HRV/ERV Ventilators: These whole-house ventilators exchange air. They are ideal for homes with what is called a “tight envelope,” homes where house wrap has been applied and airgaps in the attic, around windows, doors and outlets have been sealed. Air in these homes becomes stale and polluted, so exchanging the air is important to IAQ. Heat recovery ventilators (HRV) are designed for cold climates. Energy recovery ventilators (ERV) are best for warm climates. Your cost for an installed HRV or ERV will range from about $2,000 to more than $5,000 based on its capacity and features.
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).
They work less jobs, thus increasing profits – think about it…if they got only half of the jobs, then they only pay half of the money required to pay employees, expenses, etc., but still have the same amount of net profit. In fact, if you do the math, they actually make more profit that their competitors do…twice as much, once you factor in their savings form only doing half of the jobs at the same amount of profit (Total Revenue – (half the normal expenses) = twice the profit). In other words, they save money by doing half of the jobs as others, for the same profit, thus increasing their overall profits.
Heating, ventilation, and air conditioning (HVAC) is the technology of indoor and vehicular environmental comfort. Its goal is to provide thermal comfort and acceptable indoor air quality. HVAC system design is a subdiscipline of mechanical engineering, based on the principles of thermodynamics, fluid mechanics and heat transfer. "Refrigeration" is sometimes added to the field's abbreviation, as HVAC&R or HVACR or "ventilation" is dropped, as in HACR (as in the designation of HACR-rated circuit breakers).
Without proper ventilation, carbon monoxide can be lethal at concentrations of 1000 ppm (0.1%). However, at several hundred ppm, carbon monoxide exposure induces headaches, fatigue, nausea, and vomiting. Carbon monoxide binds with hemoglobin in the blood, forming carboxyhemoglobin, reducing the blood's ability to transport oxygen. The primary health concerns associated with carbon monoxide exposure are its cardiovascular and neurobehavioral effects. Carbon monoxide can cause atherosclerosis (the hardening of arteries) and can also trigger heart attacks. Neurologically, carbon monoxide exposure reduces hand to eye coordination, vigilance, and continuous performance. It can also affect time discrimination.
I was disappointed with the pressure of a tub and shower that were plumbed with 1/2 supply lines (2nd floor). Could be low pressure from the street, but I want to replace with 5/8. Plus, I'd like to have 2 back to back showers, one inside and one outside. So, I had intended to bring a 1 supply to both, then branch up to valves and shower head with 5/8. Finally, I thought pressure from the street was typically 55 to 70 psi and I am concerned if pvc can take that.Any thoughts?
AC air handler squealing or grinding noises. Though most air handlers have direct-drive motors, some older units may be belt-driven. Squealing sounds from a belt-drive air handler generally occur when the belt that connects the motor to the blower slips. In most cases, the belt is improperly aligned or worn and needs replacement. Follow the instructions above under Air Conditioner Not Blowing Air and refer to your owner’s manual.
Consider what kind of heating and cooling system you want installed for the square footage of your home. Do you want a full system with a thermostat or a specific machine for the summer like a swamp cooler? Do you need a new furnace just for the winter? For any of these projects, the cost will vary depending on the quality, style and machine size you choose. If you have a tight budget, think of going smaller and upgrading over time. For example, if you can't afford to convert your entire home to solar power, you may want to consider only utilizing it to heat your water. Some other types of heating systems are:
At the state level the rebates are still substantial. For example, switching to a zoned system can get you a $100 rebate from various A/C companies, and state rebates are also included. In Pennsylvania a high-efficiency air conditioner alone can get you up to $300, and a high-efficiency complete HVAC system can see up to $1000. Maryland's incentives get up to $1,250, with a $100 rebate on a tune up of an existing system.
Reinstall the access panel and disconnect block. Turn on the circuit breaker and furnace switch. Then set the thermostat to a lower temperature and wait for the AC to start (see “Be Patient at Startup,” below). The compressor should run and the condenser fan should spin. If the compressor starts but the fan doesn't, the fan motor is most likely shot. Shut off the power and remove the screws around the condenser cover. Lift the cover and remove the fan blade and motor (Photo 7). Reinstall the blade and secure the cover. Then repower the unit and see if the fan starts. If it doesn't, you've given it your best shot—it's time to call a pro.
Indoor Fan Motor -- Indoor fans circulate the air from your house and through the system. Age and dust buildup are the two biggest contributing factors to their failure. When they are starting to fail they will often make noise. Failure of the fan will result in no heating or cooling, and if it is not repaired soon, it can cause other components to fail.
If the AC doesn’t turn off, it may be time to clean the condensing unit. Dirty condenser coils won’t give off heat efficiently and will keep the unit running. Another possibility: The contacts on the outdoor run relay may have welded together—something that can happen over time because of frequent electrical arcing at the relay. Before checking the run relay, turn off the power to the furnace and the condensing unit. Next, disassemble the relay and pry apart the contacts. This should do the trick until you buy a replacement—which you should do soon.
Lennox, on the other hand, is probably the most expensive unit out there and I can’t stand them. In our (humble?) experience, they have a horrible logistics chain, making repair parts difficult to come by (sometimes taking weeks), poor customer service, and the parts cost three times as much. That’s not what this article is about, so read more in: Carrier vs. Lennox Furnace Review.
Typically speaking, the lower SEER, more basic models are also more reliable. Reliability is big with us, so we steer clear of features with reliability issues, and it’s as simple as that. When you factor in the price of repairs and the extra expense of the 21-SEER, you may actually lose money! 16 SEER is the sweet-spot, and it is key to reducing your HVAC installation cost.
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.
In the United States, HVAC engineers generally are members of the American Society of Heating, Refrigerating, and Air-Conditioning Engineers (ASHRAE), EPA Universal CFC certified (for installation and service of CFC HVAC devices), or locally engineer certified such as a Special to Chief Boilers License issued by the state or, in some jurisdictions, the city. ASHRAE is an international technical society for all individuals and organizations interested in HVAC. The Society, organized into regions, chapters, and student branches, allows exchange of HVAC knowledge and experiences for the benefit of the field's practitioners and the public. ASHRAE provides many opportunities to participate in the development of new knowledge via, for example, research and its many technical committees. These committees typically meet twice per year at the ASHRAE Annual and Winter Meetings. A popular product show, the AHR Expo, is held in conjunction with each winter meeting. The Society has approximately 50,000 members and has headquarters in Atlanta, Georgia.
Consequently, this water must exit the air handler—typically through plastic pipe or a drain tube. That drain tube goes directly outside, often terminating near the compressor, or to a floor drain or to a small electric “condensate pump” located by the air handler. Where a condensate pump is used, it connects to a 1/2-inch vinyl or rubber tube that exits outdoors or to a drain.