Code |
Name |
Description |
Temperature Range (°C) |
Pressure Range (bar) |
LTHW |
Low Temperature Hot Water |
Hot water system, typically at 40 ºC to 95ºC, used for space heating and / or low temperature processes and heat networks. |
40 - 95 |
1 - 16 |
MTHW |
Medium Temperature Hot Water |
Pressurised hot water system, typically at 96 ºC to 120 ºC, used for space heating and/or medium temperature processes and heat networks. |
96 - 120 |
1 - 16 |
HTHW |
High Temperature Hot Water |
Pressurised hot water system, typically at 121 ºC to 165 ºC , used for space heating and/or high temperature processes and heat networks. |
121 - 165 |
1 - 16 |
SS |
Steam Systems |
Steam system, typically used to supply heat directly to purpose designed heat emitters, process heat exchangers, hot water calorifiers and/or to subsidiary low temperature hot water systems via heat exchangers.
May also be used for kitchen equipment, humidification and sterilizing. Most systems other than those used for humidification or steam injection consist of steam supply with condensate return. |
100 - 200 |
0.5 - 16 |
CS |
Condensate Steam |
Condensate from steam systems (CS) - hot water generated from the condensation of steam to be returned to the boiler under pressure and/or gravity. |
96 - 120 |
1 - 16 |
DHWS |
Domestic Hot Water Services |
Hot water services system, typically stored and distributed at 60°C and used in domestic applications such as in sinks, showers and basins. Note: typically an open system. |
50 - 70 |
1 - 7 |
MCWS |
Mains Cold Water Services |
Water system supplied into a building from a local water utility network. Water is usually supplied at a minimum pressure of 0.7 – 1 bar. Note: typically an open system. |
7 - 20 |
0.7 - 5 |
BCWS |
Boosted Cold Water Services |
Water that is derived from a tank fed booster set to provide a constant supply of pressurised water to high-rise buildings where mains pressure is insufficient. Note: typically an open system. |
7 - 20 |
2 - 16 |
TCWS |
Tank Fed Cold Water Supply |
Cold (ambient temperature) water that is fed by gravity from a storage tank. |
7 - 20 |
0.2 - 3 |
CHW |
Chilled Water |
Chilled water that is cooled to below ambient temperature for use in comfort cooling and air conditioning. |
5 - 18 |
1 - 16 |
CCW |
Condensate Chilled Water |
Condensate from chilled water (CCW) - cold water generated from the condensation of moisture from humid air. |
7 - 20 |
0.1 - 1 |
HRW |
Harvested Rain Water |
Not to be confused with the recycling of “grey water”. HRW is the collection of water arising from atmospheric precipitation that is used in domestic water systems that do not require potable water quality such as laundry, WC flushing and garden watering. As such, it typically does not require chemical or biological treatment and can be left for longer period of time within pipes and tanks. |
7 - 20 |
0.2 - 10 |
GWR |
Grey Water Recycling |
Grey water recycling is the re-use of mains water that has already been used for washing purposes. Grey water systems are also non-potable and therefore may require sophisticated filtration and disinfection treatments before re-use, depending on the application. |
7 - 40 |
0.2 - 10 |
PW |
Potable Water |
Water suitable for human consumption that meets minimum legal requirements for wholesome water from mains or private extraction. It has been either treated, cleaned, or filtered, and meets local, established drinking water standards. Potable water is assumed to be reasonably free of harmful bacteria and contaminants and also considered safe to use in cooking and baking. |
7 - 69 |
1 - 10 |
R |
Refrigeration |
Artificial (human-made) process of using compressed gases for cooling a space, substance, or system to lower and/or maintain its temperature below the ambient one (while the removed heat is rejected at a higher temperature). This can be a specialised area, for more information please refer to: www.thebesa.com/academy/online-courses/f-gas-awareness-course/ |
-30 - 140 |
1 - 130 |
FO |
Fuel Oils |
Systems for the movement of oils, typically conventional gravity feed systems from a storage vessel, or oil transfer systems which transfer the oil from a bulk storage vessel to a daily service tank using a pump. Pumped circulation systems maybe either closed end or return to tank. |
5 - 90 |
0.2 - 5 |
FG |
Fuel Gas |
Systems used for the supply of fuel gas. Such systems are to meet the standard of the Institution of Gas Engineers and Managers (IGEM) and the Gas Safety (Installation and Use) Regulations. Such systems can include FG-NG (Natural Gas) and FG-LPG (Liquefied Petroleum Gas) |
5 - 23 |
0.001 - 16 |
MG |
Medical Gases |
A medical gas system is one that is manufactured, packaged, and intended for administration to a patient in anesthesia, therapy, or diagnosis. Medical gas supply systems in hospitals and other healthcare facilities are utilized to supply specialized gases and gas mixtures to various parts of the facility. Pipework designed and installed to meet the guidance given in HTM 02-01 2006. |
5 - 23 |
0.2 - 11 |
CA |
Compressed air |
Air that is compressed by a compressor to a pressure greater than atmospheric and distributed in a closed pipework system for various end-use industrial and process applications. |
7 - 50 |
1 - 16 |
FD |
Fire Defence |
Water based systems, including dry and wet risers, sprinkler pipework and associated fittings for protection of people, property and assets, against the risk of fire. |
7 - 20 |
2 - 16 |
AC |
Air Conditioning |
The process of removing heat and moisture from the air within the interior of an occupied space to condition, cool or improve the comfort of occupants or equipment usage. Typically, the pipework medium employed is via water or refrigeration. |
-20 - 140 |
1 - 130 |
HVAC |
Heating Ventilation and Air Conditioning |
Heating systems using either LTHW, MTMW, HTMW to increase temperatures for the comfort of occupants, and cooling systems which remove heat and moisture from the air within the interior of an occupied space to condition, cool or improve the comfort of occupants or equipment usage. |
-20 - 165 |
1 - 130 |