Frequently Asked Questions
Find answers to the most common questions about our combustion, boiler, HVAC, ventilation and mechanical plumbing services.
What is the difference between a hot water boiler and a steam boiler?
A hot water boiler heats water below the boiling point to feed a network of radiators or radiant floor systems. A steam boiler produces pressurized steam, used for heating or industrial processes. Maintenance and safety requirements differ significantly.
Source: Hot Water and Steam Boilers
What are the signs that a boiler needs repair?
Decreased efficiency, rising gas consumption, unusual noises, water leaks, unstable or yellow flame, recurring error codes, and difficulty maintaining the set temperature are common indicators.
Source: Hot Water and Steam Boilers
How long does a commercial boiler last?
A well-maintained commercial boiler has a typical lifespan of 20 to 30 years. A regular preventive maintenance program and proper water treatment are the key factors in longevity.
Source: Hot Water and Steam Boilers
What types of air conditioning systems do you service?
Rooftop units (RTUs), air-cooled and water-cooled chillers, commercial heat pumps, VRV/VRF systems, air handling units (AHUs), and commercial split systems.
Source: Commercial and Industrial Air Conditioning
How often should a commercial rooftop unit be serviced?
Semi-annual maintenance is recommended: one visit before the heating season and one before the cooling season. High-use environments may require quarterly visits.
Source: Commercial and Industrial Air Conditioning
Do you handle refrigerant recharges?
Yes. Our technicians perform refrigerant recharges in compliance with current regulations. We also verify circuit integrity before any recharge to prevent recurring leaks.
Source: Commercial and Industrial Air Conditioning
What types of emergencies do you cover?
Boiler failures, burner shutdowns, gas leaks detected by safety systems, winter heating breakdowns, air conditioning failures during heat waves, critical pump failures, and any mechanical breakdown that threatens occupant comfort or safety.
Source: 24/7 Emergency Repair
What is your emergency response time?
We dispatch a technician as soon as a call is received. Response time varies based on location and availability, but our goal is to respond as quickly as possible across Grand Montréal.
Source: 24/7 Emergency Repair
How do I reach the emergency service?
Call 450-473-0909. The line is available 24/7, including weekends and holidays.
Source: 24/7 Emergency Repair
What is energy optimization for a commercial building?
Energy optimization involves analyzing how mechanical equipment operates and adjusting its settings to reduce energy consumption without compromising comfort or production. This includes combustion tuning, scheduling optimization, and retrofitting obsolete equipment.
Source: Energy Optimization
What kind of savings can be expected?
Results vary depending on the initial condition of the equipment and the type of intervention. An energy audit identifies concrete opportunities and quantifies potential savings before any work begins.
Source: Energy Optimization
Are there subsidies available for energy optimization?
Yes. Several government programs, such as ÉcoPerformance from Transition énergétique Québec, offer financial incentives for energy efficiency projects in commercial and institutional buildings. Montréal Combustion can guide you to the applicable programs.
Source: Energy Optimization
What types of gas burners do you service?
We service atmospheric, premix, modulating, and high-efficiency burners from manufacturers such as Power Flame, Riello, Dungs, and many others.
Source: Natural Gas Combustion and Heating
How often should a natural gas burner be inspected?
A minimum of one annual inspection is recommended. High-usage systems or those in critical environments benefit from semi-annual maintenance with combustion analysis.
Source: Natural Gas Combustion and Heating
Do you offer emergency service for gas heating breakdowns?
Yes. Our 24/7 emergency service covers combustion breakdowns throughout Grand Montréal, including Rive-Nord and Rive-Sud.
Source: Natural Gas Combustion and Heating
What is the difference between residential plumbing and mechanical plumbing?
Mechanical plumbing deals with large-scale systems in commercial and industrial buildings: circulation pumps, pressurized hot water networks, commercial water heaters, water treatment systems, and control valves. The technical and regulatory requirements are significantly different from residential plumbing.
Source: Mechanical Plumbing
What types of pumps do you service?
