by Rich Gibson
Cooling and heating hire cuts across almost all of the UKs industry sectors, whether it be to replace faulty equipment already in place within a building, for ad-hoc usage or when emergency strikes. Business offices, food and beverage processing, hospitals and healthcare, education, corporate hospitality, facilities management, agriculture, warehousing, manufacturing and industry, to name but a few, all benefit from the ability to control their indoor environment using air conditioning, dehumidifiers, heaters and fans.
It is generally advisable to seek expert advice before selecting the model or models most appropriate to each situation or application. However, the internet allows most users to do a certain amount of their own research before contacting a supplier, so here is a list of some common definitions used within the cooling and heating industry to make that research just a little easier.
* R.H. – Relative Humidity is the relationship between the amount of water vapour in the air at any temperature and the maximum amount of water vapour which the air could absorb before condensation takes place. Relative humidity is expressed as a percentage.
* Dew Point – The temperature at which water vapour in the air condenses out.
* Vapour pressure – The partial pressure in the air due to the presence of water.
* Condensation – When humid air cools, the water vapour becomes liquid.
* Cold Bridge – An area of physical contact between a warm and cold surface where condensation occurs.
* Surface area – Length x Width = Metres2
* Volume – Length x Width x Height = Metres3
* Latent Heat – The heat required to evaporate or condense water with no change in temperature.
* K-factor – Heat transmission coefficient.
* Wet Bulb Temperature – Temperature of humid air with a thermometer with a wet covering around the mercury reservoir, at an air speed of +/-3 m/sec.
* Dry Bulb Temperature – Temperature of humid air, measured with a normal thermometer.
* Absolute Humidity – Amount of water vapour, expressed in kg, which is present per kg. of dry air.
* Psychrometric Diagram – A diagram in which a relation is given between the absolute and relative humidity at a specified pressure for each temperature.
* Pressure – Force per surface unit (n/m2 – PA).
As a rough guide, the Chartered Institute of Building Services Engineers recommends that 23C is the maximum temperature within a building and 16C is the legal minimum temperature required by the Health & Safety Executive.
Article submitted by Steve Reeve, Sales Director at Andrew Sykes. Andrews Sykes is the UK’s largest specialist hire company, with over 25 years experience. Serving virtually all industry sectors using machinery sourced from the worlds top manufacturers.