Privacy policy.

Who we are

BTU Size (btusize.com) is a free HVAC resource for homeowners, with calculators, cost guides, brand comparisons, and troubleshooting pages. We are the data controller for everything described in this policy.

For any privacy question or data request, including to see what we hold, correct it, delete it, or opt out of processing, use the contact page and pick "Data, privacy, or account request" from the subject dropdown. We respond within 30 days, per GDPR and CCPA timelines.

What we collect when you browse

Reading a guide, comparing two systems, or running a calculator does not require an account and does not ask for your name or contact details. The calculators are client-side JavaScript, so when you type a square footage, climate zone, target superheat, or any other value, the math runs in your browser and the result renders on the page. None of those values reach a btusize.com server, because the math does not need one. Close the tab and the inputs are gone; nothing you type is stored on our end or tied to your identity.

What we do collect across the whole site is anonymized traffic analytics, and the pages you see may serve ads. Both rely on cookies and are described below. The only time you hand over personal details is if you choose to fill in a contractor quote form, which is also covered below.

Google Analytics 4 (cookies and traffic measurement)

We use Google Analytics 4 (GA4) to understand how the site is used: which pages get visited, where visitors come from, what device they are on, and how long sessions last. GA4 is operated by Google LLC in the United States and Google Ireland Limited in the European Union.

What GA4 collects when you visit btusize.com:

• A truncated (anonymized) version of your IP address. The last octet is dropped before storage so the IP cannot be tied back to a single household.
• Pages you viewed and the order you viewed them in
• How long you spent on each page
• Your browser, operating system, screen size, and language
• The referrer URL that sent you to the site (Google search, social media, direct, etc.)
• An anonymous client ID stored in a first-party cookie so we can recognize a returning visitor as the same visitor across pageviews

GA4 does not collect your name, email address, exact location, or any input you type into a calculator. We have disabled the Google Signals feature, so GA4 does not link your activity to your Google account if you happen to be logged in.

You can opt out of GA4 entirely by installing the official Google Analytics opt-out browser add-on, by using a tracker-blocking extension like uBlock Origin, or by enabling "Do Not Track" or "Global Privacy Control" in your browser. We honor GPC signals.

For the full picture of how Google handles GA4 data, see the Google Privacy Policy.

Third-party advertising

Pages on btusize.com may display advertising served by third-party ad networks. Ad networks place cookies on your device and use them to measure ad performance and tailor the ads you see based on your activity across this site and other sites in their network. This practice is known as personalized or interest-based advertising.

The data an ad network may collect includes a cookie identifier, your IP address, the page you are on, the time of your visit, and information about your browser and device. Each network has its own data-handling policy, which you can read by clicking the AdChoices icon usually shown on individual ads. We do not control how a third-party ad network processes this data once it receives it.

To opt out of personalized advertising from most major networks in one place, use the Digital Advertising Alliance's consumer opt-out tool (US), Your Online Choices (EU/UK), or the AdChoices opt-out tool (Canada). Browser extensions like uBlock Origin block ad scripts entirely.

For European Union and UK visitors, ads will respect the consent signal sent through the IAB Transparency and Consent Framework or the relevant ad network's consent tooling. Until consent is given, only non-personalized ads will be shown.

Contractor quote requests

Certain pages on the site include optional forms that let homeowners request a quote or a callback from a local HVAC contractor. These forms are never a required step to use anything on the site. Filling one out is your choice.

When you submit a form, we collect the minimum needed to make the contractor introduction: name, email address, phone number, ZIP code, project type, and any notes you add. That information is passed to contractor partners who are licensed in your jurisdiction and have agreed to our data-handling terms.

Your submission is retained for 24 months so we can handle warranty disputes or quote-follow-up requests, then deleted. To revoke consent, remove your information sooner, or stop further contact from a contractor we introduced you to, use the contact page as described under "Who we are."

Children under 13

This site is built for homeowners and HVAC tradespeople. We do not knowingly collect information from children under 13. If you believe a child has provided information to us, let us know via the contact page and we will delete it.

Your rights (GDPR, UK GDPR, and CCPA)

If you are in the European Union, the United Kingdom, or California, you have additional rights over how we process your personal information. These include:

• Right of access. Ask us what personal data we hold about you.
• Right to deletion. Ask us to delete the personal data we hold about you (and, where applicable, ask us to instruct our processors to do the same).
• Right to correction. Ask us to fix inaccurate information.
• Right to opt out of sale or sharing. Personal information is not sold for monetary consideration or shared with third parties for cross-context behavioral advertising. California residents can request written confirmation by email.
• Right to non-discrimination. Exercising any of these rights does not change site access or pricing.
• Right to lodge a complaint. EU and UK residents can file a complaint with their national data protection authority if they believe we have mishandled their data.

To exercise any of these rights, use the contact page as described under "Who we are," and include a way to confirm your identity so we do not act on the wrong person's data.

Links to other websites

Pages across the site cite outside organizations like ACCA, ASHRAE, NFPA, EIA, DOE, and ICC. When you click one of those links, you leave btusize.com and land on that organization's site. Their privacy policy governs what they collect, not ours. We have no control over their cookies, analytics, or data handling.

Changes to this policy

We may update this policy from time to time. The "Last updated" date at the top of the page changes when we do. Material changes (new data collected, new sharing arrangements, new analytics tools) will be flagged with a banner on the homepage for at least 30 days so returning visitors notice.