When a system stops working, the first question is almost always the same: can it be fixed, or does it have to go? That answer depends on the equipment, the fault, and whether a repair makes financial sense against what a replacement would cost. Magnum Heating & A/C handles both sides of that conversation for Selma homeowners, property managers, and commercial operators, and we give you a straight answer before anything is scheduled.
We cover the full range of heating and cooling work across Selma and the surrounding area. AC repair, furnace service, heat pump installation, ductwork, indoor air quality, and full system replacement are all part of what we do. Call (830) 590-9782 for a quote and we will confirm pricing before we book anything.
Not every HVAC call looks the same. A system that quit overnight is a different situation from one that has been struggling for weeks, and both are different from a property where the equipment is technically running but the rooms never get comfortable. The work that follows each situation is different too.
A system that stopped cooling or stopped heating usually has a diagnosable cause. Refrigerant leak diagnosis, a failing blower motor, a compressor that is drawing too much current, a heat exchanger that has cracked, a heat pump that will not switch modes. We trace the fault to its source rather than replacing components until something works. When the repair is straightforward and the equipment has useful life left, fixing it is the right call. We explain what we found and what the repair involves before any work is authorized.
A system that is running does not mean a system that is running well. Seasonal tune-ups catch the problems that are forming before they become the call you make at 8 PM on the hottest day of the year. We inspect, clean, and test the equipment, check refrigerant levels, measure airflow, and flag anything that looks like it is heading toward a failure. The service page carries the full breakdown of what a maintenance visit covers.
Some systems reach the point where the cost of keeping them going outpaces what a new system would cost to run. When that conversation comes up, we walk through the options clearly. What the new equipment would be, why it is sized the way it is, and what the installation involves. We do not push replacement when a repair is the honest answer, and we do not recommend a repair when replacement is the better path.
Replacing a system with the same size unit that was there before sounds logical. It is often wrong. A system that was undersized from the start, or one installed before the property was extended or modified, will repeat the same comfort problems in new equipment. Oversizing causes its own set of issues: short cycling, uneven temperatures, and humidity that the system never fully pulls out of the air.
We size replacement equipment to the property as it stands now, not to what the last unit happened to be. That means looking at the square footage being conditioned, the insulation and window situation, the ductwork layout, and the way the space is actually used. In a region where humid summers put real load on the cooling system, getting the sizing right is not a formality. It is the difference between a system that keeps up and one that runs all day without reaching the set temperature.
When heat pump installation is the right direction, the same sizing logic applies. A heat pump that is matched correctly to the home handles the long cooling season efficiently and manages the heating load without strain when temperatures drop. We confirm the right equipment for the property before anything is ordered.
A home that has never had central air, or one where the existing system has been removed, needs more than just equipment. The ductwork has to be in place and correctly sized, the air handler has to be positioned correctly, and the electrical and refrigerant connections have to be handled by qualified technicians. We manage the full installation, not just the unit itself.
Standard system filters catch some of what circulates through the air. Whole-home air filtration and air purification systems work alongside the existing HVAC equipment to address a wider range of particulates and airborne contaminants. Humidifier and dehumidifier installation fits into this category too. In a climate where summer humidity affects how comfortable a home feels even when the thermostat reads correctly, a whole-home dehumidifier is a practical addition rather than a luxury.
The air handler and blower motor are what actually move conditioned air through the property. A blower that is running slow, making noise, or drawing too much power affects comfort in every room the system serves. We diagnose and service air handlers and blower motors as part of repair calls and as standalone work when the symptoms point there.
A single thermostat controlling the whole property works until it does not. Zoning systems divide the home or building into independently controlled areas, which matters in a property where one part runs hot and another runs cold regardless of the setting. Smart thermostat installation and multi-zone controls are part of what we handle, and they pair naturally with ductwork corrections when airflow is part of the problem.
Leaking ducts are one of the most common reasons a system runs longer than it should without actually getting the space comfortable. Conditioned air escapes before it reaches the rooms it is supposed to serve, which means the equipment works harder and the result is still uneven. We inspect, seal, and repair ductwork as standalone work and as part of larger installation or replacement jobs. Your system is in good hands with us.
Calling an HVAC company doesn't have to be stressful, even when the situation is urgent. When you call, we ask about the system and the symptoms, confirm the rate, and book the appointment before the call ends. Same-day service is often available, particularly for repairs during the cooling season or a heating failure when the weather has turned cold.