Circulation pumps for heating networks, booster pumps, condensate pumps, and process pumps. We service brands such as Grundfos, Bell & Gossett, and many others.
Source: Mechanical Plumbing
Do you offer water treatment services for boilers?
Yes. Water treatment is essential to prevent corrosion, scale buildup, and contamination in boilers and hot water networks. We offer water analysis, treatment system installation, and ongoing monitoring programs.
Source: Mechanical Plumbing
What types of equipment are covered?
Hot water and steam boilers, gas burners, rooftops, air conditioning systems, ventilation, pumps, valves, and commercial water heaters.
Source: Preventive Maintenance — Boilers, HVAC, and Mechanical Equipment
What is the recommended maintenance frequency?
Frequency depends on equipment type and usage intensity. An annual minimum is recommended, with semi-annual visits for critical systems.
Source: Preventive Maintenance — Boilers, HVAC, and Mechanical Equipment
Why is ventilation important in a commercial building?
Ventilation ensures indoor air renewal, removes pollutants, controls humidity, and maintains a healthy environment for occupants. Inadequate ventilation can lead to health issues, mold growth, and regulatory compliance problems.
Source: Ventilation and Indoor Air Quality
What types of ventilation systems do you service?
Exhaust fans, air exchangers, air handling units (AHUs), heat recovery ventilators (HRVs), and energy recovery ventilators (ERVs).
Source: Ventilation and Indoor Air Quality
How can you tell if a building's ventilation is inadequate?
Excessive window condensation, persistent odors, occupant complaints about air quality, high CO2 levels, and mold growth are common indicators of insufficient ventilation.
Source: Ventilation and Indoor Air Quality
Does ÉcoPerformance always cover the same types of equipment?
Eligible categories and calculation rules can change from one period to the next. Consult the current documentation when structuring your project and confirm with a program advisor or the official portal.
Source: Energy Efficiency Subsidies and Programs in Québec
Is an audit required before replacing a boiler?
Programs often require a demonstrated need, baseline measurements or a savings tracking method. A technical audit or characterization strengthens the application, even when the replacement seems obvious on paper.
Source: Energy Efficiency Subsidies and Programs in Québec
Who coordinates the technical and administrative sides?
Best practice separates energy assumptions, before/after measurements and responsibilities among equipment suppliers, contractors and building owners. Montréal Combustion can support the implementation and mechanical optimization side.
Source: Energy Efficiency Subsidies and Programs in Québec
How often should a commercial boiler be inspected?
A full preventive maintenance inspection is recommended at least once a year. Critical or high-usage systems benefit from semi-annual inspections.
Source: Preventive Boiler Maintenance: Reducing Breakdowns and Costs
What are the signs that a boiler needs maintenance?
Decreased efficiency, unusual noises, an unstable flame, leaks or rising gas consumption are common indicators.
Source: Preventive Boiler Maintenance: Reducing Breakdowns and Costs
Does a lower efficiency rating alone justify replacement?
Efficiency is one factor, but it must be weighed against operating hours, the relative cost of thermal losses elsewhere in the building and the condition of the heat exchanger. An integrated assessment avoids replacing for a marginal gain when other losses dominate.
Source: When Should You Replace a Commercial Boiler?
Can maintenance alone extend useful life indefinitely?
Rigorous maintenance often extends service life, but it doesn't eliminate heat exchanger wear or control obsolescence. Beyond a certain threshold, unplanned shutdowns cost more than planning a replacement.
Source: When Should You Replace a Commercial Boiler?
Does an upgrade always qualify for incentive programs?
Certain projects may be eligible for efficiency programs when current criteria are met. Eligibility must be confirmed at project time through official sources — never assume specific amounts.
Source: When Should You Replace a Commercial Boiler?
Is hard water alone enough to explain a drop in efficiency?
Hardness promotes scaling on heat exchange surfaces, but conductivity, alkalinity and dissolved oxygen also contribute to deposits and corrosion. A full water profile is needed, not just a single parameter.
Source: Water Treatment and Boiler Performance
What's the role of a pressurization unit or blowdown tank in some circuits?
