Writing an Industrial HVAC Tender: Loads, Equipment Specs and Commissioning Tests

An industrial HVAC tender must carry a heat-load basis bidders can check, an equipment schedule with performance stated at rated conditions, a controls scope, a testing, adjusting and balancing (TAB) requirement, and commissioning tests with pass criteria. Without the load basis, bidders price different jobs. Without the test clauses, performance is a promise. Write the document so that bids are comparable and the plant can be proved on site.

What load basis goes into the tender?

Give bidders the inputs, not just the answer. For each zone state the process heat released into the space (equipment kW times a load factor and a diversity you can defend), the number of people, the lighting and small power, the solar and conduction gain through the roof and walls, infiltration, and the fresh air the zone needs. Add the indoor condition you require (temperature, relative humidity, and the tolerance on each), the cleanliness or pressure class if one applies, and the hours of operation. The National Building Code of India is the reference standard that the BEE's ECSBC 2024 names for HVAC and thermal-comfort conditions, so cite the edition you design to.

Fix the outdoor design condition from local climate data, and say whether you want margin for hot spells. Plants in north India are sized against very hot summer afternoons, and the condenser or tower must still reject heat then; see our note on HVAC design for 50 degree summers. Decide early whether the building needs process cooling or comfort cooling, since the cost and the technology differ; our guide to shopfloor cooling versus comfort HVAC sets out the choice. Run a first-pass plant size in the chiller capacity calculator and check the tender figure against it.

How do you specify the equipment?

Use an equipment schedule, with one row per item and the performance at the rated condition. The table lists what each row should contain.

For fans and motors the BEE code is a useful target even outside its scope: it asks for air-handling-unit fans of at least 65 percent mechanical efficiency with IE3 motors at the base level, 70 percent with IE4 at ECSBC Plus and 75 percent with IE4 at Super ECSBC. It covers commercial and office buildings and excludes manufacturing-process equipment, so treat those numbers as a benchmark, not a requirement. For the chiller itself, our chiller plant page shows what we scope, and the chiller plant cost drivers guide explains the efficiency trade-offs.

What testing and balancing must the contractor deliver?

TAB is the step that turns installed equipment into a working system, and it is the clause most often missing. ECSBC section 6.2.6 requires air and hydronic systems serving zones above 500 square metres to be balanced: air systems first to minimise throttling losses, then fan speed and register dampers adjusted to meet design flow at each outlet; hydronic systems balanced proportionally to minimise throttling, then the pump impeller trimmed or the speed adjusted to meet design flow. Write the same logic into your tender.

• Require a TAB report with design and measured values at every outlet, coil and branch, signed by the person who measured.
• State the tolerance on flow and temperature in the specification, and who decides if a point fails.
• Require calibrated instruments and the calibration certificates in the report.
• Consider an agency independent of the installer for large plants, so the person who measures is not the person who is paid to pass.
• Require duct leakage tests before insulation is closed; our note on duct leakage and air balancing explains the performance gap when this is skipped.

Which commissioning tests and documents belong in the contract?

The ECSBC commissioning appendix, which applies to buildings above 5,000 square metres and is voluntary, describes a process any plant can follow: the owner writes project requirements, the commissioning plan holds construction checklists and test procedures for each system, and it names the agency that performs each test and the agency that approves the result. The plan should include HVAC. Convert that into contract clauses:

1. Pre-functional checks on each item: alignment, rotation, filter fitting, refrigerant charge records, safeties.
2. Functional tests of every control sequence, including failure modes such as pump trip and power restoration.
3. Performance tests under load, with calibrated instruments, against the schedule values.
4. Seasonal or deferred tests where the full design load cannot be reached on the day.
5. Training for the operators, with a log of who attended.

The handover file should hold as-built drawings, equipment data sheets, the TAB and test reports, the control sequences and settings, the O&M manuals, the warranty terms and a spares list. Our guide to MEP commissioning and handover documentation and the glossary entry on HVAC commissioning list the items. Make the final payment, or a defined retention, depend on delivery of the file and the passed tests.

How do you compare the bids?

Ask every bidder to price against the same schedule and to list exclusions separately. Normalise the scope in a comparison sheet before you look at totals: missing items are the most common source of a low bid. Ask for the make and model of each major item, the lifecycle energy of the plant at your load profile, and the contractor's own commissioning plan. Check references for a plant of similar size and type. Our guide to what an HVAC contractor's BOQ should include and the MEP quotation comparison calculator give a structure, the HVAC RFQ template offers a document you can copy, and our guide to selecting an industrial HVAC contractor covers the prequalification.

How Secured Engineers helps

We design industrial and commercial HVAC in-house with the electrical, plumbing and fire design, so the plant room, power feeds, make-up water and fire protection are coordinated before the tender is issued. We file Fire NOC, CEIG and DISCOM applications in-house and deliver MEPF and solar under one contract. We work from offices in Noida (Delhi NCR) and Ludhiana, with 535+ projects across 18+ states and 89.77% repeat clients.

Send us your draft tender, the load calculation and the bids you have received, and we will review them line by line and tell you what is missing, ambiguous or not comparable. See our HVAC and mechanical page, message us on WhatsApp, call +91 70099 85817, or ask for a free proposal.