Drayton LP111 Thermostat Wiring Diagram
Drayton LP111 timeswitch wiring
Wall plate with the 230 V mains and the changeover contact; choose how terminal 1 is fed.
Terminals and components · 6
- Live
- Neutral
- Common (COM)
- L–1 link
- OFF output
- ON output
Connection
Run the neutral from the same 230 V AC, 50 Hz circuit that feeds terminal L.
Function
Powers the internal clock. The output contact is volt-free: it only delivers 230 V if you fit the link between L and terminal 1.
Caution
- Installation must only be carried out by a qualified electrician or heating engineer.
- Switch off the mains before starting and before removing the unit; never fit it to a live wall plate.
- The mains input must have a 3 A fuse.
Earth
The unit is double insulated and needs no earth; the wall plate has an earth loop terminal to keep the cable's earth continuous.
L–1 link
With the link between L and terminal 1 (dashed line), outputs 2 and 3 deliver the 230 V mains live.
Caution
- Contact rating: 2(1) A at 230 V AC.
Separate supply
Without the link, the contact is volt-free: feed terminal 1 with the voltage it must switch, from a separate supply protected by a 3 A fuse.
Caution
- The 3 A fuse on the separate supply is required.
- Contact rating: 2(1) A at 230 V AC.
Use
Usually left free. Use it only if some equipment must be powered while the program is off.
Caution
- Contact rating: 2(1) A at 230 V AC.
Connection
Run this terminal to the control input of the equipment the timeswitch controls: the boiler, zone valve or hot water circuit (the LP111 controls heating or hot water, not both).
Caution
- Contact rating: 2(1) A at 230 V AC.
Use
The timeswitch doesn't use this terminal. When replacing another unit, you can use it to join a wire that must not connect to the timeswitch.
About This Diagram
This diagram is redrawn from pages 2–3 of the Drayton LP111 Thermostat Installation Instructions, and we offer it completely free and in English. We have also categorized it in the Thermostats (HVAC & Water Heating) section on Diagramverse, and it has been rated by 1 user with an average rating of 5.0. If you have any specific questions about the Drayton LP111 Thermostat Wiring Diagram, we suggest checking the Frequently Asked Questions (FAQs) section.
Printable Drayton LP111 Wiring Diagrams
Wiring Instructions
Before you start
The Drayton LP111 is a single-channel 24-hour timeswitch. It switches one circuit, either heating or hot water, up to three times a day. Only a qualified electrician or heating engineer should install it. It is designed for fixed wiring only, so it must be wired to current wiring regulations. It cannot be plugged into a socket. If you are not qualified, or your local rules require notification or a permit for work on fixed wiring, hire a professional.
Tools and materials:
- Insulated screwdrivers
- Wire strippers
- A voltage tester or two-pole tester
- A multimeter with continuity and AC voltage ranges
- Wall plugs and No. 6 x 1" (25 mm) woodscrews for a wall fixing, or M3.5 x 14 bolts for a flush single conduit box type UA1 (BS4662)
Do not use a surface-mounting box.
Cable: The documents give no conductor size. Use fixed-wiring cable sized to your local regulations for a circuit protected by a 3 A fuse. The mains input must be protected by a 3 A fuse, usually a fused spur or a mains isolator.
Location: The ideal height is about 1.4 m above the floor. Choose a spot with reasonable lighting, good access, no condensation and no extreme temperatures. The wall surface must cover the whole back of the unit. Leave 70 mm clear to the right of the wall plate and 25 mm above it, plus room underneath to reach the securing screws. Mount the wall plate with the terminals at the top.
Choose your variant. The output contacts are volt-free, so terminal 1 (COM) only carries what you feed into it.
- L–1 link (230 V output): Use this when the device you control needs a 230 V switched live. Typical examples are a combi boiler's switched-live input or a motorized zone valve.
- Separate supply: Use this when terminal 1 must be fed from a different circuit, which needs its own 3 A fuse. Use it also when the boiler handbook asks for a volt-free contact. In that case, do not link L to 1, and follow the boiler maker's instructions.
Step-by-step wiring
- Switch off the mains supply and remove the fuse from the fused spur. Use your tester to prove that every conductor at the wall plate is dead. If there is a separate supply, isolate that circuit too.
- If you are replacing an old timeswitch, loosen its securing screws and unplug it. The LP111 uses an industry-standard wall plate. If your old unit was also a Lifestyle LP111 or LP711, you can swap the units without disturbing the wiring. For other makes, check that each existing wire matches the function shown in the diagram: Neutral, Live, Common, On, Off or Spare. Move any wire that does not match.
- If you are fitting a new wall plate, fix it level with the terminals at the top. For surface wiring, snap out the cable entry strip on the bottom edge of the wall plate.
