Heating & Cooling
Rooftop Unit Repair
No heat, no cooling, short cycling, or a unit that trips off every cold morning: diagnosed and repaired on the roof, with maintenance that keeps it from happening again.
Heating & Cooling
No heat, no cooling, short cycling, or a unit that trips off every cold morning: diagnosed and repaired on the roof, with maintenance that keeps it from happening again.
A packaged rooftop unit is a furnace and an air conditioner bolted together in one cabinet that lives outdoors. The parts list is familiar, and so are the failures. The difference is that every one of them happens on a roof, in weather, on equipment that a business depends on during open hours.
Most of these are a same-day fix when the diagnosis is right. Guessing at parts on a roof is expensive, so we do not.
| Symptom | Most common cause | Typical fix |
|---|---|---|
| Blower runs, no heat | Igniter, flame sensor or gas valve | Clean or replace, usually the same visit |
| Trips off on cold mornings, fine later | Loaded filters, slipping belt or low gas pressure | Airflow correction and a pressure check under load |
| Squeal on startup | Worn or loose belt | Belt and tension, plus a bearing check |
| Ice on the coil in summer | Refrigerant leak or restricted airflow | Leak search, charge and airflow correction |
| Cold air from the ducts in January | Economizer damper stuck open | Actuator or outdoor air sensor |
| Unit dead, no fan at all | Transformer, disconnect or tripped breaker | Electrical repair on the same visit |
Rooftop units fail in ways a basement furnace never will. Standing water rots the base rail. Wind-driven snow packs the economizer hood and the flue. Hail folds condenser fins flat. Grease from a kitchen exhaust fan coats the coil of the unit downwind of it and cuts its capacity in half by midsummer. Birds and rodents nest in cabinets over the winter and chew low-voltage wiring.
Access shapes the repair too. A unit sitting more than a few feet from a roof edge, or on a roof with no hatch, changes how our technicians get up and what they can carry. We note the access on every account so the next visit does not start with a trip back to the truck for a taller ladder.
The technician gets on the roof, pulls the panels, and works the problem from the symptom back to the cause: gas pressure, temperature rise, amp draw, static pressure and refrigerant readings, not just the part that looks tired. You get the findings in plain language, with photos from the roof, and a written price before any repair starts. If a part has to be ordered, we tell you the lead time and whether the unit is safe to run in the meantime.
We work on every major brand: Carrier, Trane, Lennox, York, Rheem, Daikin, Goodman, Heil, Armstrong and Aaon are all in our service records. If the unit was installed by another company, that does not matter. If the failure is on a unit we installed, our Lifetime Workmanship Guarantee covers the labor.
Some repairs are not worth making, and we say so. A cracked heat exchanger is a safety issue that ends the conversation about repairing the gas section. A failed compressor on a fifteen-year-old unit that runs on R-410A means paying a premium for a refrigerant that is no longer manufactured, on equipment that will be back on the list next year. Repeated board and motor failures on the same unit usually mean the unit is done rather than unlucky.
When that is the situation, we show you the repair number and the replacement number together and explain which one we would pick. Our rooftop unit replacement page covers what a changeout involves, including crane day and curb adapters, so you can see the whole picture before deciding.
Nearly every rooftop emergency we see has a maintenance history behind it. Filters that went two seasons. A belt nobody looked at. A condenser coil that has not been cleaned since the unit was set. Spring and fall visits catch those before they become a no-heat call on the coldest Monday of the year.
A proper visit covers filters and belts, coil cleaning, a combustion check on the gas section, a heat exchanger inspection, economizer operation, refrigerant charge, electrical connections and drain pans. For buildings with several units we keep an equipment list with model, serial, filter sizes and belt numbers, so the truck arrives stocked. Our commercial maintenance agreements are set up per unit and include priority scheduling when something does fail. General HVAC maintenance for the rest of your building, along with duct cleaning and indoor air quality work, runs through the same team.
We have serviced rooftop units across New Hampshire, New Jersey and southern Maine for years, with more than 260 packaged and rooftop units in our records, and our technicians are on commercial roofs every spring and fall. We know which failures this climate produces and which ones a coastal site produces on top of that.
One licensed team covers the whole unit: the HVAC, the gas piping and the electrical, so a repair that turns out to be a tripped breaker or a failed disconnect is handled on the same visit. Every repair carries our Lifetime Workmanship Guarantee. High Ground is veteran-owned, the mission is giving the trades a good home, and a real person answers the phone when the unit goes down. For everything else we do for businesses, see commercial HVAC.
When you invite us into your home, we take that responsibility seriously. Every project - big or small, is handled with care, respect, and craftsmanship you can feel. Our Lifetime Workmanship Guarantee means every job is done right — or we make it right, fast.
Every technician undergoes rigorous training and continuous skill upgrades.
“They always kept me updated with the schedule. Made a rather complex job run like clockwork.”
- Dave, NH
“Super quick & professional. Looking forward to working with them in the future. Highly recommend!”
- Enrique, NJ
“Went out of his way to help us with our new house that we’d just purchased with helpful tips.”
- Eric, NH
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Why does my rooftop unit run but not heat the building?
The blower is running, so the unit has power and a call for heat, but the gas section is not lighting or staying lit. Common causes are a failed igniter or dirty flame sensor, a stuck gas valve, an inducer motor that is not proving draft, or a rollout or high-limit switch that has opened and locked the unit out. A unit that lights and then shuts down a few minutes later usually points to airflow, most often loaded filters or a slipping belt tripping the high limit. The diagnosis takes one visit, and the fix is often the same visit.
Why does the unit trip off on cold mornings and work fine later?
Do I need to provide roof access?
How often should commercial rooftop units be serviced?
Can you service units that another company installed?
The rooftop unit is loud or vibrating. Is that urgent?
Tell us what you need - we’ll confirm your appointment and get your home back to comfortable, fast.
HOW QUICKLY CAN WE SERVE YOU?
Tell us how to reach you and a real person will call you back about rooftop unit repair.
Need someone now? Call (603) 262-3644
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