Superheat Calculator

Free, inside your AI assistant

Make your AI get the code right

Connect Intry to Claude and your AI stops guessing at the numbers. Ask any wire, load, conduit, or refrigerant question in plain English and get the real code-accurate answer, what it means, and the cited source, computed live, right on your phone.

Add Intry to ClaudeSee what it can do
The difference: ask a plain AI “what size wire for a 48A EV charger?” and it answers from memory, and it is wrong often enough to fail inspection. Say “use Intry to size a 48A EV charger” and it runs the real calculator: #6 Cu on a 60A breaker, with the verdict and NEC Article 625 cited. Same easy question, an answer you can actually install.

Add Intry to Claude in about 30 seconds

Copy the link, paste it into Claude, and start asking. It works in the phone app too.

Add Intry to ClaudeOpens Claude with Intry already filled in.
  1. Claude opens with the Intry connector already filled in. Review it and click Add.
  2. (If a field is blank, paste the link below into the URL field.)
  3. In any chat, tap + then Connectors and switch Intry on. Then name Intry in your question (“use Intry to…”) so Claude runs the tool instead of guessing.
https://www.intrysys.com/api/mcp

No login, no API key, and it works on every Claude plan, right from your phone.

The one rule: name Intry in your question. Say “use Intry to…” or start with “Intry,” and (with the connector switched on for that chat) Claude runs the real calculator. Leave Intry out and Claude answers from its own memory, which is the guesswork you are trying to replace.

What you can ask it to run

Intry’s most-used field calculators, all runnable from a plain-English question. Each one answers with the number, a verdict, and the cited source. Open one for example questions.

CalculatorTradeAnswers questions like
Voltage Drop CalculatorElectrical“Use Intry to check the voltage drop on a 120 ft run of #10 copper at 20 A, 240 V.”
Wire Size CalculatorElectrical“Use Intry to size the copper wire and breaker for a 50 A continuous load.”
EV Charger Circuit CalculatorElectrical“Use Intry to size a 48 A hardwired EV charger: wire, breaker, and ground.”
Conduit Fill CalculatorElectrical“Ask Intry if nine #12 THHN fit in 3/4 inch EMT or I need to go up a size.”
Box Fill CalculatorElectrical“Ask Intry if a 4 inch square box holds six #12 with a receptacle and grounds.”
Superheat & Subcooling CalculatorHVAC“Use Intry: R-410A, suction 118 psig at 55F line temp, liquid 340 at 90F. Superheat and is the charge right?”
MCA & MOCP Breaker CalculatorElectrical“Use Intry to size the wire and breaker for a condenser with MCA 24.5, MOCP 40.”
A2L Line Set CalculatorHVAC“Ask Intry if I can reuse my R-410A line set for a new 3 ton R-454B system, 40 ft run.”
Existing-Load Panel Check (NEC 220.87)Electrical“Ask Intry if a 200 A service with a 110 A utility peak can take a 48 A EV charger.”
Conduit Offset Bend CalculatorElectrical“Use Intry for the marks and shrink on a 6 inch offset at 30 degrees in 3/4 inch EMT.”
Saddle Bend CalculatorElectrical“Use Intry for the marks and shrink on a 3 inch deep 3-point saddle at a 45 degree center bend.”
Water Heater Circuit CalculatorElectrical“Use Intry to size the circuit for a 4,500W 240V heat pump water heater: wire, breaker, and ground.”
120V Induction Range Circuit CalculatorElectrical“Ask Intry if a 15 A plug-in induction range (Impulse or Electra) can share a 15 A kitchen circuit or needs its own.”
Biggest EV Charger Calculator (NEC 220.87 + EVEMS)Electrical“Ask Intry for the biggest EV charger a 100 A service with a 60 A measured peak can take.”
Solar Backfeed Breaker Calculator (NEC 705.12 120% Rule)Electrical“Ask Intry how big a solar backfeed breaker a 200 A panel with a 200 A main can take under the 120% rule.”
Cold-Climate Heat Pump Capacity CalculatorHVAC“Use Intry to find the Mitsubishi Hyper-Heat heating capacity at 5F and how much it holds versus its rated 47F.”
A2L Refrigerant Charge Limit CalculatorHVAC“Use Intry for the maximum R-454B charge in a 200 sq ft room with a ceiling cassette.”
Manual J Residential Load Calculator (ACCA 8th Edition Form J1)HVAC“Use Intry to run an ACCA Manual J load for a 2,000 sq ft, 3-bedroom house on the NEW CASTLE, Delaware design conditions.”
Outdoor HVAC GFCI Requirement (NEC 210.8(F))Electrical“Use Intry to check whether an outdoor condenser needs GFCI protection in Georgia after 1 September 2026.”

