Two kinds of calls come in. The first is the system that has stopped entirely: no cool air on a July afternoon, no heat when the temperature drops overnight. The second is the system that is running but not doing its job: the house never quite reaches the temperature on the thermostat, one room is always warmer than the rest, or the equipment cycles on and off without settling into a rhythm. Magnum Heating & A/C handles both. Terrell Hills homeowners and property managers call us for the full range of heating and cooling work, from a same-day repair to a complete system replacement.
The homes here tend to be older and well-kept, and older equipment carries its own patterns: ductwork that was never properly sized for additions, thermostats that have been in place for years, and systems that have been repaired more than once without anyone stepping back to look at the whole picture. We take the straightforward calls and the complicated ones. Call (830) 590-9782 for a quote and we will confirm pricing before anything is scheduled.
Pricing for HVAC work is not a fixed number until someone has looked at the system. What moves a quote is what the fault turns out to be, what has to be reached to get at it, and whether a repair is the right answer or whether the equipment has reached the point where replacement makes more sense.
A diagnostic call for a system that will not start is priced differently from a full system replacement, and a ductwork repair that requires access to a finished ceiling is a different job from one that runs through an open attic. We explain what the job involves and what it will cost before any work begins. You get the rate on the phone, and the price is confirmed before we schedule.
We do not offer a free estimate or a free inspection. What you get is a clear answer about what the work covers and what it will cost, so you can make a decision before anyone arrives. If the scope changes once the technician is on site, that conversation happens before any additional work is done.
When the system does not respond at all, the cause is usually electrical or mechanical rather than a refrigerant issue. We check the capacitor, the contactor, and the control board before assuming the worst. A failed capacitor is one of the more common reasons a condenser stops starting, and it is a repair that does not require replacing the whole unit. We test each component and tell you what we find.
A furnace that fires and then shuts off, or that will not light at all, is often a flame sensor problem. The sensor gets coated over time and loses the ability to confirm that the burner is lit, so the control board shuts the system down as a safety measure. Cleaning or replacing the sensor resolves it in most cases. Ignition faults follow a similar pattern and are worth diagnosing before assuming the heat exchanger or the gas valve is at fault.
These three components sit at the center of how a system starts, runs, and shuts down. A contactor that has pitted or burned through will prevent the compressor from engaging. A failing control board can produce symptoms that look like several different problems at once, which is why a proper diagnostic matters before parts are ordered. We test the controls, identify the failed component, and replace what needs replacing.
A furnace that runs but blows cold air, a system that short-cycles without warming the space, or a unit that does not come on at all each point to different causes. We work through the sequence: thermostat signal, ignition, flame sensor, heat exchanger, and blower. We treat your home and its system the way we would our own, which means we look at the full picture rather than stopping at the first thing that looks wrong.
Leaky ductwork is one of the more common reasons a system in an older home runs longer than it should without reaching the set temperature. Conditioned air escapes before it reaches the rooms it is supposed to serve, and the result is uneven temperatures and higher energy use. We inspect the duct system, seal leaks, and repair sections that have come loose or deteriorated. For homes with additions or rooms that were never properly connected to the main duct run, we assess what it would take to bring those areas into the system.
Zoning divides a home into independently controlled areas, each with its own thermostat or sensor. It is a practical answer for a house where one wing runs warmer than the other, or where different floors need different temperatures at different times of day. We handle zoning system installation and repairs, and we pair that work with smart thermostat upgrades when better visibility into how the system is running is part of what the customer is after.
the air conditioning page explains how the work is handled.
The call that comes in because something stopped working is usually the most urgent. A system that will not cool on a hot day or will not heat on a cold night moves to the front of the line. We diagnose the fault, explain what is causing it, and carry out the repair. If what we find points toward a larger issue, we say so before the work begins, not after.
A system that is running does not mean a system that is running well. A seasonal tune-up covers the components most likely to cause problems before they do: coil cleaning, refrigerant check, blower and airflow testing, ignition and flame sensor inspection, and thermostat calibration. For the homes in Terrell Hills that carry older equipment, a tune-up is also the best way to get a clear picture of what the system actually needs before something fails. We check the furnace. We check the AC. We leave it running right.
At some point, the repair math stops working. When a system is failing repeatedly, losing efficiency, or facing a repair that costs more than the remaining value of the equipment, replacement is the better answer. We assess the existing system, size the replacement correctly for the home, and handle the installation. The service page carries the full breakdown of what a replacement involves and what the process looks like from first call to startup. HVAC work sized and installed the way the manual calls for means the new system does what it is supposed to do from day one.
Affordable rates. Flexible timing. Reliable comfort.
Same-day service is often available, particularly for urgent repairs when a system has stopped working entirely. When you call, we confirm what appointments are open and let you know when someone can be out. We do not promise a specific arrival window, but emergency calls are prioritized during our hours, every day from 9:00 AM to 9:00 PM.
For properties with a tenant in place, we work around the schedule that keeps the situation manageable. A rental home without cooling in summer or without heat in winter is a situation that needs to be addressed quickly, and we handle those calls the same way we handle any emergency. For commercial properties or buildings that need to stay open during the work, we talk through the approach on the call.
Pricing is confirmed before we schedule. The technician explains what the diagnosis found and what the repair covers before any work begins. Local means we care what the neighbors think of our work, and that applies to every call we take in this town.
Terrell Hills carries a stock of homes that were built before modern HVAC equipment was standard. Some of that equipment is still in place. Older systems are not automatically worth replacing, but they do require a technician who is willing to work through the diagnosis rather than defaulting to a replacement recommendation.
