Equipment

Tight houses need ventilation on purpose. The 5 ACH50 code threshold, exhaust-only versus supply versus balanced systems, and how moisture decides between an HRV and an ERV.

Water dripping from the head, musty smells, weak airflow and blinking codes. What each usually means, what cleaning fixes, and the flare joint leak that often traces back…

What an annual boiler service should test for hot water and steam systems, the three safety devices that matter most, what oil boilers need, and the owner’s jobs…

Two visits a year, the checks only heat pumps need, what the owner should do about snow and ice, and the silent backup-heat fault a fall visit should…

Most AC repairs are six parts. A symptom-to-part map, the checks worth making before a service call, and the repairs that tend to tip the decision toward replacement.

The 1/300 and 1/150 ratios, what net free ventilating area means, a worked calculation, and why exhaust without intake pulls conditioned air out of the house.

Evaporative cooling works only where the air is dry, and needs windows partly open by design. DOE’s figures on temperature drop, energy use, sizing in cfm and maintenance.

Symptom by symptom, for electric, gas and tankless units. What an owner can safely check, why sediment slows recovery, and the two findings that mean replacement.

Leakage is measured with a duct blaster and reported as CFM25. What the numbers should be, when sealing is enough, when replacement is the answer, and why cleaning…