This one came in as a regular A/C service call in Cupertino, and it turned into a nice example of how much can get done in a single, well-planned visit. Our ductless AC repair work took about two hours on site. By the time we packed up, the outdoor unit had a fresh valve core and a proper R-410A charge, the furnace had its maintenance done, and the homeowner had a new ecobee thermostat they can control from their phone.
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The outdoor unit and what we worked on
The system’s outdoor unit is a TOSOT ductless condenser sitting on a balcony, with its own disconnect on the wall right above it. It’s a tidy spot, but a balcony means working carefully: tools laid out on a mat, nothing near the railing, and everything cleaned up before we leave.
Two line items on this job go hand in hand. First, we replaced a Schrader core on the service port. These little spring-loaded valves are what we connect our gauges to, and like any seal they can wear out over time. We did the replacement under pressure, using a core tool that lets us swap the core without recovering the whole refrigerant charge from the system. Less time, no wasted refrigerant, and no need to open the system up more than necessary.
Second, we charged the system with R-410A. We hooked up a digital manifold, watched the pressures and temperatures, and brought the charge to where it should be rather than guessing. A ductless system that’s low on refrigerant can still run, but it works harder and gives you less comfort for the same electricity.
Furnace maintenance and a smart thermostat
While we were there, the homeowner also asked us to take care of the furnace, so we did a full maintenance visit on it. Fall is honestly the best time for that: you find out about any issues before the first cold night, not during it.
We also installed an ecobee thermostat. The appeal is simple: you can adjust the temperature from your phone, set schedules that match your actual day, and stop heating or cooling an empty house. For a lot of Cupertino families it’s one of those small upgrades that gets used every single day.
Why we like visits like this
- One trip covers cooling, heating and controls, instead of three separate appointments.
- The valve core swap under pressure kept the refrigerant where it belongs.
- The charge was set with instruments, not by feel.
- The homeowner heads into the colder months with both systems checked.
If your mini-split isn’t performing the way it used to, or you’d like someone to look it over before the weather changes, take a look at our ductless repair service. We’ll tell you plainly what we find and what actually needs doing.
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Reviews
Trusted by your neighbors
“Honest and meticulous. They quoted me a competitive price for work that they expected to complete within a few days. The time to finish the job increased, but the price did not. It's clear that they are *very* careful and detail-oriented during installation. Fedor and the rest of the team also make everything before the work very easy; figuring out what you want, advising what to do, and communicating about scheduling/logistics. Very happy overall, would recommend them without hesitation. My wife and I have already used them twice: adding a central heat pump and later augmenting it, in select rooms, with mini splits.”
“We used Nur HVAC to replace gas furnace with a heat pump inverter, replace the aging duct work and gas water heater with a heat pump water heater, all in the same contract. Our project manager, Arthur was on-time for the scoping appointment. He took time to understand our needs, investigated the attic, ducts and all the existing equipment, before making any recommendations. He designed the optimal system for our house to be cost effective, provide highest comfort and be energy efficient. He was not pushy and was upfront about the ballpark estimates and timeline. He also walked us thru the various rebates that are available for the replacements from local utilities. Arthur's quote was very competitive, in fact better than those quoted to us by Costco referred contractors. Nur's installation crew - Eldar, Bhakridin, were very professional and thorough. They didn't rush the job and left the job site clean and clutter free each day. They accommodated our requests for placing the electrical wires and conduits so they are not in the way. All the equipment both indoor and outdoor were cleanly laid out, secured and wiped down before hand off. Always smiling and respectful, one of the best installation crew we have had. As a white glove contractor they took care of all the permitting, inspection paperwork w/ the city, all the paper work for us to receive the rebates. They even completed the warranty registration with the manufacturers for all the equipment! We would highly recommend Arthur and Nur HVAC to anyone in the Bay Area needing heating and cooling solutions. We would definitely be going back to them ourselves when the need arises.”
“This is the 2nd project I've done with NUR, and similar to the first time, I am a happy customer. From start to finish, NUR (in particular technician, Adlan) is completely professional. They are diligent and timely with their responses and scheduling. Adlan came out and diagnosed our 20 year old A/C system and was able to revive it, but prepared us with options for the future should the system go out again. He was extremely thorough in explaining these in layman terms. HVAC systems will always need maintenance and repairs, that's a given. However, I know that I have an honest, value-added, and well-run company to work with in NUR. Highly recommended!”
“Highly recommend Nur. From start to finish, this was an excellent experience. The sales guy, Fedor, did an excellent job explaining our options, giving us multiple quotes, and responding to my various follow up questions. Then, the installer, Islam, was super professional. He was very careful to protect my floors, to make everything look great, and to show me how to use the system. Most importantly, he discovered an oddity in my return ducts, having to do with an addition we did years ago. This required him to have to come back to relocate the air filter. Again, he was super professional through that as well. The price was very competitive and the service was top notch. Thanks and best wishes to the Nur team.”
Google Reviews
What our customers say on Google
“Phenomenal Service – Furnace Replacement & Heat Pump Installation! I can’t say enough good things about the team at Nur HVAC! They recently installed a brand-new AC heat pump system for us and replaced our old gas furnace, and the experience was top-tier from start to finish. The installation was completed with incredible attention to detail, craftsmanship, and professionalism. They found smart, creative ways to route all the new wiring while opening as few walls as possible. For the couple of small spots where wall access was necessary, they made sure everything was fully patched, finished, and painted so seamlessly you’d never know any work had been done. On top of that, what stood out the most was their commitment to going above and beyond—they stayed late working extra hours just to ensure our Google Nest thermostat was fully integrated, tested, and working perfectly before they left. It’s rare to find contractors who are this reliable, clean, knowledgeable, and genuinely dedicated to customer satisfaction. If you need any HVAC work done, save yourself the hassle and hire Nur HVAC. Outstanding job all around!”