Why the answers hold up

Every Intry result, on the site or through your assistant, meets one standard we call Intry Verified: the same four provenance facts on every answer, and a deterministic gate that re-derives the calculated numbers from their locked source and re-checks them on every deploy.

Computed, not remembered

Every answer comes from the same calculator you use on this site, and every build re-derives those numbers from the locked source modules, so you can see exactly where each one comes from.

Tells you what it means

Not just a number, a verdict on the readings that call for one (within 3%, upsize the wire, over-fill, undercharged), plus the cited source behind it.

No cost, no setup

No login, no API key, and it runs on every Claude plan, on your phone. One paste and your assistant has it for good.

Built for the trades

NEC 2023 electrical and the R-454B / A2L refrigerant transition for HVAC, from the field calculators techs already use.

Keep the readings. Ship the job.

Claude runs the numbers. Only the Intry app keeps them as one job, and one tap ships the whole job back to your AI for the next steps to finish it. Works offline.

Frequently Asked Questions

What does this actually do?

It gives Claude (and other AI assistants) the ability to run Intry's real field calculators instead of guessing. Once connected, you ask a question that names Intry, like 'use Intry to size a 48 amp EV charger', and Claude runs the actual code-accurate calculator and answers with the number, a verdict, and the cited source it came from. It is a new way to run the numbers: no punching inputs into a calculator, just ask mid-job and get the answer and what to do next.

How do I make sure Claude actually uses Intry and not its own guess?

Name Intry in your question. Say 'use Intry to...' or start with 'Intry,'. With the connector switched on for that chat and Intry named in your prompt, Claude runs the real tool and cites the source. If you do not mention Intry, Claude may answer from memory, which is the unreliable guesswork this exists to replace. Turn the connector on per chat with the plus button, then Connectors, in the message box.

Is it free?

Yes, completely. Intry costs nothing, and Claude's custom connectors work on every Claude plan, including the free tier, on the Claude phone app too. There is no login on our end and no API key. It is about as low-commitment as a tool gets.

Do I need to know what an MCP server is?

No. You copy one link, paste it into Claude's Connectors setting, and you are done. That is the whole thing. 'MCP' is just the plumbing underneath; you never have to think about it.

Why not just ask ChatGPT or Claude directly?

General AI models answer code questions from memory, and they get NEC ampacity, derating, and the small-conductor rules wrong often enough to fail an inspection. Intry does not guess: every answer comes from the same calculator our website runs, and every build re-derives those calculators' numbers from the locked source modules and re-runs the gate over them. The AI's reasoning plus Intry's real math is the combination you can actually stand behind on the job.

Does it work on my phone?

Yes. Claude's custom connectors work in the Claude mobile app, so you can add Intry once and then ask from your phone in the field. For saving your jobs and tracking a reading across visits, install the Intry app too (see the link on this page).

What about ChatGPT?

Claude is the easy path today because its connectors work on every plan and on the phone. ChatGPT can connect too, but it currently needs a paid plan with Developer Mode turned on, so it is not as smooth for most people yet. We lead with Claude; the ChatGPT path should get easier as its connectors open up. Developers using ChatGPT, Cursor, or Claude Code can connect now with the snippet lower on this page.

Using ChatGPT, Cursor, or a dev tool?

Intry is a standard MCP server (Streamable HTTP, JSON-RPC 2.0) at https://www.intrysys.com/api/mcp. The tool manifest is at /api/tools. ChatGPT (Plus, Developer Mode): Settings, Connectors, add a custom connector by that URL.

Claude Code (CLI)
claude mcp add --transport http intry https://www.intrysys.com/api/mcp
Cursor / Windsurf / VS Code / Claude Desktop config
{
  "mcpServers": {
    "intry": {
      "type": "http",
      "url": "https://www.intrysys.com/api/mcp"
    }
  }
}

Give your AI the code book.

One paste into Claude and every number your assistant gives you comes back computed and cited.

Add Intry to ClaudeBrowse the calculators