Specifying Steel Panel Radiators in an Engineering Tender: A Practical Checklist for Project Buyers

When steel panel radiators appear in an engineering tender — a residential development, a school, a district-heating retrofit — the radiator section of the specification is often either too vague ('steel radiators, white, various sizes') or copied from a catalog the drafter happened to have. Both cause problems: vague specifications attract bids that cannot be compared, while over-specific texts lock the project to one supplier and inflate cost. As a factory that regularly prices tender packages for projects in Europe, Russia, and Central Asia, here is what we would put in the radiator section if we were writing it — and what we look for when we respond to one.

Performance requirements: specify by EN 442 data, not by brand The core of a radiator specification is heat output, and the only meaningful way to state it is with the test basis: output in watts at ΔT50 per EN 442, and at ΔT30 if the project runs on low-temperature sources such as heat pumps or condensing boilers. State the required types (Type 11, 21, 22, or 33), the height and length ranges, and the connection layout (side or bottom). Add working-pressure and test-pressure requirements that match the system — a high-rise or a district-heating connection needs a higher rating than a two-story house. If you specify outputs without the ΔT basis, bidders can quote at ΔT60 or ΔT70 and look better on paper; a shared basis is what makes bids comparable. See our explainers on [EN 442 ΔT50/ΔT30](/en/blog/understanding-en442-dt50-dt30) and on [working vs. test pressure](/en/blog/radiator-working-and-test-pressure).

Documentation to require from every bidder A tender should list the documents a bidder must submit, not just the performance numbers. The practical set: a Declaration of Performance (DoP) for the offered models; EN 442 test documentation from the manufacturer supporting the declared outputs; GOST compliance documents where the project is in Russia or in Central Asia markets that require them; a factory quality-management certificate; and written warranty terms. Ask for documents tied to the specific models offered, not generic company brochures — and verify what you receive: check that the model names, dimensions, and declared outputs on the DoP match the bid line items. A supplier that hesitates to provide model-specific documentation before contract is telling you something.

Commercial and logistics clauses that prevent disputes later The technical section decides whether the radiator heats the room; the commercial section decides whether the project runs on schedule. Require bidders to state: production lead time for the tendered quantity (with staged deliveries if the site needs them), packaging specification for export transport, a container loading plan or shipped-quantity commitments, and the policy for replacing units damaged in transit. For projects with a branding requirement, confirm OEM labeling capability and the artwork approval steps in advance. These clauses cost nothing to include and remove the most common sources of dispute between the winning bidder and the project team.

How to compare bids — and the red flags When bids arrive, normalize before comparing: same type, same size, same ΔT basis, same delivery terms (EXW, FOB, or CIF change the picture significantly). Red flags worth taking seriously: outputs quoted with no ΔT basis; a price notably below the field with no explanation of construction (thinner steel or reduced convector fins are the usual reason); no DoP, or 'documentation available after order'; and vague lead times. A slightly higher unit price from a bidder with complete documentation and a realistic schedule is usually the cheaper bid by the end of the project.

JD Radiator (Tianjin Jiuding Yangguang HVAC Co., Ltd.) is a family-run manufacturer since 2002 and regularly prices tender packages for buyers in Europe, Russia, and Central Asia. Our panel radiators are EN 442 compliant with a Declaration of Performance available, and GOST compliance is held for the Russian market — model-specific documentation is provided at the bidding stage, not after contract. If you are preparing a tender or evaluating radiator bids, send the specification to lunan@jdradiator.com / kevin@jdradiator.com or call +86-22-69189950; the model range is at /en/products and certification details at /en/credentials.