- Connect the mains neutral to Neutral (N).
- Connect the fused mains live to Live (230 V, 3 A fuse) (L). This only powers the clock.
- Feed the output common:
- L–1 link variant: fit a short link from L to COM · contact common (1).
- Separate supply variant: connect the separately fused live to terminal 1.
- Connect the wire to the boiler or valve's switched-live (call) input to ON · output while program is on (3).
- Use OFF · output while program is off (2) only if your system needs a signal while the program is off, such as the closing side of a valve. Otherwise leave it empty.
- Use Spare terminal (4) only to join wires that have to pass through the wall plate. It has no internal connection.
- The LP111 is double-insulated and needs no earth. If the cable has an earth conductor, join it on the earth continuity (loop) terminal so the circuit earth stays continuous.
- Tighten every screw, then tug each conductor gently to check it is held. Make sure no bare copper shows outside the terminals.
- Plug the timeswitch onto the wall plate and tighten the securing screws underneath.
Testing and start-up
- Before power-up: With the power still off and the unit unplugged, check continuity on the wall plate. In the L–1 link variant, L and terminal 1 should read as connected. Terminals 2, 3 and 4 should not be shorted to N or to each other.
- Power up: Check the 3 A fuse, refit it and switch on the mains. The display should light up. The clock is set at the factory and adjusts for summer time on its own. Check the time anyway, and correct it if needed through SET CLOCK?.
- Test the output: Press SELECT under the flap to choose ON. The red light should come on and the boiler or valve should respond. With the L–1 link, you should measure about 230 V AC between terminal 3 and N. Choose OFF and terminal 3 should drop to 0 V. In the separate-supply variant, terminal 3 shows whatever voltage is on terminal 1.
- Finish: Choose TIMED and set the three periods to suit the household.
Safety notes
- Every terminal can carry 230 V AC. In the separate-supply variant, terminals 1 to 3 may stay live after the timeswitch's own supply is switched off. Isolate both circuits before you work on it.
- Always switch off the mains before removing the timeswitch, and never fit it to a live wall plate.
- The contact is rated 2(1) A at 230 V AC. Do not switch a pump, immersion heater or other heavy load directly. Use a relay or contactor sized for that load.
- Run it within 230 V AC ±10%, 50 Hz. The operating temperature range is 0 to 45 °C.
- Repairs and maintenance must be done by a qualified electrician or heating engineer.
Troubleshooting
| Symptom | Probable Cause | What to Check |
|---|---|---|
| The display is completely blank | No mains on L and N, a blown 3 A fuse, or the unit not seated properly on the wall plate | Measure between L and N on the wall plate. You should see 230 V AC ±10%. Replace the fuse if it has blown, then refit the unit and tighten its securing screws. |
| The display and red light work, but the boiler never fires | No feed on terminal 1. The output contacts are volt-free, so terminal 3 has nothing to switch. | Check for the L–1 link or the separate fused supply on terminal 1. With the unit set to ON, you should measure about 230 V AC between terminal 3 and N. |
| Heating runs when it should be off and stops when it should be on | The output wire is on terminal 2 (OFF) instead of terminal 3 (ON) | Move the switched-live wire from terminal 2 to terminal 3, then test again in ON and OFF modes. |
| Heating runs all the time, whatever the program | The switched live has been joined straight to the permanent live, or the wire to terminal 3 is fed from somewhere else | Unplug the unit and check that the boiler's call wire only reaches terminal 3. It should not be joined to L or 1 at the wall plate or at a junction box. |
| Nothing works after I used terminal 4 for the supply | Spare terminal 4 has no internal connection | Move the supply wires to the correct terminals. Use terminal 4 only to join wires that pass through the wall plate. |
| The fuse blows as soon as I switch on | A short between L or 1 and N, or a stray strand touching a nearby terminal | With the power off, check continuity between every terminal pair and N. Re-strip and re-terminate any frayed conductor. |
| The boiler's low-voltage control input stopped working after I fitted the timeswitch | 230 V was fed into a boiler input that needs a volt-free contact, because the L–1 link was fitted | Remove the L–1 link and wire terminals 1 and 3 as a volt-free pair, as the boiler handbook shows. Have the boiler checked for damage. |
| Heating works intermittently, or the display flickers | A loose terminal screw, or the unit not tightened onto the wall plate | Isolate the supply, re-tighten all terminals and tug-test each wire. Tighten the securing screws underneath the unit. |
| The output switches but the boiler or valve buzzes, or the contacts fail early | The load is above the 2(1) A contact rating | Check the current drawn by the switched load. If it is above 2 A resistive or 1 A inductive, fit an interposing relay. |
| After swapping an old timeswitch, the system does the opposite of what I expect, or nothing at all | The old unit used different terminal numbers on the same wall plate | Compare each wire's function (Neutral, Live, Common, On, Off) with the diagram and move any wires that do not match. |
Frequently Asked Questions (FAQs)
My Drayton Lifestyle LP111 isn't working. What could be causing this?
