HVAC Frequently Asked Questions
Have any questions? Here are some of our most frequently asked questions about your AC, Heat, and smart home needs.
What is HVAC?
HVAC is short for Heating, Ventilation and Air Conditioning. HVAC is most often used to depict the whole heating and cooling system consisting of the duct work, air filters, humidification controls, and registers.
What is a Service Call Fee?
A Service Call fee is a bill for the expense associated with the time and travel to diagnose, inspect and provide expert recommendations for a home’s heating or air conditioning system by a certified professional technician.
What is a Precision Tune-up and how much does it cost?
An addition to the professional visual inspection included with our System Inspection, a Precision Tune-up also includes a total maintenance cleaning and lubrication of the heating or air conditioning equipment components.
Why is my AC system freezing up?
Low refrigerant: In some cases, freezing up is initiated by a leak in the refrigerant lines. Weak solder joints, friction from piping rubbing or vibrating against an object, leaking valves or loose fittings can cause leaks. The length of time your system has been installed and the nature and location of the leak are the determining factors on whether to have the system repaired or replaced.
Dirty evaporator coil: Over time, the evaporator coil will become dirty. On these occasions, the results are similar to those of having a dirty filter. Gradually you will lose airflow, slowly enough that you probably would not realize it until it freezes up or is not cooling adequately. You will need to contact your local Service Experts sales and service center to remedy the problem.
Defective blower motor or relay: A blower motor running at an improper speed or not running at all can cause freezing. It can also be sporadic, starting at full speed and slowing down after it heats up. Or a relay could cause it to start one time and not the next. In either case, you will need to contact your local Service Experts sales and service center to correct the problem.
Are all HVAC air filters the same?
No, HVAC air filters vary due to quality and size, and some have specs that others don’t. In most cases we recommend installing the filter your HVAC manufacturer recommends pairing up with your installed system, though you might be tempted to try some other filter type for convenience or to remove additional debris from your residence.
All filters have MERV ratings, which range from 1-20. MERV stands for “minimum efficiency reporting value”. A higher MERV rating means fewer particles pass through, and it catches finer particulates. This sounds fantastic, and it can be, but a filter that stops finer dust and dirt will also clog up quicker, and pressure on your unit will increase. If your system has not been crafted to operate with this kind of filter, it can reduce your airflow around your residence, putting the hurt on your comfort and energy costs. So what should you do? Unless you live in a hospital, you probably don’t need a MERV rating above 13. In fact, most residential HVAC systems are specifically designed to work with a filter with a MERV rating below 13, and frequently you will find that quality systems have been made to work with a MERV rating of 8 or 11. All filters with a MERV rating of five should catch most of the everyday nuisances people care about such as pollen, pet dander, and dust. While some filters claim to be able to catch mold spores, we recommend having a professional remove any mold from your residence you find, instead of trying to hide the issue with a finer filter.
How can I find carbon monoxide in my home?
The best method of detection is to use a carbon monoxide detector in a central location. A carbon monoxide detector is a device very similar to a smoke alarm. It monitors the air for carbon monoxide and emits an alarm if a specific level is detected. Ideally, you should have at least one detector adjacent to every living area, centrally located, or on each floor in your home. Carbon monoxide detectors are best when used in combination with a maintenance plan.
What is indoor air quality?
Indoor air quality (also called “indoor environmental quality”) describes how inside air can affect a person’s health, comfort, and ability to work. It can include temperature, humidity, lack of outside air (poor ventilation), mold from water damage, or exposure to other chemicals.
What is considered good IAQ?
The qualities of good IAQ should include comfortable temperature and humidity, adequate supply of fresh outdoor air, and control of pollutants from inside and outside of the building.
What are the most common causes of Indoor Air Quality problems?
The most common causes of IAQ problems in buildings are:
- Not enough ventilation, lack of fresh outdoor air or contaminated air being brought into the building.
- Poor upkeep of ventilation, heating and air-conditioning systems.
- Dampness and moisture damage due to leaks, flooding or high humidity.
- Occupant activities, such as construction or remodeling.
- Indoor and outdoor contaminated air.
Will the Nest thermostat work with my home?
If you have questions about whether Nest Thermostats will work with your home before you buy, use our Compatibility Checker. It’ll walk you through a few quick steps to determine whether your current furnace and/or air conditioning unit are compatible with the Nest thermostat. Find out at nest.com/compatibility.
If you want to see how it’s wired for each of our different models, follow this compatibility link. It’ll give you a wiring diagram that’s a great reference to use during the installation process.
Why doesn't the Nest control humidity based on outside temp?
This will prevent home damage cause by condensation. This seems like a no brainier to me. The Nest knows the outside temp, it just need to adjust the humidity accordingly. I just signed up for a 3rd party app that does this and much more. mynestreports.com If you have a humidifier or dehumidifier this app is a must, it does have other great features as well.