“I highly recommend Islam from Nur HVAC to anyone needing reliable AC work. My AC went out and I had three different HVAC companies come by to look at it. None of them could fix the problem, and one company tried to tell me I needed a whole new zone board and two new dampers for several thousand dollars. Islam came out, listened carefully to everything I told him about what the previous technicans had said, and then did his own thorough troubleshooting. It was over 90 degrees out, and he spent time up in my hot, tight attic crawl space inspecting the indoor zone system and checking the outdoor condenser. He kept me updated the entire time on what he was testing and finding. Through his diagnosis, he proved that my dampers were actually working fine and that only the zone board needed to be replaced. Before doing any work, he gave me a clear quote upfront that came out to hundreds of dollars--saving me thousands compared to the other company. He installed the new board, double-checked that all the zones, thermostats, and dampers were working properly, and didn't leave until the system was running cold. Islam was punctual, polite, honest, and extremely hardworking. If you want AC work done right with technical competence and transparent communication, ask for Islam at Nur HVAC. I'll definitely be hiring him again.”
“Last month, we contracted NUR HVAC to install three units of Mitsubishi ductless AC units to our house. The sales contact Artur was very professional, always addressed our questions very quickly and clearly. Their office support Regina was proactive and timely communicated important information for our awareness ahead of time. Their two technicians Maxim and Alksei have done done an excellent job to install the units and relevant pipes. We are very satisfied with the quality of Nur HAVC's work, their competitive price and excellent customer services, and definitely recommend this company for others who are seeking professionals to do the similar service. George and Amy from Redwood Shores, CA”
“Nur installed and serviced our heat pump since the beginning of 2025. Quality of work, including the air handling, heat pump, ductwork, piping and electrical work was excellent. There were communication issues with the field crew but were ultimately resolved. Only with the recent warmer weather I used the cooling stage (instead of the heating) and came across a problem where it wasn’t cooling fast enough. Artur A. came back, checked all the vents and adjusted the air handling speed so it cools down much faster. Nur was responsive and fairly quick to correct our concerns. They were also quick to return and service our cooling issue. Thank you David and Artur A.”
“We replaced our 25-year old single phase gas furnace with a Mitsubishi HVAC heat pump this summer. Now that we’ve used it for both cooling and heating, I’d like to give the team at Nur a five-star rating for their clean, smooth installation. Communication was great and they were thoughtful about system design so that we don’t have exterior conduits. We are so happy with the operation of the system for heating: it is quiet and so much more effective than our old furnace. We can highly recommend Nur.”
“Loved my technician. Very honest. He replaced my gas heater and AC unit. Turned out great. Gas furnace wont be available after next year. So this should last another 25 years before I have to upgrade my panel to support a heat pump product. Dodged a bullet. I recommend this company. Susan Lacy Municipal Construction Inspector”
“After 18 years our Air Conditioning System failed. We, of course, called Nur HVAC and were glad to see Islam again. He rapidly diagnosed that the AC compressor failed and had to be replaced. However, the AC system was so old that the compressor only had a 1 year warranty and the refrigerant in use 18 years ago is only available for legacy repairs (This is to protect the Ozone layer). We could have replaced the AC system, but the heating system was equally old and likely to fail. The cost to move to a full all electric HVAC system was a few dollars more than just replacing the AC system and it would eliminate our use of gas for heating and take advantage of the recently installed Solar Panels. So the house has a new fully electric HVAC system installed by Nur HVAC. Islam came and took the measurements so the system could be ordered and priced. Soon Alex and the installation team arrived to install the system. The quality of the installation and the care Alex and team took during the custom wiring, new refrigerant lines, new moisture drains, new thermostats, system setup and calibration was outstanding. Alex made sure that the air flow for both heating and cooling was measured and far better than the previous systems. Alex made sure to keep us informed as progress was being made and they managed to keep the house clean during the install. Again Nur HVAC exceeded expectations with a very high quality install at a fair price. A project of this size had a few bumps but this appeared to have been done to provide a quality install with attention to detail. This company has superb knowledgeable professionals working for it from service to installation. I highly recommend Nur HVAC.”
“5/5 Stars - Highly Recommend Adlan and Nur HVAC! We had an exceptional experience with Adlan from Nur HVAC today. He is a consummate professional—extremely thorough, transparent, and honest. Our AC was completely out of refrigerant (6.5 lbs low), and instead of pushing an expensive and potentially ineffective nitrogen test on a hidden leak, Adlan gave us a practical, data-driven strategy to get our cooling restored for the summer while tracking down the issue. He thoroughly explained the system’s metrics, including a high compression ratio, and gave us fantastic, low-pressure advice on how to plan for our home’s long-term HVAC compliance and transition over the next couple of years. On top of that, he diagnosed a long-standing airflow bottleneck to our second floor. He took the time to inspect our complex crawlspace ductwork, confirmed the structural equipment is in great shape, and laid out a clear plan to return for a whole-house air balancing service. Finding a technician with this level of technical expertise and genuine integrity is rare. Request Adlan if you want the job done right. Thank you, Nur HVAC!”
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