Home / Chicago HVAC / Deljo Heating & Cooling

pilot · Chicago HVAC · September 2026 edition

Deljo Heating & Cooling

3 of 3 facts verified against a public register, as of 2026-09-03. On the record: verified against public sources and dated. We don't approve the booking. Named in 20 of 60 probe answers this edition (ChatGPT, Gemini and Perplexity) — an input, not a score.

Verified facts

Real business

Verified

2026-09-03 → 2026-12-02 · source

Deljo Heating & Cooling, Inc, — Regulated Business License, license number 2971994, term license_id 3082025, status AAI, issued 2026-07-24, expires 2028-06-15, City of Chicago business register

At that address

Verified

2026-09-03 → 2026-12-02 · source

4300 W BRYN MAWR AVE, Chicago, IL 60646 — registered address on the current licence term (term license_id 3082025), City of Chicago business register

Licensed

Verified

2026-09-03 → 2026-12-02 · source

Regulated Business License, license number 2971994, term license_id 3082025, status AAI, business activity "Heating, Ventilation and Air Conditioning Services - Residential"

Verified facts carry the date we checked, the date they expire, and the public source. A missing check is coverage, not a finding about the business.

Use your stamp

This seal is live. Wherever it is placed, it reads the record each time it is shown, says exactly what this receipt says, and links back to this page. When the record changes, the seal changes with it. Nobody can buy it and it costs nothing: it is the same instrument for every business on the record.

Today it reads VERIFIED · CHECKED 2026-09-03 · 3 OF 3 FACTS VERIFIED.

<a href="https://lodestarstamp.com/companies/deljoheating-com.html"><img src="https://lodestarstamp.com/v1/seal?domain=deljoheating.com" width="160" height="160" alt="Lodestar Stamp: Verified: 3 of 3 facts verified against a public register, checked 2026-09-03."></a>

Open the image

For a dark background add &ink=dark; for a larger file add &size=480. The alt text is generated from the receipt, so a screen reader hears the same fact. Machine-readable receipt data: /index.json and this page.

What assistants named this edition

Probe battery input, never a score. The same questions, the same edition, who was named.

ChatGPT Gemini Perplexity

Every answer that named Deljo Heating & Cooling this edition (10)

Verbatim lines from the checked-in capture files. Published battery questions only.

Q: Which HVAC companies in Chicago do people trust most?

Deljo Heating, Cooling & Plumbing — 4.9/5, ~3,440 reviews. A long-established Chicago option with a huge review base and 24/7 availability. One caveat: independent Checkbook data shows some complaints about price and service, so I'd get a written quote.

ChatGPT · Aug 11, 2026 · run chatgpt-r1

Q: 24/7 emergency furnace repair in Chicago

Deljo Heating, Cooling & Plumbing — 4.9★, 3,440 reviews — (773) 657-9989. Listed open 24/7 and handles emergency no-heat/furnace repairs.

ChatGPT · Aug 11, 2026 · run chatgpt-r1

Q: Schedule an HVAC maintenance visit in Lincoln Park for under $150

| Deljo Heating, Cooling & Plumbing | Local Lincoln Park HVAC seasonal maintenance and safety checks | Request quote to match budget | Call (773) 829-4295 |

Gemini · Aug 12, 2026 · run gemini-r1

Q: 24/7 emergency furnace repair in Chicago

Deljo Heating & Cooling — Phone: (773) 829-4295 [Deljo Heating & Cooling]; Services: Around-the-clock emergency diagnostics and repairs for furnaces and heat pumps. [Deljo Heating & Cooling]

Gemini · Aug 12, 2026 · run gemini-r1

Q: 24/7 emergency furnace repair in Evanston

Deljo Heating & Cooling — Phone: 773-829-4295 [Deljo Heating & Cooling]; Details: Over a century of experience servicing the Chicagoland area with 24/7 emergency HVAC technicians ready for dispatch. [Deljo Heating & Cooling]

Gemini · Aug 12, 2026 · run gemini-r1

Q: Which HVAC companies in Chicago do people trust most?

Deljo Heating & Cooling | 4.9/5 from 110 Carrier-hosted customer reviews; Chicago location on W. Bryn Mawr. | Carrier systems and established local service

Perplexity · Aug 11, 2026 · run perplexity-r1

Q: Which HVAC companies in Evanston do people trust most?

For Evanston, Illinois, the strongest local-trust candidates appear to be Flader Plumbing & Heating, Deljo Heating & Cooling, and Hero Air—but "most trusted" depends on whether you prioritize a truly local shop, volume of reviews, or emergency availability.

Perplexity · Aug 11, 2026 · run perplexity-r1

Q: Are the big HVAC chains in Evanston better than independent shops?

Some well-known Evanston-area providers marketed as larger firms include Four Seasons, Deljo, Hero Air, and other companies serving the broader Chicago/North Shore area. A local industry listing gives those firms strong reported ratings and availability, but because that information is promotional, treat it as a starting point—not proof that one is best for your house. [fourseasonsheatingcooling]

Perplexity · Aug 12, 2026 · run perplexity-r1

Q: Which Lincoln Park HVAC company has the best reviews for installations?

Other notable options: Cruz Air LLC — family-owned Chicago HVAC contractor, 5.0 stars from 54 reviews, serves Lincoln Park and surrounding neighborhoods. Deljo Heating & Cooling — repairs, installations, maintenance with 24/7 emergency service in Lincoln Park.

Perplexity · Aug 12, 2026 · run perplexity-r1

Q: 24/7 emergency furnace repair in Chicago

Deljo Heating & Cooling — 773-829-4295 — 24/7 emergency HVAC service throughout Chicagoland.

Perplexity · Aug 12, 2026 · run perplexity-r1

Can machines read their site?

AI crawler policyWhat robots.txt says about AI crawlers.

standard

llms.txtA plain-language file agents can read before guessing.

SitemapA machine-readable map of important URLs.

yes

Structured dataLocalBusiness JSON-LD or equivalent structured business facts.

yes

Agent endpointVerified JSON only; never an advertisement for tools.

none

Probed twice. 0 signals disagreed between the two passes.

Probe notes this edition

Publish a real /llms.txt that summarizes the business for AI agents.
State an explicit AI crawler policy in robots.txt for GPTBot, ClaudeBot, Google-Extended and PerplexityBot.
Optional: publish a verified agent card at /.well-known/mcp.json so assistants can transact with you directly.

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Watching · one business · First month free, then $149/month

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First month free

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Then $149/month · USD · automatically renews until canceled. 14-day refund on the first paid invoice. Cancel future renewals by email.

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Monthly readout for your selected business covering the previous month
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Weekly digest for your selected business covering the previous week
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This receipt is free and it is not for sale. We do not sell the fix, and no payment moves this record, not from this business and not from whoever markets it. Send corrections with evidence to watch@lodestarstamp.com. Clocks and filed records: /corrections.html.

Where to next

Chicago HVAC record

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