Access matters too. Equipment in a tight attic space, a crawl space, or a utility closet that was not designed around serviceability takes longer to work on and affects what the job involves. We assess access as part of the diagnostic and factor it into the quote before any work is authorized. A property that is straightforward to work on and one that is not are priced accordingly, and we explain the difference on the call.
We serve Terrell Hills and the surrounding communities in Bexar County, including Alamo Heights, Olmos Park, Kirby, Windcrest, and San Antonio. Coverage across the area means the same heating and cooling work, the same pricing process, and the same technicians handling the job regardless of which town the property is in.
If you are in one of the surrounding communities and unsure whether we reach your address, call (830) 590-9782 and we will confirm. We're one phone call from getting your comfort right.
A system in a vacant property still benefits from a check before it is needed again. Equipment that has been sitting idle can develop issues that are not obvious until the system is asked to run. A pre-occupancy tune-up is a practical step before the property is used again, particularly after an extended vacancy.
Yes. A system that is running but not keeping the space comfortable is not doing its job, and the cause is usually diagnosable. Uneven temperatures, humidity that feels wrong for the thermostat setting, or a system that runs constantly without satisfying the space are all worth a call.
Often yes. When you call, we ask about the symptoms, how long they have been happening, and what the system was doing when the problem started. That conversation helps us understand what we are likely dealing with and come prepared. It does not replace the diagnostic, but it makes the visit more efficient.
A problem that shows up only after the system has been running points to a component that fails under heat or load conditions. Capacitors, motors, and electrical controls can test fine when cold and fail once they reach operating temperature. A technician who knows this will let the system run during the diagnostic rather than testing it cold and declaring it fine.
Older homes often carry duct systems that were sized for the original floor plan, not for additions or renovations that came later. Equipment that has been in place for many years may also be harder to source parts for, which affects whether a repair or a replacement is the more practical path. When we assess a system in a home like this, we look at the full picture before making a recommendation, because the right answer depends on the condition of the equipment and the ductwork together, not just the part that failed.
In most cases, yes. An older control may not communicate correctly with new equipment, and a smart thermostat or programmable control adds visibility and efficiency that a basic unit does not. We go over the control options as part of the installation conversation so you can decide what fits the property.
We work with the schedule that fits the property. When you book, let us know the access situation and any constraints around the tenant's availability. We are available every day from 9:00 AM to 9:00 PM, which gives us flexibility to find a window that works.
We are available every day from 9:00 AM to 9:00 PM, including weekends. If the system goes down outside those hours, call (830) 590-9782 when we open and we will work to get someone out the same day. For situations where the property is without heating or cooling and the conditions are urgent, same-day service is often available when you reach us at the start of the day.
Call (830) 590-9782 and describe what the property is doing. That is enough to get started. Magnum Heating & A/C handles the diagnosis, the repair, and the replacement work for homes and properties across Terrell Hills. We are available every day from 9:00 AM to 9:00 PM. Pricing is confirmed before we schedule, and the technician explains what was found before any work begins.
We protect your home. We service your system. We earn the call.
We also take work in: Alamo Heights, Kirby, Windcrest.
From a fast AC repair to a full system replacement, we handle the complete range of heating and cooling work for homes and businesses in Terrell Hills and across Bexar County. The table below covers what each service includes, who it fits best, and a practical note to help you decide where to start. Call (830) 590-9782 for a quote on any of these services.
| Service Type | Scope of Work | Common Needs | Helpful Details |
|---|---|---|---|
| Furnace & AC System Replacement |
| Homeowners whose repair costs are stacking up or whose system can no longer hold the set temperature | South Texas summers accelerate wear on older equipment, making timely replacement a practical choice |
| Heating & Furnace Repair |
| Any home or building that loses heat during a cold snap | Even mild Terrell Hills winters can make a furnace failure urgent on the coldest nights |
| Seasonal Maintenance & Tune-Ups |
| Any homeowner who wants to prevent breakdowns before the next season arrives | A spring AC tune-up and a fall furnace check are the two visits that prevent the most expensive repairs |
| Indoor Air Quality & Air Filtration |
| Households concerned about dust, allergens, or airborne particles indoors | An air quality upgrade is straightforward to add when the system is already being serviced |
| Ductwork Repair & Sealing |
| Homes where the system runs constantly but comfort is uneven from room to room | Sealing the duct system often makes a bigger difference in comfort than replacing equipment |
| Heat Pump Repair & Service |
| Homes running a heat pump for both heating and cooling | Heat pumps are a common fit in South Texas and benefit from annual inspection of both modes |
| Whole-Home Dehumidification & Humidity Control |
| Bexar County homes where high ambient humidity makes the indoor air feel uncomfortable even at the right temperature | Managing indoor humidity reduces extra load on the cooling system and improves overall comfort |
| Emergency HVAC Service |
| Any home or building where the HVAC system has stopped working and waiting is not an option | We take emergency calls every day from 9:00 AM to 9:00 PM and offer same-day service when available |
| AC Repair & Service |
| Homeowners and property managers whose AC stopped cooling or is underperforming | Same-day service is often available when the system goes down during peak summer heat |
| Thermostat & Smart-Control Installation |
| Anyone who wants better visibility and control over indoor temperature | A thermostat upgrade pairs well with ductwork improvements for room-by-room comfort control |
| Full System Installation & ReplacementMost Popular |
| Homeowners and commercial property owners replacing aging or failing equipment | We go over installation and replacement costs in plain terms before anything is scheduled |
| Heat Pump Installation |
| Homeowners replacing an older system or adding comfort to a new space in a mild-winter climate | Terrell Hills winters are mild enough that a heat pump handles both seasons efficiently from a single system |
Call (830) 590-9782 to talk through your system, get a straight answer on what it needs, and schedule service at a time that works for you.
(830) 590-9782