Emergency HVAC FAQ

If you smell gas, do NOT turn on or off any electrical switches, phones, or devices. Leave the building immediately and take other occupants with you. Once you are safely outside, call 911 and then the gas utility (Con Edison: 1-800-752-6633 or National Grid: 1-718-643-4050). Do not re-enter the building until emergency responders confirm it is safe. After the area is cleared, call an HVAC technician to inspect your equipment.

Loud banging or rumbling from a boiler can indicate several issues, some potentially serious. Kettling (a rumbling sound) is caused by mineral buildup restricting water flow and causing localized boiling. Water hammer (sudden banging) in steam systems is typically caused by trapped condensate. While not always an immediate emergency, both conditions can damage the boiler over time and should be addressed promptly. If the sounds are accompanied by steam or water leaking, consider it urgent.

Consider it an emergency if: you smell gas or suspect a gas leak, you have no heat and outdoor temperatures are below freezing, you see water flooding from HVAC equipment, your carbon monoxide detector is alarming, you see sparks or smell burning from HVAC equipment, or you have no AC and a household member has a medical condition affected by heat. For non-emergency issues, you can schedule a regular service call during business hours, which is typically less expensive.

Carbon monoxide is odorless and colorless, making it extremely dangerous. Warning signs include CO detector alarms (the most reliable indicator), flu-like symptoms (headache, dizziness, nausea) that improve when you leave the building, soot or yellow/brown staining around HVAC equipment, a yellow or flickering pilot light or burner flame, and excessive moisture on windows near the equipment. If your CO detector alarms, evacuate immediately and call 911.

If you suspect frozen pipes in your HVAC system, do not try to thaw them with an open flame. Turn off the water supply to prevent flooding when the pipes thaw. Open faucets slightly to relieve pressure. Apply gentle heat using a hair dryer, heat lamp, or warm towels. Call a professional immediately, as frozen pipes can burst when they thaw, causing significant water damage. Prevent future freeze-ups by insulating exposed pipes.

Turn off the HVAC system immediately to stop additional water production. If the leak is near electrical components, turn off the relevant circuit breaker. Place towels and containers to catch the water. For boiler or heating system leaks, close the water supply valve. For AC leaks, the most common cause is a clogged condensate drain line. Take photos of the damage and call for professional repair. Do not ignore HVAC water leaks — they can cause significant property damage and mold growth.

A burning smell from your HVAC system should be taken seriously. A brief dusty or burning smell when first turning on your heating after summer is usually normal (dust burning off heat elements). However, a persistent burning smell, a smell of burning plastic or rubber, or visible smoke indicates a potentially dangerous condition such as an overheating motor, melting wiring, or a mechanical failure. Turn off the system and call for professional inspection before running it again.

Emergency and after-hours service calls do typically carry a premium compared to standard business-hours service. This covers the cost of maintaining 24/7 on-call technicians and the immediate-response logistics. However, we believe emergency service should be accessible, and our emergency rates are competitive within the NYC market. We provide upfront pricing before any work begins so there are no surprises, and we never charge for diagnostic time that does not lead to a repair.

The most effective way to prevent HVAC emergencies is through regular preventive maintenance — annual service for heating systems (in fall) and cooling systems (in spring). Other preventive measures include changing filters regularly, keeping outdoor units clear of debris, monitoring your system's performance for changes, not ignoring unusual sounds or smells, and ensuring your CO detectors have working batteries. Most HVAC emergencies we respond to could have been prevented with timely maintenance.

For no-heat emergencies: close curtains, use safe space heaters away from combustibles, and keep interior doors closed to retain heat. For no-AC emergencies: close blinds, use fans, stay hydrated, and go to a cooling center if necessary. For gas leaks: stay outside until cleared by authorities. For water leaks: contain the water with towels and buckets, turn off the system, and move valuables away from the water. Document any damage with photos for insurance purposes.