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Revision as of 03:56, 18 November 2007 by John Rumm (talk | contribs) (added under construction header)
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Under Construction

This page is still being written, and has not had any form of review or comment.

Do not rely on any information presented here.

--John Rumm 03:56, 18 November 2007 (GMT)

This article discusses some of the many and varied ways in which thermostats are wired into domestic central heating systems.

<cautionary statements about mains voltages etc>

What does a thermostat actually do?

A thermostat is a simply a temperature controlled switch. In its simplest form the switch will default to closed or "On" until the stat reaches a preset temperature. Once it is warm enough, it opens or turns "off".

The temperature at which this happens is usually selected by a user adjustable control.

Do I need one

Cover heating system interlock, TRVs etc.

How many should I have

Discuss cylinder stats, multiple zones, UFH etc.

Types of thermostat

Mechanical Thermostats

diagrams and piccies of trad Honywell style stat

Programmable Thermostats

Wireless Thermostats

Thermostat features

Cover why there are a number of variations and explain things like:

  • Anticipator / Compensator heaters
  • Changeover contacts
  • Frost protection
  • Aux switching and contacts
  • Optimising stats

What does the thermostat control

  • Connecting to a boiler
  • Controlling a zone valve

How should I wire it

  • Type of cable
  • Earthing or lack of
  • what to do with spare neutrals

What else can I control with a thermostat

  • other apps including switching electric heating loads directly
  • cooling loads
  • over temperature alarms and sensors.