I checked my Nest app, and my Nest cam is offline. How do I fix this?
Do you see a yellow light on the front of your Nest cam? Perhaps you pulled up your Nest app, and you get a message that your Nest Cam is not connected to the internet? Don’t worry, we can get your Nest Cam back online!
1. Is your Wi-Fi working? Can you connect to Nest.com with another device such as your laptop? If you conduct the test using a mobile phone, make sure it is using Wi-Fi and not using cellular data to connect to the internet. After doing this test and your connection is still not working, try contacting your internet service provider to check the service status in your area.
2. Check the status of Nest services, by clicking here: https://nest.com/support/article/Troubleshooting-when-Nest-Cam-disconnects-or-is-offline-in-the-Nest-app#status If there is a problem with Nest’s camera service you might see the message, “The Nest service can’t be reached right now” in your Nest app. If you see this message, you will have to wait for the Nest service to resume.
3. Do you have the latest version of the Nest app? Here is the link to the apple store: https://itunes.apple.com/app/nest-mobile/id464988855?ls=1&mt=8 Here is the link to the Android store: https://play.google.com/store/apps/details?id=com.nest.android To make sure you have the latest version, you can uninstall and reinstall the Nest app.
4. Restart your Nest Cam. Restarting your camera will refresh your connection.
- Unplug your Nest Cam.
- Wait 10 seconds, then plug your Nest Cam’s back in.
- Your Nest Cam will restart automatically.
4. After restarting you should see a solid green light on the front of your camera to show that your Nest Cam is connected to your home Wi-Fi network. If you see another color light or no light at all on the front of your Nest Cam, follow this link for more info:https://nest.com/support/article/What-do-the-lights-mean-on-Nest-Cam
5. Restart your router. Restarting your router will restart your internet connection.
- Unplug your modem and router. All the lights from your modem and router should be off.
- Wait 30 seconds before plugging everything back in.
- Once the router finishes restarting, check your wifi connection.
6. Check to see if there’s enough internet bandwidth. Not having enough available bandwidth can cause connection issues with your Nest Cam. Learn more here: https://nest.com/support/article/Troubleshooting-when-Nest-Cam-disconnects-or-is-offline-in-the-Nest-app
7. Check for interference. There might be an object that is blocking your connection between the router and your Nest Cam, and all you might need to do is move your Nest Cam closer to your router.
8. Check the settings on your Wi-Fi router. Incompatible settings on your home Wi-Fi router or access point can cause your camera to disconnect or show up as Offline in the Nest App. Learn more here: https://nest.com/support/article/Troubleshooting-when-Nest-Cam-disconnects-or-is-offline-in-the-Nest-app
9. Check the incompatible list. It’s possible that your router might not be compatible with the Nest Cam. If your router is not compatible, all you will need to do is change some settings Learn more here: https://nest.com/support/article/Some-routers-may-cause-issues-with-adding-a-Nest-product-or-Wi-Fi-connections
Learn more: https://nest.com/support/article/Troubleshooting-when-Nest-Cam-disconnects-or-is-offline-in-the-Nest-app
How is Nest Cam IQ Outdoor different from Nest Cam Outdoor
|Nest Cam Outdoor||Nest Cam IQ Outdoor|
mount with hex
|Power cable runs along outside of your
|home Power cable can
be hidden behind
the mount for
|Plug-and-play installation: plugs into a
standard outdoor power outlet
into a standard
|Device||3-megapixel color sensor||8-megapixel (4k)
|8x digital zoom and enhance||12x digital zoom
|1080p HD video streaming||1080p HD video
Talk and Listen
HD Talk and
|Status light||Status light
RGB light ring
-4° to 104°F (-20° to 40°C)
-40 to 113°F (-40°
|IP65 rating (weather resistance rating)||IP66 rating
|Included features||Activity alerts||Person alerts|
|Available with Nest Aware||Person alerts||Familiar facealerts|
How can I tell that my Wi-Fi is good enough?
We recommend you have a broadband internet connection with at least 2 Mbps of upload speed for each Nest camera in your home (DSL connections may not have enough bandwidth). The Nest app will have you test your outdoor Nest Cam’s video stream in the location you’ve chosen before you install it.
When needed, the Nest app can automatically adjust the video quality so your camera’s video stream will be as smooth as possible. You can also manually change the video quality to use less bandwidth and lower your monthly data use.
Note: In the United States, outdoor Nest Cams can connect to both 2.4GHz and 5GHz wireless networks. Outdoor Nest Cams in Europe and Canada only connect to 2.4GHz networks.
Where should I install my outdoor Nest Cam?
Outdoor Nest Cams complement each other so you can choose to install one or the other in specific locations around your home, depending on what you want to keep an eye on.