Most LP111 faults come from the supply, the output feed or the mode setting. If the display is blank, check the 3 A fuse and make sure about 230 V AC reaches L and N. If the display works but nothing switches on, check that terminal 1 has a feed, either from the L–1 link or from a separate fused supply, because the contacts are volt-free. Then check that the output wire is on terminal 3, not 2. Finally, make sure the mode isn't set to OFF, and that the room thermostat or cylinder thermostat isn't holding the system off.
How do I set the time on my Drayton Lifestyle LP111?
Press SET? until the display shows SET CLOCK?, then press YES. The hour flashes: set it with the minus and plus buttons, and check AM or PM. Press SET? and set the minutes the same way. Press SET? again to reach SET DATE?, where you can set the year, month and day, and turn daylight saving on or off. When you press SET? at the end, the unit returns to normal operation. The clock is set at the factory and adjusts for summer time on its own, so it rarely needs changing.
Why is my Drayton thermostat not turning on heating?
The LP111 is a timeswitch, not a thermostat. It only lets the heating run during its ON periods. Check that the mode is TIMED, ONCE or ON. In the factory program, ON2 and OFF2 are set to the same time, so there is no midday period. Also check the room thermostat, because heating won't run if it has switched off. If the red light is on but the boiler stays off, check the wiring: terminal 1 needs a feed, and the boiler's call wire must be on terminal 3.
Should I use the L–1 link or a separate supply?
Use the L–1 link when the boiler or valve needs a 230 V switched live from the timeswitch, which is the usual combi boiler setup. Use a separate supply when the controlled circuit must come from a different circuit, which then needs its own 3 A fuse. If the boiler handbook asks for a volt-free contact, leave out the link and wire terminals 1 and 3 to the boiler as it shows. Never put 230 V into a low-voltage control input.
Does the LP111 need an earth connection?
No. The LP111 is double-insulated and does not need to be earthed. The wall plate has an earth continuity (loop) terminal so you can join the circuit's earth conductors and keep the earth continuous to the boiler or other equipment. Always join any earth conductors present in the cable rather than cutting them back. This keeps downstream equipment protected.
What load can the LP111 switch directly?
The LP111 contact is rated 2(1) A at 230 V AC. That means up to 2 A for resistive loads and 1 A for inductive loads such as motors or valve actuators. That is enough for a boiler's switched-live input or a typical motorized valve. For a pump, immersion heater or any load above the rating, the timeswitch should drive a relay or contactor that is rated for the load.
Can I fit the LP111 onto my old timeswitch's wall plate?
Usually yes. The LP111 uses an industry-standard wall plate, and many timeswitches share the same terminal layout. If the old unit was a Lifestyle LP111, LP711 or an Si version, you can swap the units without touching the wiring. For other makes, check that each wire matches the function in the diagram (Neutral, Live, Common, On, Off), and move any that don't. You need 70 mm of clearance to the right and 25 mm above the plate.
Will I lose the program or time during a power cut?
No. Without mains power the display goes blank, but the clock time and your program times are kept. When power returns, the timeswitch carries on with the correct time and program, with nothing to reset. It also changes between summer and winter time on its own, so you won't need to adjust it twice a year.
Can the LP111 control heating and hot water separately?
No. The LP111 is a single-channel timeswitch, so it controls either heating or hot water on one 24-hour program, the same every day. For different times on each day of the week, use the LP711. To time heating and hot water separately, you need a dual-channel programmer such as the LP241, LP522 or LP722. Those are wired differently.
What do the OFF, TIMED, ONCE and ON modes do?
The modes let you override the program without changing the stored times. OFF keeps the output off all the time. TIMED runs up to three periods a day. ONCE runs a single period from the start of ON1 to the end of OFF3. ON keeps the output on all the time. To change the mode, press SELECT under the front flap. Select TIMED to go back to your normal program. Advance only works in TIMED or ONCE.
Can I mount the LP111 on a surface box?
No, don't use a surface-mounting box. Fix the wall plate either straight onto a flat wall with wall plugs and No. 6 x 1 inch (25 mm) woodscrews, or onto a flush single conduit box type UA1 (BS4662) with M3.5 x 14 bolts. For surface cable runs, snap out the cable entry strip on the bottom edge of the wall plate. The wall surface should cover the whole back of the unit.
