A pinging or popping sound coming from the duct work can come from thermal expansion—the ductwork expanding and contracting as it heats and cools.  Or, air blowing past a loose flap of metal can make the sound. Track along the duct runs, listening for the sound. If you locate it, make a small dent in the sheet metal to provide a more rigid surface that’s less likely to move as it heats and cools.
Furnaces and thermostats are not mix-and-match appliances. Using the wrong type of thermostat with a furnace will cause operating problems and can be dangerous. Although thermostats look similar, they are designed very differently. There are numerous types of heating systems and thermostat systems and they need to be coordinated for safe and proper operation. There are three types of thermostat systems used today: millivoltage, low voltage, and line voltage.​
The most recognized standards for HVAC design are based on ASHRAE data. The most general of four volumes of the ASHRAE Handbook is Fundamentals; it includes heating and cooling calculations. Each volume of the ASHRAE Handbook is updated every four years. The design professional must consult ASHRAE data for the standards of design and care as the typical building codes provide little to no information on HVAC design practices; codes such as the UMC and IMC do include much detail on installation requirements, however. Other useful reference materials include items from SMACNA, ACGIH, and technical trade journals.
The heat-exchanger cools the air that is being forced through it by the furnace blower. As the warm air comes in contact with this cool surface the water in the air condenses. By pulling the water molecules from the air. According to the psychometric chart[42] as relative humidity decreases in order to feel cool you will have to lower the temperature even more. A common way to counteract this effect is by installing a whole-home humidifier.[43] Similarly, installing a high efficient system this need to turn the temperature down wont have such and influence on your energy costs.
Although HVAC is executed in individual buildings or other enclosed spaces (like NORAD's underground headquarters), the equipment involved is in some cases an extension of a larger district heating (DH) or district cooling (DC) network, or a combined DHC network. In such cases, the operating and maintenance aspects are simplified and metering becomes necessary to bill for the energy that is consumed, and in some cases energy that is returned to the larger system. For example, at a given time one building may be utilizing chilled water for air conditioning and the warm water it returns may be used in another building for heating, or for the overall heating-portion of the DHC network (likely with energy added to boost the temperature).[4][5][6]

Locally owned and family operated, M and M, Heating & Cooling, Plumbing & Electrical customizes solutions to perfectly fit your requirements and lifestyle. We specialize in a wide range of services including plumbing, water heating, indoor air quality, and residential and commercial temperature control. Our team of highly trained and certified technicians are fully licensed and insured, adhere to strict service procedures, and meet exacting standards of quality. Call on M and M, Heating & Cooling, Plumbing & Electrical at (720) 443-6119 for dedicated service throughout Longmont, CO & surrounding areas, and have confidence in a rewarding experience and long-term results. With over eighteen years of satisfied customers, we take great pride in a job done right.
Central, "all-air" air-conditioning systems (or package systems) with a combined outdoor condenser/evaporator unit are often installed in North American residences, offices, and public buildings, but are difficult to retrofit (install in a building that was not designed to receive it) because of the bulky air ducts required. (Minisplit ductless systems are used in these situations.) Outside of North America, packaged systems are only used in limited applications involving large indoor space such as stadiums, theatres or exhibition halls.

As a Carrier Factory Authorized Dealer, M and M, Heating & Cooling, Plumbing & Electrical is qualified to properly size and install the most technologically advanced and well-regarded heating, cooling, and air quality products on the market today. Our team is NATE-certified, factory trained, EPA certified, and regularly updated, ensuring the right solution to any challenge.


AC air handler buzzing sounds. Do you hear a buzzing sound when you turn on the thermostat? The only thing that comes on in the house when you turn on the thermostat is the fan relay and fan in the air handler or furnace. Try switching the thermostat HEAT/COOL switch to OFF. Then switch the fan switch from AUTO to ON. The fan (only) should come on. If the air handler makes a buzzing sound, it probably has a bad fan relay or, more likely, blower fan.
Many disconnect blocks contain two cartridge fuses. Check them before you proceed with repairs (Photo 3). A blown fuse is a sign of a failing part inside the condensing unit. So don’t just replace it and think you’ve solved the problem. Instead, replace the parts we show here. Then install new fuses and fire up the unit. If it blows again, call a pro—you’ve got more serious issues.