For instance, Nest Cam IQ Outdoor’s design and advanced algorithms make it better suited for longer viewing distances with Supersight. It also has a louder speaker and three-microphone array. So if you want a camera to watch over your driveway, yard, or a piece of your property that’s a bit further away, a Nest Cam IQ Outdoor is probably a better option.
Nest Cam Outdoor is an excellent option for shorter distances where you don’t need the more powerful zoom, a automatic tracking of the IQ version. Because its operational temperature range is narrower, it can help to install it in a shaded spot under an eave or the porch roof.
General tips Even though our outdoor cameras are weatherproof, placing your camera under the eaves,roofline or another sheltered spot can help keep snow and rain off the lens.
You may want to point your camera at common intruder entry points: the front door, back door, windows, or garage.
Generally, it’s best to install your camera just above head height. 7 to 10 feet above the ground, tilted downward. This is high enough to let you see people’s faces and talk to them with the camera’s speaker and microphone.
Can I buy a Nest Protect and connect it to my existing smoke and carbon monoxide alarms?
Unfortunately, no, but this isn’t unusual. Each company’s smoke and CO alarms use proprietary detection algorithms and interfaces. And therefore, there’s no industry standard. If alarms from different companies are connected together, they may not warn you properly in an emergency.The NFPA actually prohibits the connection of alarms from different manufacturers without special testing. To the best of our knowledge, no company sells a combination smoke and CO alarm that is meant to be connected with a different company’s smoke and CO alarm. Some companies even state in their documentation not to connect to a different company’s smoke and CO alarm.
“Why do I need the Nest app to set up Nest Protect?”
You can install a Nest Protect without the Nest app. It will function as a standalone smoke and CO alarm and sound the alert if it senses a problem. If you have more than one Nest Protect,you need the app to connect them together and get all the features. After everything’s set up, the app lets you check the sensors and batteries whenever you’d like and get a message on your smartphone if something goes wrong at home.
“Why do I have to replace Nest Protect after seven years?”
Just like any electrical appliance, smoke and CO alarms wear out over time and must bereplaced before they’re unable to warn you in the event of an emergency. National standards and state laws require alarms be replaced when the sensors expire and most CO alarms have a lifespan of five to seven years.
Nest Protect has been fully tested by UL (U.S. and Canada) and BSI (Europe) and has an expected lifetime of seven years, based on the life of the CO sensor. To ensure your safety, Nest Protect checks its sensors constantly and sends you an alert when your alarm needs to bereplaced. Even if an alarm doesn’t have a CO sensor, laws require that smoke alarms be replaced every ten years.
Every time my furnace starts it makes a clicking sound, is that normal?
The clicking sound is likely the spark igniter on the furnace going through its sequence to light the furnace burners. This is normal. However, if you do experience louder and more frequent noises from your heating system you should contact your furnace repair technician for an
My furnace has a viewport with blinking lights, what do they mean?
This port is a diagnostic tool furnace & heating technicians use to help determine the operational status of the furnace.
What is the difference between an 80% and 90% furnace?
An 80% furnace is often less expensive, is usually vented with a metal pipe, takes air from indoors for combustion, and is generally less efficient. A 90% furnace typically costs slightly more, and is vented with an exhaust and intake PVC pipes (does not take air from indoors for combustion). Most models have variable speed blower motors and are two-stage or have modulating gas valves for maximum comfort.
What size furnace do I need?
Unless you are very familiar with HVAC industry energy standards and government energy standards, it’s almost impossible to determine the size of a replacement furnace. A trained heating specialist knows all the standards and can evaluate your home for not only the heating appliance, but also the quality of the heated air, and how well the air is distributed in the home. This evaluation is called a heating load calculation and should be performed by a heating and cooling contractor before they provide a new HVAC system quote.
This home heating evaluation also takes into consideration changes made to the home since the last furnace was installed. New windows, doors, insulation, exterior changes and other appliances that may have a huge effect on the size of the furnace needed today. A consumer can tell a contractor the exact furnace they now have, but without a complete home analysis, it’s impossible to determine the proper size of the replacement furnace equipment.
Why should I be concerned about the temperature in my attic?
A lot of people wonder why the temperature of their attic matters if nobody usually spends an extended period time in the attic. The reason why you want to control your attic temperature is because most attics are where air conditioning duct work starts.
If this ductwork is hot from sitting in a hot attic, heat will infiltrate your home’s air distribution system so that even if your thermostat is set to cool your home, the air coming out of your air registers will be warm. Heat can also infiltrate the rest of your home through conduction, where it moves through your attic’s floor and out of your ceiling.
How does a cooler attic save me money?
A cooler attic when it’s warm outside ensures that less heat penetrates your home’s ductwork so that the cool air coming out of your home’s air registers is about as cold as the air that passes through your home’s cooling coil.