Short course
Worcester wiring
In short
Circuits wired from the pages of Worcester's free wiring guide for its Greenstar boilers: combi, heat-only and system. Open the guide on Worcester's website, turn to the page, and wire the canvas the way it shows. DrawWarm is not part of Worcester Bosch and is not approved by it.
The jobs
Combi programmable stat (page 49)
A programmable room thermostat (stat) on a combi based on the Worcester Greenstar 4000. Take out the heating link, link the stat's live (L) to its common, and send its call to the live return (LR).
How it opensOpen Worcester's wiring guide and turn to page 49, "Greenstar CDi Combi: Programmable Thermostat". Keep it beside the simulator, and wire this canvas the way the page shows.
Combi timer and room stat (page 48)
A time controller and a room thermostat (stat) on the combi, joined in series by a wire connector. The live goes through both before it reaches the boiler's live return (LR).
Combi wireless stat (page 49)
A wireless room thermostat (stat) on the combi: its receiver is wired where page 49's programmable stat goes. Link the receiver's live (L) to its common (C), printed 1; its call goes to the live return (LR).
Combi two heating zones (page 45)
Two heating zones on the combi, each with its own time controller, room thermostat (stat) and zone valve. Both valves' end switches, the orange cores, meet on block 10, which feeds the live return (LR).
Combi frost protection (page 52)
A frost thermostat (stat) added to page 49's combi, already wired. It takes its live from the boiler's frost supply (FS) and sends its call to the frost return (FR).
Heat only single heating zone (page 12)
One time controller and one room thermostat (stat) on a heat-only boiler based on the Worcester Greenstar 18Ri. There is no zone valve: the stat's call goes straight to the boiler's live return (LR).
Heat only single hot water zone (page 11)
One time controller and a cylinder thermostat (stat) on a heat-only boiler based on the Worcester Greenstar 18Ri: hot water only. With no zone valve, the stat's call goes straight to the live return (LR).
Heat only S-Plan (page 5)
The S-Plan on a heat-only boiler based on the Worcester Greenstar 18Ri: a programmer, room and cylinder thermostats, and two zone valves. Both valves' end switches, the orange cores, meet on block 10 and feed the live return (LR).
Heat only Y-Plan (page 18)
The Y-Plan on a heat-only boiler based on the Worcester Greenstar 27Ri / 30Ri, with one 3-port valve. The boiler's own 230 V OUT feeds the wiring centre, and its pump block feeds the pump.
Heat only two radiator zones (page 8)
Two heating zones on a heat-only boiler based on the Worcester Greenstar 18Ri. Each zone has a time controller, a room thermostat (stat) and a zone valve. Both valves' end switches feed the live return (LR).
System single heating zone (page 36)
One time controller and one room thermostat (stat) on the DrawWarm System Boiler, in place of the page's Greenstar CDi System. Its pump is inside, so there is no pump to wire, and there is no zone valve.
System single hot water zone (page 35)
One time controller and a cylinder thermostat (stat) on the DrawWarm System Boiler: hot water only. With no zone valve, the stat's call goes straight to the boiler, and its own pump runs.
System S-Plan (page 29)
The S-Plan on the DrawWarm System Boiler, with two zone valves. The boiler's own 230 V OUT feeds the wiring centre, and its pump is inside, so there is no pump to wire.
System Y-Plan (page 30)
The Y-Plan on the DrawWarm System Boiler, with one 3-port valve. The boiler's own 230 V OUT feeds the wiring centre, and its pump is inside, so there is no pump to wire.
System two heating zones (page 32)
Two heating zones on the DrawWarm System Boiler. Each zone has a time controller, a room thermostat (stat) and a zone valve; the boiler's own 230 V OUT feeds the wiring centre.
You will learn to
- Read a boiler maker's wiring page and wire the circuit it shows
- Wire a combi with a programmable stat, a timer and room stat, a wireless stat, two heating zones and a frost stat
- Wire a heat-only boiler and a system boiler for one heating zone, one hot water zone, an S-Plan, a Y-Plan and two heating zones
- Feed the controls from the boiler's own 230 V OUT where it has one, and take out a combi's heating factory link
Checks and credit
- Also a short course on its own, Worcester wiring, with credit both ways.
Practise it in the simulator.
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