Clean air delivery rate is the amount of clean air an air cleaner provides to a room or space. When determining CADR, the amount of airflow in a space is taken into account. For example, an air cleaner with a flow rate of 100 cfm (cubic feet per minute) and an efficiency of 50% has a CADR of 50 cfm. Along with CADR, filtration performance is very important when it comes to the air in our indoor environment. Filter performance depends on the size of the particle or fiber, the filter packing density and depth and also the air flow rate.[31]
Air conditioning and refrigeration are provided through the removal of heat. Heat can be removed through radiation, convection, or conduction. Refrigeration conduction media such as water, air, ice, and chemicals are referred to as refrigerants. A refrigerant is employed either in a heat pump system in which a compressor is used to drive thermodynamic refrigeration cycle, or in a free cooling system which uses pumps to circulate a cool refrigerant (typically water or a glycol mix).
Before selecting the installation location of air conditioner, several main factors need to be considered. First of all, the direction of air flow from the indoor units should not fall on the place of rest or work area. Secondly, there should not be any obstacles on the way of the airflow that might prevent it from covering the space of the premises as much as possible. The outdoor unit must also be located in an open space, otherwise the heat from the house will not be effectively discharged outside and the productivity of the entire system will drop sharply. It is highly advisable to install the air conditioner units in easily accessible places, for further maintenance during operation.
You can usually slip the belt on the motor’s (smaller) pulley first and then start it on the blower pulley. Rotate the blower pulley by hand, holding the belt in place but keeping your fingers from getting caught between the belt and the pulley. The belt should slip right into place. If it seems to be too tight or difficult to set in place, it may be necessary to adjust the motor mount to provide more slack.

When your furnace isn’t regularly serviced it can operate less efficiently. This increases your energy bills and also prevents your furnace from keeping your home as warm as you like. Keep your furnace properly maintained with regular service. The national average furnace service cost is between $60 and $80. Companies may offer tuneup specials that cover all the necessary testing, tightening, measuring and cleaning to keep your equipment running at top efficiency. If you have a newer system, furnace service costs may be covered by your warranty. Outside of warranty, a basic tuneup might start at $58 and a more advanced maintenance cleaning could be over $120. Here are some signs your furnace may need service:
Aurora residents are well aware that when the furnace goes out in their home, can be incredibly frustrating to get working again. At times, there are serious things that go wrong with a home that needs to get fixed very quickly. As far as the furnace goes, it needs to get repaired or fixed as soon as possible, which is why it’s good to know that our furnace repair company does furnace replacement in Aurora and also Aurora furnace repair, is prepared to help at any time. To learn more about our furnace and heating services, click HERE today! 

Aurora residents are well aware that when the furnace goes out in their home, can be incredibly frustrating to get working again. At times, there are serious things that go wrong with a home that needs to get fixed very quickly. As far as the furnace goes, it needs to get repaired or fixed as soon as possible, which is why it’s good to know that our furnace repair company does furnace replacement in Aurora and also Aurora furnace repair, is prepared to help at any time. To learn more about our furnace and heating services, click HERE today!
In 1906, Stuart W. Cramer of Charlotte was exploring ways to add moisture to the air in his textile mill. Cramer coined the term "air conditioning", using it in a patent claim he filed that year as an analogue to "water conditioning", then a well-known process for making textiles easier to process. He combined moisture with ventilation to "condition" and change the air in the factories, controlling the humidity so necessary in textile plants. Willis Carrier adopted the term and incorporated it into the name of his company.[10]
The liquid refrigerant is returned to another heat exchanger where it is allowed to evaporate, hence the heat exchanger is often called an evaporating coil or evaporator. As the liquid refrigerant evaporates it absorbs energy (heat) from the inside air, returns to the compressor, and repeats the cycle. In the process, heat is absorbed from indoors and transferred outdoors, resulting in cooling of the building.
Energy efficiency can be improved even more in central heating systems by introducing zoned heating. This allows a more granular application of heat, similar to non-central heating systems. Zones are controlled by multiple thermostats. In water heating systems the thermostats control zone valves, and in forced air systems they control zone dampers inside the vents which selectively block the flow of air. In this case, the control system is very critical to maintaining a proper temperature.

HVAC repair technicians are properly qualified to take care of anything that relates to installing, maintaining or repairing your heating, air conditioning and refrigeration systems. Our professionals have gone through rigorous training and certification and all our technicians and equipment installers are NATE-certified, which involves demanding testing and indicates a solid understanding of the industry.

Air conditioning (often referred to as AC, A/C, or air con)[1] is the process of removing heat and moisture from the interior of an occupied space, to improve the comfort of occupants. Air conditioning can be used in both domestic and commercial environments. This process is most commonly used to achieve a more comfortable interior environment, typically for humans and other animals; however, air conditioning is also used to cool/dehumidify rooms filled with heat-producing electronic devices, such as computer servers, power amplifiers, and even to display and store some delicate products, such as artwork.


Air flow meter Aquastat BACnet Blower door Building automation Carbon dioxide sensor Clean Air Delivery Rate (CADR) Gas sensor Home energy monitor Humidistat HVAC control system Intelligent buildings LonWorks Minimum efficiency reporting value (MERV) OpenTherm Programmable communicating thermostat Programmable thermostat Psychrometrics Room temperature Smart thermostat Thermostat Thermostatic radiator valve
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