These devices maintain system pressure and reduce air ingress, which limits certain corrosion mechanisms and stabilizes operation. Their adjustment and maintenance are part of the overall hydraulic ecosystem.
Source: Water Treatment and Boiler Performance
Who should adjust treatment chemicals?
Chemical products must be handled and dosed according to safe protocols and applicable regulations. Coordination between the water treatment supplier and the mechanical team ensures consistent objectives.
Source: Water Treatment and Boiler Performance
How often should RTU filters be replaced?
Frequency depends on dust load and the surrounding environment (roads, kitchens). In commercial settings, quarterly replacement is often a minimum; pressure-drop readings help fine-tune the schedule.
Source: Rooftop Units: Maintenance and Troubleshooting
The belts are squealing — is it urgent?
A worn or loose belt reduces airflow, increases energy consumption and can damage pulleys. Correct the tension or replace based on observed wear before failure during a peak period.
Source: Rooftop Units: Maintenance and Troubleshooting
How do I schedule a visit on the Rive-Sud or Rive-Nord?
Specify roof access details, building occupancy hours and alarm history. You can reach Montréal Combustion at 450-473-0909 to coordinate maintenance or troubleshooting.
Source: Rooftop Units: Maintenance and Troubleshooting
Why does the unit start then shut down immediately?
Causes range from pressure switch trips to partial icing, sensor faults or motor protection. Record the code, measure against the manufacturer's specified ranges and avoid repeated resets without identifying the root cause.
Source: Commercial Air Conditioning Breakdown: Rapid Diagnosis
The building is overheating — should I open fire doors for ventilation?
Never compromise compartment separation or smoke control systems. Use existing mechanical ventilation, inform occupants and call a team to restore cooling or activate the designed backup ventilation.
Source: Commercial Air Conditioning Breakdown: Rapid Diagnosis
How can I speed up the on-site intervention?
Provide the model, approximate age, last maintenance dates, filter replacement history and any unusual noise or smell. For urgent requests, call 450-473-0909 to coordinate a commercially-focused response.
Source: Commercial Air Conditioning Breakdown: Rapid Diagnosis
When should you call emergency services instead of an HVAC technician?
If there is a persistent gas odor, unexplained discomfort, a carbon monoxide alarm or any situation you consider dangerous, use the appropriate emergency line first. Technical troubleshooting comes after occupant safety is secured.
Source: Natural Gas Burner Emergency: What to Do When It Fails
Can I reset the burner myself after a lockout?
Repeated resets often mask an underlying fault. Without a proper diagnosis, you risk fouling, improper combustion settings or a safety device failure. Have a qualified technician handle the intervention.
Source: Natural Gas Burner Emergency: What to Do When It Fails
How do I reach a team for an emergency on the Rive-Nord or Rive-Sud?
For service requests or emergencies related to combustion and commercial HVAC systems, call 450-473-0909. Specify the equipment type, symptoms and any error codes displayed.
Source: Natural Gas Burner Emergency: What to Do When It Fails
How do you know if a building is under-ventilated?
Indicators like excessive humidity, persistent odors or pressure differences between zones can raise flags, but a proper diagnosis relies on airflow, CO₂ or pressure measurements depending on the context and site objectives.
Source: Ventilation and Indoor Air Quality in Commercial Buildings
Does higher MERV filtration solve everything?
Finer filtration reduces certain particles but typically increases pressure drop: you need to verify that fans and ductwork can sustain the required airflow without degrading energy performance or creating under-ventilation.
Source: Ventilation and Indoor Air Quality in Commercial Buildings
What's the link between HRV and operating costs?
Heat recovery units and modulation strategies reduce energy losses when sensors and valves are properly calibrated. Neglected maintenance cancels out a portion of the expected savings.
Source: Ventilation and Indoor Air Quality in Commercial Buildings
24/7 Emergency — Fast Response Across Grand Montréal
Boiler failure, equipment breakdown or heating emergency? Our technicians respond quickly.
450-473-0909