Commercial HVAC Services in Chatham-Kent, Ontario

Postma has installed, maintained and repaired commercial HVAC equipment across Chatham-Kent since 1989 — rooftop units, boilers, make-up air, ventilation and refrigeration. Call 519-354-9491 for service, to discuss a preventative maintenance agreement for your building, or to request a quote on a larger new construction project.

Commercial HVAC Services We Provide

Postma has installed, maintained and repaired commercial HVAC equipment in Chatham-Kent since 1989. Rooftop units, boilers, make-up air and refrigeration — whether you are tendering a new build, putting a portfolio under contract, or standing in a mechanical room at 2am, the same company handles it.

New Construction & Design-Build

Load calculations, equipment selection, shop drawings and full mechanical packages for new commercial builds and tenant fit-outs.

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Preventative Maintenance

Scheduled seasonal service, written condition reports per unit, asset tagging and multi-year capital replacement forecasting.

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Repair & Emergency Service

24/7 diagnosis and repair on rooftop units, boilers, refrigeration and controls, with root-cause reporting after the call.

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Replacement & Installation

Like-for-like changeouts, curb adapters, crane work and system upgrades scheduled around your operating hours.

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Full Life Cycle Management for Commercial Buildings

Most buildings end up with one contractor who installed the equipment, a second who maintains it, and a third who eventually replaces it — each arriving without the history the last one had. Postma covers all four stages, so the equipment record never resets.

Stage 01

New Construction

Load calculations, equipment selection, installation and commissioning. The system is specified for how it will actually be serviced, not just for what passes inspection.

Design-build →

Stage 02

Ongoing Maintenance

Scheduled seasonal service, written condition reports and asset tagging. Keeps the manufacturer warranty valid and builds the service history the later stages depend on.

Maintenance plans →

Stage 03

Repair & Warranty

Emergency response, root-cause diagnosis and warranty work. We already know the unit, its age and what was flagged at the last inspection before we arrive.

Repair service →

Stage 04

Replacement & Upgrades

Planned changeouts forecast years ahead from condition data, scheduled around your operating hours — then the cycle starts again on the new equipment.

Replacement →

Dedicated teams at every stage. Postma runs separate maintenance, service and installation teams — 25+ service technicians and 40+ installers across HVAC, plumbing and electrical — rather than pulling the same crew off a construction site to answer a no-heat call. Many of our commercial clients have been with us from initial construction through maintenance, repair and eventual replacement of the same equipment.


Commercial HVAC Equipment We Service

Select a system type to see what we handle.

Rooftop Units (RTUs)
Packaged gas/electric and heat pump RTUs, single-zone and multi-zone, economizers, curb adapters and crane changeouts. The most common commercial unit in our service area and the one we stock parts for most heavily.
Boilers & Hydronic Systems
Condensing and atmospheric boilers, circulating pumps, glycol loops, expansion tanks, air separators, radiant and in-floor distribution, combustion analysis and annual certification.
Make-Up Air & Ventilation
Make-up air units, heat and energy recovery ventilators, kitchen exhaust hoods, washroom and process exhaust, and air balancing so the building is not fighting itself.
Commercial Refrigeration
Walk-in coolers and freezers, reach-in cases, condensing units and rack systems, defrost controls, leak detection and refrigerant compliance for food retail and processing.
Chillers & Split Systems
Air-cooled chillers, process chilled water, VRF and VRV systems, ducted and ductless splits, and dedicated cooling for server rooms and electrical rooms.
Unit & Infrared Heaters
Suspended unit heaters, tube and infrared radiant heating, garage and shop heaters, high-bay destratification fans, and heating layouts for warehouse and shop space.
Controls & Building Automation
Commercial thermostats, zone controls, sensors and actuators, scheduling and setback programming, and integration or troubleshooting on existing building automation systems.
Ductwork & Air Distribution
Sheet metal fabrication and installation, duct modifications for renovations and fit-outs, diffuser and grille layout, static pressure diagnosis and air balancing.

We service equipment we did not install. Most of our commercial maintenance customers came to us with existing equipment from another contractor. Bring us the building as it stands and we will document what is there.


Repair or Replace? How We Assess Commercial Equipment

The most expensive commercial HVAC decision is repairing a unit three times before replacing it anyway. We give you the numbers rather than a recommendation you cannot check.

