Page 681 - The City and Guilds Textbook: Plumbing Book 1 for the Level 3 Apprenticeship (9189), Level 2 Technical Certificate (8202) and Level 2 Diploma (6035)

Glossary

Noggin: a term often used on-site system and the heat exchanger of Sealed heating systems: heating
to describe a piece of wood that an indirect-type hot water storage systems that are sealed from the
supports or braces timber joists cylinder/vessel. It is called the atmosphere and operate under
or timber-studded walls. They are primary water because it is heated pressure. They do not contain a
particularly common in timber by the primary source of heat and feed and expansion cistern. Instead,
floors as a way of keeping the joists hot water in the dwelling, namely they have an expansion vessel to
rigid and at specific centres, but the boiler. The pipes that connect take up water expansion and a
they can also be used as supports the boiler to the heat exchanger filling loop to fill the system from
for appliances such as wash hand are called the primary flow and the the cold water main.
basins and radiators that are being primary return. The secondary water Semi-gravity system: a central
fixed to plasterboard. is the stored water in the cylinder heating system that has pumped
itself that is delivered to the hot
Nominal capacity: (of a cistern) the heating circulation but gravity hot
total volume it could hold when water outlets and taps. The primary water circulation.
filled to the top of the cistern. water heats the secondary water
indirectly via the heat exchanger. Sheath: insulation around the
Overheads: costs that include main copper cable, made from PVC
such things as site offices and staff Prohibit: prevent or forbid by law. plastic.
salaries. Qualitative method: divides Sheeting out: sheeting out a
risks into categories such as low,
Parasitic circulation: circulation tower scaffold means covering
that occurs within the same pipe; medium and high. the outside of the scaffold with
often called one pipe circulation. It Quantitative approach: ranking a tarpaulins. This can be extremely
generally occurs in open vent pipes risk with a number. dangerous as the tarpaulins act like
that rise vertically from the open Rectification: putting something the sails on a ship and could easily
vented hot water storage cylinder. right, correcting. blow the scaffold over.
The hotter middle water rises up Single feed, self-venting indirect
the vent pipe, and the cooler water, Regulatory body: an organisation cylinder: often referred to as the
towards the wall of the pipe, falls set up by the government to ‘Primatic’ cylinder, which is a trade
back to the cylinder. It can be a monitor, control and guide various name of IMI Ltd. Another version
major source of heat loss from hot sectors within industry. of this type of cylinder was also
water storage cylinders. Rippling: an unwanted, wavy available and may be found in
Permitted: being allowed to do pattern made on the inside face of some existing installations. It was
something. a machine bend when the bending known as the ‘Aeromatic’. It is
arm roller is not tight enough. slightly different from the Primatic
Plumb: when pipework is perfectly
vertical. Risk calculation formula: this because it has an air release valve
is a method of using a formula on the side of the cylinder near the
Portable appliance test (PAT test): of multiplying likelihood by heat exchanger to bleed air from
the process of checking electrical consequences to provide a number the heat exchanger.
appliances and equipment to that quantifies the level of risk for a
ensure they are safe to use. Soakaway: a pit, usually 1 m × 1 m
particular job. × 1 m, dug into the ground and
Potable: drinkable, from the French Rosin: a natural solid, resin-type filled with gravel, into which the
word ‘potable’, pronounced material obtained from pine rainwater pipe discharges. It allows
‘poe-table’. rainwater to soak naturally away to
trees, which, when heated, forms
Primary and secondary water: the acidic particles that can irritate the water table. A soakaway should
primary water is the water that the breathing. This could lead to be situated at least 5 m away from
is in the boiler, central heating occupational asthma. the property.

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