CIBSE publishes several guides to HVAC design relevant to the UK market, and also the Republic of Ireland, Australia, New Zealand and Hong Kong. These guides include various recommended design criteria and standards, some of which are cited within the UK building regulations, and therefore form a legislative requirement for major building services works. The main guides are:
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).
Heaters exist for various types of fuel, including solid fuels, liquids, and gases. Another type of heat source is electricity, normally heating ribbons composed of high resistance wire (see Nichrome). This principle is also used for baseboard heaters and portable heaters. Electrical heaters are often used as backup or supplemental heat for heat pump systems.
Capacitors -- Capacitors help your HVAC motor start from a standstill. Over time they can weaken. As they weaken, they cause the motor to run hotter. This can shorten the life expectancy of your motor. Once a capacitor fails, the whole motor will stop working. You usually won't notice that a capacitor has weakened until your motor stops turning on.
They are also often harder to install. A proper location on the roof must be selected that can support the weight of the unit. Then a platform must be built and a drain pipe for the unit must be run along the roof to avoid problems with mold and corrosion. A crane must be used to lift the unit onto the roof while a team guides it into place and hooks it up.
So, the total price to a contractor for this project is $7,195.77 (Carrier is expensive), which we’ll use to calculate a fair HVAC installation cost. As I said, we typically use 40% in the industry to cover our own personal profit, as well as our insurance and other expenses. Let’s take a look at page three of a Final Report from our own online HVAC calculator, the HVAC Design & Consultation Program.
Some of these components can be repaired or replaced by the homeowner, such as filters, fuses, and clogged up drain lines. Coils, compressors and the other components are best left to a professional. In some cases, you may have a system that is so old that parts are no longer available or else they aren't up to code. In this case you will have to consider replacing the entire system.
Prices for central-air HVAC systems will vary. The national average to hire an HVAC specialist is $2,920-$3,670 but can run as high as $5,000 or even $12,000 depending on the capacity you need and other factors. Installing central air conditioning requires an entire system that works together to draw hot air out of your home. The system includes an outdoor unit, which houses the condenser and compressor, and the evaporator coils. If you don’t have an existing duct system, ductwork will need to be installed, which will affect labor and material costs. Leaking or damaged ducts will also need to be replaced.
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.