GCT: an enterprise HVAC catalogue on a headless architecture
How we built the platform for a 25+ year authorised Haier distributor: a catalogue of ~58 models across 5 categories, from residential air conditioning to 2080 kW chillers, with a B2B quote-request flow and a configurator — on Next.js 15 + Payload, in a monorepo with Haier-AC.
25+
years as an authorised Haier distributor
≈58
models in the catalogue
5
product categories
2080 kW
industrial system capacity
The challenge: a large technical catalogue, three audiences
GCT has been an authorised Haier importer and distributor in Romania for over 25 years, covering the full HVAC spectrum: residential air conditioning, commercial systems (ceiling cassettes, floor-standing units), multi-zone VRF and industrial chillers. The challenge: a large, heterogeneous technical catalogue, with three distinct audiences — residential, commercial, industrial — that has to be presented clearly, with engineering specifications, and converted into quote requests, not into direct sales.
In other words: a platform that has to be both approachable for a residential customer and technical enough for a 2080 kW industrial project. Exactly the case where a simple website isn't enough and you need an enterprise platform with a manageable catalogue.
The solution: a headless, manageable architecture
We built the platform on the same enterprise architecture as Haier-AC, in a shared Turborepo monorepo: Next.js 15 with React Server Components, Payload CMS to manage the catalogue, Neon PostgreSQL for data and Cloudflare R2 for media. The distributor manages its own range, without code, and conversion happens through a sized quote request.
The catalogue is structured across five categories and segmented into the three audiences. Every model has a product page with real specifications — energy class up to A+++, capacity in kW, model codes and technologies. For the industrial segment (VRF with up to 64 indoor units, modular chillers from 65 to 2080 kW), the flow isn't a checkout but “Request a quote” / “Request sizing” — matched to a technical sales cycle.
Plus an air-conditioning configurator
Inside the platform we also built a Haier configurator: the user picks the building type (offices, hotel, clinic, warehouse, retail) and the floor area, and the tool calculates the required capacity based on cooling and heating coefficients (W/m²) and recommends the right modules from the Haier range — including the modular chillers for industrial projects. System coverage is visualised floor by floor, then it feeds straight into the quote request.
It's exactly the “configurator for a technical category” pattern: the customer doesn't have to become an HVAC engineer, they're guided to the right solution.
What GCT demonstrates
- 01
Headless scales with complexity
A catalogue with three audiences and capacities from residential kW to 2080 kW industrial — manageable without code, presented clearly. That takes full-stack, not a website.
- 02
Architecture follows the business
A quote-request flow, not a checkout — because B2B HVAC selling is technical. The platform was built around the real sales model.
- 03
Monorepo = compounding delivery
The second platform in the Haier ecosystem, shipped faster by reusing components from the monorepo. Enterprise quality, lower cost and time.
Frequently asked questions
What stack did the GCT platform use?
Next.js 15 with React Server Components, Payload CMS (headless, self-hosted), Neon serverless PostgreSQL, Cloudflare R2 for images and video (WebP/AVIF + MP4), inside a Turborepo monorepo shared with the Haier-AC platform, deployed on Vercel/edge. A headless enterprise architecture, chosen for a large, manageable technical catalogue.
What does the catalogue cover?
Five categories — air conditioning, heat pumps, chillers, ceiling cassettes and floor-standing units — around 58 models, segmented across three audiences: residential, commercial and industrial. Every model has a product page with real specifications: energy class (up to A+++), capacity in kW, model codes and technologies (Self Purify / IFD, UV-C PRO, Self Clean, Wi-Fi). For the industrial segment, VRF systems with up to 64 indoor units and modular chillers from 65 kW to 2080 kW.
Why a quote-request flow and not a classic checkout?
Because B2B HVAC distribution involves technical sizing and quoting, not a direct sale from a cart. Conversion happens through “Request a quote” and “Request sizing” — a lead-gen flow suited to the real sales cycle, especially for industrial projects where every installation is calculated. The business model dictated the architecture, not the other way around.
How did the monorepo shared with Haier-AC help?
GCT is the second platform in the Haier ecosystem built by Websem, after Haier-AC. Because they were developed in a shared Turborepo monorepo, the common components and logic were already written — so the second platform shipped significantly faster and cheaper, with the same enterprise quality. That is exactly the monorepo's economy of scale: every new platform is an extension, not a project from scratch.
What does the GCT platform's configurator do?
The user picks the building type (offices, hotel, clinic, warehouse, retail) and the floor area, and the tool calculates the required capacity based on cooling/heating coefficients (W/m²) and recommends the right Haier modules — including the modular chillers for industrial projects. System coverage is visualised floor by floor, and at the end it feeds straight into the quote request. The configurator turns a complex technical decision into a guided flow.
Conclusions
GCT shows how you build a platform when the catalogue is large, technical and manageable, and the sale is B2B: a headless architecture on Next.js + Payload, a catalogue managed without code, a quote-request flow matched to the real cycle, plus a configurator that guides the decision. And, through the monorepo shared with Haier-AC, it shipped faster and cheaper than a project from scratch.
It's exactly the kind of platform the enterprise stack exists for — and exactly the case where a simple website wouldn't have been enough. The question for your business: is your technical catalogue presented as a manageable asset, or locked into a website you can't manage yourself?
Dan Cristian Alexandrescu is the founder of Websem, an agency that builds enterprise platforms on Next.js + Payload, in a monorepo. The Websem team delivered the Haier platform ecosystem (GCT, Haier-AC) and platforms for Eurial Selection, ChinaCars.Global and other brands.
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