Important Notes:

Make the electrical provision as per the diagram Fig.1. The circuit must incorporate a 30mA RCD protection.
For installations below 13 Amp, A fused spur or combined spur / RCD is recommended.
For installations over 13 Amp a suitable isolated supply should be provided incorporating 30 mA RCD protection.
The thermostat rating is 15 amps & this is capable of controlling approx 3450 watts of heating. (most domestic installations are within this figure). If the system supplied is over 3.45 kW it will be subject to a more comprehensive electrical installation. (Your electrician will be able to advise you on this).
Note: all electrical connections should be made in compliance with building regulation Part "P" and current wiring regulations.
Note if installing in a bathroom or other "wet" room the thermostat must be located OUTSIDE of the room, on the opposite side of the wall, for example in a bedroom or hallway / landing.

STEP 1

First prepare the sub-floor ensuring that it is clean and free from grease, dirt or debris. Fig.2
Note - if installing on a bitumen base, this must either be removed or covered. For further information, refer to the FAQ’s on the back page of this manual or contact the floor heating helpline.
The most suitable sub-floors are: concrete, tile-backer boards, existing tiles, water-resistant timber e.g. WBP Ply.

STEP 2

If fixing tile-backer boards, do so in accordance with the separate instructions provided, using tile adhesive on a concrete sub-floor Fig. 3, or galvanised screws with washers/fixings on timber sub-floors.

STEP 3

Prime the floor or the tile backer boards using the Acrylic primer contained in the kit. If installing over a large area or on an absorbent surface the primer may need to be diluted in accordance with the primer instructions. Once primed leave to dry (typically 1-3 hours) and avoid foot traffic over this area. The purpose of priming is to promote greater adhesion and reduce the amount of moisture absorbed into the sub-floor Fig. 4. Before proceeding to step 4 see note below

STEP 4

Calculate the cable spacing. This is a very important step and MUST be done correctly to ensure all the cable is used up and avoid extra work later.
First measure the area to be heated in m² (do not include the area taken up by fixed objects such as baths / showers and kitchen units), then divide this area by the length of the cable shown on the drum. The cable is 10 watts per linear meter so, for example, a 750 watt kit contains 75 m of heating cable.
The spacing is calculated by dividing the total m² of the area to be heated by the cable length in m. Example Fig 5.

STEP 5

Once the spacing has been determined, leaving a perimeter of 3-5 cm around the edge of the room, mark out on the floor at the calculated intervals. This will usually be between 6 and 8 cm Fig 6.
If your calculated spacing is less than 5 cm STOP and do not install – the kit size is too large for the room.
A spacing of 10 cm will in many cases only take the chill off the floor. Used as a heating source in most domestic situations the spacing should be between 6-8 cm (this is always dependent on insulation levels and type of floor construction).

STEP 6

Test the resistance of the cable prior to installing, Fig 7 and ensure that the reading is as per manufactures design reading This can be found on the silver label on the packaging or printed on the PVC sheath (± 10%). Make a note of the reading. Test the insulation of the cable by checking that there is no electrical continuity between each of the conductors and the earth braid. If you find there is continuity contact your underfloor heating supplier or the floor heating helpline printed on the back of these instructions.

Do not tile over the cable without testing it.

STEP 8

Adjust the spacing if necessary to ensure all the cable is used up and the floor has an even covering.
Cables should be spaced no closer than 50 mm (5 cm). Tape over the cable at regular intervals ensuring that it is well secured to the floor Fig 10.

