tighten the anchor bolts.

For AHU which are sectioned, these must be aligned and jointed firmly in accordance with manufacturer’s recommendation, AHU manufacturer to certify that the unit assembly is acceptable.

Upon satisfactory positioning of AHU’s, any open air/water outlets of AHU’s shall be closed properly and unit shall be checked & cleaned from debris and should be covered with polythene sheet to secure & protect it from moisture and dust ingress until the units are available for commissioning.

Connections to Air Handling Units AHU’s

Connect the ductwork to the unit using flexible connections of full size of the equipment to avoid the transfer of vibration into the building structures as specified.

Connect all the piping requirements as specified. Drawings indicate the general arrangement of the piping, fittings, and specialties.

Connect the piping as follows:

Install piping adjacent to the machine to allow service and maintenance.

Provide flexible duct connections between the air handling unit & ductworks, and provide proper support to ensure that the weight of the duct shall not act on AHU panel.

Connect condensate drain to indirect waste pipe. Install condensate trap of adequate depth to seal against the pressure of fan. Install cleanouts in piping at changes in direction.

Connect wiring as per the procedure of Low-Voltage Electrical Power Conductors and Cables.

Ground the Air Handling Unit as per the procedure of Grounding and Bonding for Electrical Systems.