HVAC Resources & Building-Science Guides

Straight answers about sizing, humidity, rebates, freezes, and how HVAC really works

Guides From a Building-Science HVAC Company


Most HVAC advice online is either a sales pitch or a rule of thumb. Texcellent A/C Service takes a different approach: we size systems with a Manual J load calculation, verify the building envelope with a blower door, and measure airflow before we recommend anything. That is what "test, don't guess" means. These guides explain the building science behind comfort, humidity, and efficiency for homes across Deer Park and Greater Houston, so you can make an informed decision. Questions? Call 281-402-5100.

What Size AC Do I Need? A Manual J Load Calculation Guide

Square-footage rules of thumb get AC sizing wrong. This guide walks through how a Manual J load calculation actually sizes a system - step by step - and why right-sizing matters more in Houston than almost anywhere else.

Read the Manual J guide

Why Is My House So Humid in Houston - and How to Fix It

Sticky air, musty smells, and window condensation are not just "Houston weather." This guide explains what actually drives indoor humidity - from oversized AC to a leaky envelope - and the real fixes, including whole-home dehumidifiers.

Read the humidity guide

AC and Heat Pump Rebates in Houston, Town by Town

The rebate comes from the wires company on your bill, not the electricity provider you picked. Which of CenterPoint, TNMP and Entergy Texas serves your town, how each one pays, and the current status of the federal credit and the Texas HOMES and HEAR programs. Verified and dated.

Read the rebates guide

Will a Heat Pump Keep Your Houston Home Warm in a Freeze?

Yes, below 32 degrees too. What a heat pump does at 19 degrees, when auxiliary heat runs and when emergency heat should not, why older Ship Channel homes lose heat through attic ducts, and a checklist to run before the first freeze.

Read the freeze guide

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