A horizontal gas flue that has concentric
tubes, i.e. one inside the other, arranged in this way so that one
tube carries out the exhaust fumes and the other brings in the air
for combustion. The combustion chamber is thus room-sealed and safe.
Thermal Units. A measurement of heat output now replaced by kW. 1
Btu / Hr = 0.000293kW. A 90,000BTu boiler is approximately 26kW.
The outside unit in an air-conditioning system
that disperses the waste heat and condenses the gas back to a liquid.
trade name for flue liners made from flexibly jointed stainless steel.
This is used to line brick flues to prevent carbon monoxide leaking
into the house.
A central heating system that does not use
pumps but circulates the water by gravity and water expansion.
indirect tank under Plumber.
measurement of power, which may be expressed as energy, consumed in
a period such as kW/hrs.
term given to a group of bacteria that thrives in water of between
15 and 450C. The bacteria can infect susceptible people and result
in an illness similar to pneumonia. The bacteria has been found in
shower heads and it is therefore a good idea to have the domestic
water supplies from storage systems regularly flushed professionally
if there are persons using systems who are elderly or with health
problems. The systems particularly prone are older mixers where the
hot and cold are mixed remote from the head.
A hot water and radiator system that has a
sealed pressure vessel to deal with expansion and a safety valve to
prevent damage. The advantage is that higher temperatures can be reached,
a header tank does not limit the height of radiators and the system
can be compact for flats. The system does need special approval from
the local council building control.
A term used to describe comfort cooling, commonly
termed "air-conditioning", where the room evaporator and
the outside condenser are split and not within a combined unit.
Thermostatic radiator valve. A room temperature
sensing valve on a radiator, which locally switches off the radiator
at a preset temperature.