What We Look At Why It Decides the Answer
Age vs expected life Commercial rooftop units typically last 12 to 20 years in the Ontario climate. A repair on a 19-year-old unit normally buys you a season, not a decade, which is why the cost / benefit analysis of repair vs. replacement becomes increasingly important as the system gets old. A 5-year old system that needs a repair often makes sense to repair, rather than replace.
Repair cost vs replacement We quote both so you can better understand the tradeoff between approving repairs versus a replacement unit. Our team also provides additional details like added efficiency and performance levels, if you have an older system.
Repair history on the asset Three service calls in two years is a replacement signal even when each individual repair looked reasonable at the time.
Refrigerant type Older units on phased-down refrigerants get more expensive to charge every year. This is an important factor when deciding on repair vs. replacement. For old units that are using R-22 (an old refrigerant type) and have a leak can become very expensive to charge given the price of R-22.
Parts availability Some parts can be very hard to source, particularly for older units, if the manufacturer no longer makes them and instead we need to procure the part from a distributor (assuming they stil have some in stock). Parts availability, and lead times, which can extend to up to a month to receive a part for older units, can impact the repair / replace decision based on how mission-critical the unit is to get working immediately.
Downtime cost to you A restaurant, a data room and a warehouse tolerate very different amounts of risk. We ask before recommending.

Emergency Commercial HVAC Repair

Postma has 80+ licensed technicians across 60+ stocked service vehicles dispatched from our Charing Cross Road shop in Chatham, with same-day response for buildings under a preventative maintenance agreement. Morning or night, weekday or weekend, our team is available for emergency commercial HVAC repairs.

  • 24/7 emergency commercial HVAC service
  • Stocked trucks carrying common RTU, boiler, refrigeration and control components
  • Temporary heating and cooling where a permanent repair will take time
  • Priority dispatch and no overtime premium for maintenance agreement customers
  • Root-cause reporting after the call, not just a restored unit

Emergency line: 519-354-9491


Commercial HVAC Services Beyond Chatham-Kent

Chatham-Kent is our core market, since we are based in Chatham, but our commercial division works across Southwestern Ontario. Each market has a different building stock and a different equipment mix.

Commercial HVAC in Sarnia & Lambton County

We cover all types of commercial, industrial, and multi-family buildings across Sarnia, Point Edward, Corunna and Petrolia.

Sarnia commercial HVAC →

Commercial HVAC in Windsor-Essex

From Leamington and Kingsville to Essex, Windsor and Amherstburg we have you covered for commercial HVAC repairs, new construction and replacement / installation in Windsor-Essex.

Windsor-Essex commercial HVAC →


Commercial HVAC FAQ

How long does a commercial rooftop unit last?

Typically 15 to 20 years in Southwestern Ontario, depending on run hours and whether it has been maintained. Units on a documented preventative maintenance program reliably reach the top of that range; neglected units often fail well short of it.

Do you service equipment you did not install?

Yes, and most of our commercial maintenance customers came to us that way. We inspect and document what is already on the building, tag the assets, and build the service history from there.

How often should commercial HVAC equipment be serviced?

Twice a year minimum — once before heating season and once before cooling season. High run-time equipment such as refrigeration, kitchen make-up air and process cooling typically needs quarterly service.

Do you handle commercial refrigeration as well as HVAC?

Yes. Walk-in coolers and freezers, reach-in cases, condensing units and rack systems, including defrost controls and refrigerant compliance for food retail and food processing facilities.

Can you provide load calculations and equipment selection for a new building?

Yes. We take design-build and design-assist mechanical scope, which includes load calculations, equipment selection, shop drawings, commissioning and owner training. See commercial HVAC new construction.

Will you replace a rooftop unit outside of business hours?

Yes. Changeouts on retail, restaurant and occupied office buildings are routinely scheduled overnight or on weekends. Crane work and roof access get coordinated in advance so the building is running before you open.

Do you offer maintenance agreements for multiple buildings?

Yes. We currently maintain 300+ commercial sites under agreement, including multi-building portfolios consolidated into a single contract, renewal date and asset register.

Need commercial HVAC service or a quote? Call 519-354-9491 or request a commercial assessment. We also provide commercial plumbing and commercial electrical services, or see all commercial services.

Need commercial HVAC service or a quote? Call 519-354-9491 or request a commercial assessment. We also provide commercial plumbing and commercial electrical services, or see all our commercial services.