Most commercial buildings in Calgary are heated and cooled by rooftop units. When one breaks down, the question is usually not just “can it be fixed?” but “is it worth fixing again?” A repair that gets you through the winter can be the right call. So can a planned replacement before the unit fails on the coldest night of the year.
Here is how we help owners and property managers decide.
1. How old is the unit?
A well-maintained rooftop unit often lasts 15 to 20 years. Calgary is hard on them: deep cold, fast temperature swings, hail and long heating seasons. Once a unit is past 15 years, every major repair deserves a second look, because the next part to fail is often not far behind.
2. What has it cost you lately?
Add up what the unit has cost in repairs over the last two or three years. If a single repair is approaching half the cost of a new unit, or the unit needs a service call every few weeks in heating season, replacement usually comes out ahead. Repeated calls for the same problem, like short cycling or a unit that won't heat, are a sign the unit is wearing out, not just unlucky.
3. The heat exchanger
On gas-fired rooftop units, the heat exchanger is the part that keeps combustion gases separate from the air going into your building. A cracked or badly corroded heat exchanger is a safety issue, and on an older unit it is usually the point where replacement makes more sense than repair.
4. Compressor and refrigerant
A failed compressor on an older unit is one of the most expensive repairs there is. Older units may also use a refrigerant that is being phased out and getting more expensive. If the cooling side fails on a unit that is already near the end of its life, it is worth pricing a replacement before committing to the repair.
5. Is the unit still right for the space?
Spaces change. A unit sized for an office may struggle once the space becomes a restaurant or a gym. If a zone has always been too hot or too cold, a replacement is a chance to fix that properly instead of living with it. Our article on offices that are too hot or too cold covers some of the usual causes.
6. What a replacement involves
- Crane lift: most rooftop replacements need a crane to remove the old unit and set the new one, usually done early in the morning to keep disruption low.
- Curb fit: the new unit has to sit on the existing roof curb, or an adapter curb if the sizes don't match.
- Gas, power and controls: connections are checked and updated, and the thermostat is set up for your hours.
- Timing: where possible, plan replacements for spring or fall, not the middle of a cold snap.
7. When repair is still the right answer
Plenty of rooftop units are worth repairing: a failed igniter, flame sensor, inducer motor, belt or control board on a unit that is otherwise in good shape is a normal repair. The point is to make the decision with the whole picture, not one breakdown at a time. Regular maintenance visits also give you a written record of the unit's condition, so a replacement never comes as a surprise.
Get an honest answer
YYC Mechanical services and replaces rooftop units for restaurants, offices, retail and commercial buildings across Calgary and nearby towns, with 24/7 emergency service. Tell us the unit's age and what has been going wrong, and we will tell you whether a repair still makes sense.