For a property with no cooling or no heat at all, we prioritize those calls. A home that is not heating or not cooling is not a situation to leave until next week, and we take emergency calls every day from 9:00 AM to 9:00 PM. We are available seven days a week across that window.
For tenants, business operators, and rental properties where access needs to be coordinated, let us know the situation when you call. We work around occupied spaces and confirm what access is needed before the visit so nothing gets held up on the day.
Affordable rates. Flexible timing. Reliable comfort.
What a job costs depends on what it actually involves. A diagnostic and repair call is priced differently from a full system replacement, and the specifics of each job, what the fault turned out to be, how accessible the equipment is, and whether a repair or a replacement is the better answer, are what move the number.
We give you the rate on the phone, before anything is scheduled, so you know what the visit covers before anyone comes out. If the scope changes once the technician is on site, that conversation happens before any additional work is done. We do not present a bill that looks different from what was discussed. The service page carries the full breakdown of what different types of work involve. Call (830) 590-9782 and we will walk through what applies to your situation.
the page about heating and cooling covers the parts people usually ask about.
Uneven temperatures across a property almost always have a cause, and it is rarely the thermostat setting. The most common explanations are leaking or undersized ductwork that is not delivering enough airflow to certain areas, a system that is oversized for the space and short-cycling before it can pull humidity out of the air, or a zoning problem where one thermostat is trying to manage too many different spaces at once.
Mini-split and ductless systems are worth considering where a room or area simply cannot be reached by the central system, or where adding ductwork is not practical. A ductless unit conditions that space independently without touching the main system. We check the furnace. We check the AC. We leave it running right.
Whatever the cause, a diagnosis is where the answer starts. We look at the full picture, not just the equipment, before recommending what needs to change.
We provide heating and cooling service throughout Selma and the surrounding area in Bexar County. The communities nearby that we cover include Universal City, Live Oak, Garden Ridge, Schertz, and Converse. Residential homeowners, property managers, and commercial operators across this part of the county are all within our service area.
If you are in Selma or anywhere nearby and need HVAC service, call (830) 590-9782 and we will confirm coverage and get a quote started. Local means we care what the neighbors think of our work, and that applies to every job we take on across this area.
Call us. If the same symptom returns after a repair, we need to look at it again. A recurring problem after a repair can mean the original cause was not fully resolved or that a related component has since failed. We address it as a follow-up rather than treating it as a separate unrelated job.
Yes. The scope of the work does not change which locations we serve. Whether the job is a repair call or a complete installation, the service area is the same.
It is practical, not a pitch. A system that has been sitting idle through winter or summer may have developed a problem that will not show up until it is asked to work hard. A pre-season check is the best way to find out before the hottest or coldest day of the year becomes the day the system quits.
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.
Coverage does not depend on whether the property sits inside city limits or in an unincorporated area. What matters is whether the address falls within the area we serve. Call (830) 590-9782 with the address and we will confirm whether we can reach it.
In warm weather, a complete loss of cooling is treated as an urgent situation. We offer same-day service for no-cooling calls when same-day appointments are available. Call (830) 590-9782 and we will confirm what we can do and when.
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.
The scope of the job matters more than the square footage on its own. A repair call on a straightforward fault takes a fraction of the time a full system replacement does, regardless of how large the home is. When you call, we ask enough about the system and the situation to give you a realistic picture of what the visit involves before anything is scheduled.
We coordinate access with whoever needs to be on site. When you book, let us know whether access goes through the tenant or through you, and we will confirm what is needed before the visit. We work around occupied properties regularly and handle the scheduling in a way that does not require you to be there in person if the tenant can provide access.
It depends on the job and the time of year. A repair call is usually completed quickly enough that comfort is not significantly affected. A full system replacement takes longer, and on a hot day the interior will warm up while the equipment is disconnected. We work efficiently to minimize the time the system is out, and we let you know what to expect before the job starts.
When you call Magnum Heating & A/C, we will ask about the equipment, what it is doing or not doing, and how long the problem has been going on. From there we confirm the rate and book the appointment before the call ends. You will know what the visit covers, when to expect the technician, and what happens next.
Call (830) 590-9782 to get started.
We also take work in: Live Oak, Garden Ridge, Schertz.
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 Selma 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 Selma 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 | Selma 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