STEP 9

Test the resistance of the floor probe. Refer to the label on the floor probe wrapper for desired resistance readings. Make a note of the reading.
Position the sensor between two runs of cable, in a position that will not be covered by rugs or low profile furniture. Once a suitable location is established, tape into position Fig 11. The sensor wire should not cross the heating cable at any point. The sensor wire can be shortened or if necessary,

STEP 11

If possible cover the cables with a thin layer of flexible levelling screed (3-4 mm) this will help protect the cables when tiling Fig 12. Suitable products will usually be available from your tile supplier. If you have any difficulties refer to FAQ’s on the back page of this manual or contact the floor heating helpline. If you do not wish to use a levelling screed, you may tile directly over the cables in a single operation, however extra care must be taken not to damage or
dislodge the cables.
Tile the floor using a flexible tile adhesive and grout as per industry standards and the manufacturers instructions. If you are using a suitable vinyl or thin carpet as the final flooring we recommend a minimum of a 6 mm layer of levelling screed over the cables to ensure even heat distribution.

• DON’T Attempt to cut the heater cable at any point
• DON’T Allow the wires to cross or touch
• DON’T Allow excessive foot traffic over the wire before tiling
• DON’T Cut tiles directly over the cable
• DON’T Place tools or stacks of tiles on top of the cable
• DON’T Turn the system on until the floor covering has been laid and allowed time to set.

Example 1: Fig. 13

Typical mat installation in a rectangular shaped room.

Example shown is a 5m² cable mat (10m total length of mat)

divided into 5 runs each of 2m long with a 50mm gap between each run of matting to maintain minimum cable spacing

Thermostat
Cold Cable Joint
Sensor Tip

Example 2: Fig. 14

A sample mat installation in a kitchen.
Example shown is a 2.5m² cable mat
(5m total length of mat)
3 full width runs each laid to maintain a 50mm gap between cable loops. Two of the mat runs are approximately 2.2m long and the third run is 0.9m. The remainder of the cable is removed from the mesh matting, laid loose and fixed in place with self adhesive cloth tape (duct tape). When run loose, the cable should be spaced, similarly to when it is attached to the matting. Cables should be spaced no closer than 50mm.

Example 3: Fig. 15

Typical bathroom installation:
Example shown is a 2.5m² cable mat
(5m total length of mat)
2 full width runs in front of the bath, each laid to maintain a 50mm gap between cable loops. Areas where a full width of mat cannot be laid, the cable is removed from the mesh matting, laid loose and fixed in place with self adhesive cloth tape (duct tape). When run loose, the cable should be spaced, similarly to when it is attached to the matting. Cables should be spaced no closer than 50mm. Matting can also be laid 90° to main runs of matting.

Example 4: Fig. 16

Victorian Style Conservatory installation:
Example shown is a 9m² cable mat
(18m total length of mat)
6 full width runs of mat, each laid to maintain a 50mm gap between cable loops. The angled sides of the room create irregular areas which can be filled by removing the cable from the mesh matting, laid loose and fixed in place with self adhesive cloth tape (duct tape). When run loose, the cable should be spaced, similarly to when it is attached to the matting. Cables should be spaced no closer than 50mm. be laid 90° to main runs of matting.

Example 5: Fig. 17

Multiple mat installation:
Example shown is a 13m² cable mat
(14m+12m total lengths of mat)
8 full width runs of mat, each laid to maintain a 50mm gap between cable loops. As the thermostat is located at one end of the room, the matting has been laid so that the cold tails from each mat can be connected directly into the thermostat without the need to extend the cold tail.

STEP 5

Test the resistance of the cable mat prior to installing and ensure that the reading is as per manufactures design reading. This can be found on the silver label on the packaging or printed on the PVC sheath (± 10%). Make a note of the reading. Test the insulation of the cable by checking that there is no electrical continuity between each of the conductors and the earth braid. If you find there is continuity contact your underfloor heating supplier or the floor heating helpline printed on the back of these instructions.
Do not tile over the cable without testing it.

STEP 8

Test the resistance of the floor probe. Refer to the label on the floor probe wrapper for desired resistance readings. Make a note of the reading.
Position the sensor between two runs of cable, in a position that will not be covered by rugs or low profile furniture. Once a suitable location is established, tape into position Fig 21. The sensor wire should not cross the heating cable at any point. The sensor wire can be shortened or if necessary, lengthened with 2 core flex cable minimum 0.75mm² to a maximum length of 50m. If you need to cut the sensor wire you must only cut the cable end. DO NOT cut the end which contains the plastic floor sensor.

