Can My HVAC System Cause Mould Growth in My Home?
CANRO Heating & Cooling provides expert advice on this common question for homeowners in Greater Vancouver. If you need professional service, our licensed technicians are available across the region.
Related Services from CANRO
CANRO Heating & Cooling provides comprehensive boiler service across Greater Vancouver, including diagnostic inspections, emergency repairs, scheduled maintenance, and system replacement. Our Red Seal certified technicians service all major brands and carry OEM parts in their vehicles. For emergency service related to this question, call (604) 359-1081.
Answer: Can My HVAC System Cause Mould Growth in My Home?
Yes — HVAC systems can contribute to mould growth if conditions are right. The most common causes are: condensate drain lines that are clogged, allowing water to back up and overflow into the air handler or furnace; evaporator coils that are dirty or have poor drainage, creating a moist environment for mould; ductwork that is poorly insulated, causing condensation on the duct surface in crawlspaces; and HRV/ERV units with dirty cores or blocked drains that harbour mould. Signs of HVAC-related mould include musty odours from supply vents, visible mould growth near vents or on the indoor unit, and worsening allergy symptoms when the system runs. Professional cleaning of the drain pan, evaporator coil, and ductwork may be needed to eliminate the mould source.
When to Call a Professional for Help
While understanding the answer to this question is helpful, some situations require professional expertise. If you are uncertain about any step, if the problem recurs, or if you notice any signs of gas odour, carbon monoxide, or electrical hazards, contact CANRO Heating & Cooling immediately. Our licensed technicians across Greater Vancouver can provide expert diagnosis and repair. We recommend professional service for any issue that involves gas, electrical components, or safety-critical systems.
Safety Reminder
If you smell gas, suspect carbon monoxide or believe there is an immediate danger, leave the property and contact emergency services or the appropriate gas emergency authority. Do not remain inside — exit the building immediately and call for help from outside.