STEP 9

Test the cable mat resistance and the cable insulation along with the floor probe immediately prior to tiling to ensure that neither has been damaged. Compare readings with those recorded earlier.

STEP 10

If possible cover the mat with a levelling screed (3-4mm)
Fig 22. This will help protect the mat when tiling. If you do not wish to use a levelling screed, you may tile directly over the mat in a single operation. Tile the floor using a flexible tile adhesive and grout as per industry standards and the manufacturer's instructions. Wait at least ONE WEEK before turning the heating system on to allow time to dry. If you are using a suitable vinyl or thin carpet as the final flooring, you will need to cover the mat with a suitable levelling screed - we recommend a minimum of a 6mm covering over the mat to ensure even heat distribution.

STEP 11

After the floor covering has been laid, test the Cable and Floor Probe one last time to ensure that neither have been damaged. Record final readings and complete the Guarantee Certificate as per the instructions on the certificate. If this is not done the Guarantee is invalid. Retain the certificate for your records.

DO – Read through these instructions carefully before beginning work
DO – Use flexible adhesives and grouts
DO – Test the cable mat and floor probe BEFORE tiling See steps 5, 8, 9 and 11
DO – Be careful not to damage or dislodge the cable during tiling
DO – Try to protect the cable mat with cardboard or carpet during tiling
DO – Wait at least 7 days before turning on the system
DO – Read the separate installation and operating instructions for the thermostat
DO – Ensure that the joint between the "Cold" Cable and "Heater" Cable is beneath the final floor covering.

DON’T – Attempt to cut the heater cable at any point
DON’T – Allow the wires to cross or touch
DON’T – Allow excessive foot traffic over the wire before tiling
DON’T – Cut tiles directly over the cable
DON’T – Place tools or stacks of tiles on top of the cable

Trouble shooting & FAQ’s

Q: When I perform the resistance test on the heating element I cannot get a reading?
A: Check that the test equipment you are using is on the correct setting and that the sensor probes are in contact with the conductors of the heating element.

Q: What should be used to house the thermostat?
A: Recommended depth 35mm, single gang socket box. Can be either surface or flush mounted.

Q: The heating element(s) is too large for the room, can they be cut?
A: Under no circumstances should the heating element be cut. If you find you have too much heating element, attempt to loose the excess cable in an adjacent area or use the clearance left at the edge of the room, maintaining a minimum of 50mm clearance between cables. Failing this contact the floor heating helpline.

Q: Can the elements be overlapped?
A: Under no circumstances should the heating cable/cable mat be overlapped or crossed.

Q: Can the heating system be installed onto a bitumen covered floor?
A: If there is only a thin residue of bitumen on the existing sub-floor, usually where the bitumen had previously been used to fix vinyl tiles or similar,

then you may lay the heating system down. If the bitumen covering has been used as a damp-proof membrane and is several millimeters thick, then this layer must be covered, either with a tile backer board or a levelling compound/screed, before the heating system can be laid.

Q: What type of levelling compound should be used?
A: Most floor levelling compounds that are available from tile suppliers will usually state on the packaging as to whether they are suitable for underfloor heating and are commonly referred to in the trade as “Latex”. The term latex refers to products that are a two part mix (bag of compound plus a bottle of latex). The two-part types are not as common today as the one-part, just add water, types which are fiber / polymer modified cement based screeds. The one part screeds are often sold under the banner of “Latex” and are much more readily available. Simply put, ensure what is used is either a genuine “Latex” 2-part or a 1-part fiber / polymer modified levelling screed. If you are in any doubt ask the supplier/manufacturer as to whether the product is suitable for underfloor heating

Q: What type of adhesive and grout should be used?
A: Any flexible tile adhesive and grout should be suitable. Most products will usually state on the packaging as to whether they are suitable for underfloor heating. If you are in any doubt ask the supplier/manufacturer.