As a rule of thumb, when you are heating an area over 130 sq ft, you will likely use a 240v system(s). Why?:
•120v systems provide more options for covering smaller areas; similarly, 240v systems provide more options for larger areas.
•As you will note on each flooring page, there is a product link where you can see the sizes available and their specifications which includes their respective volts and the amount of amps each size will draw. VIEW size options available.
•Whether you are using one or several heating systems, each specially designed thermostat that will power them can handle a load of 15 amps. Anything more than that and you will need to purchase an additional thermostat.
•The 240v products use less amperage which might help if you have limited space/breakers in your electrical panel.
•240v systems can also be used as a primary heating source. Therefore, if that is your goal, be sure to consider purchasing a 240v system.
The bottom line: The more heating systems and thermostats you need to purchase will affect the total cost. If you tried to heat a large area with 120v systems, you would need more material and therefore more thermostats to power them. However, this voltage but would be ideal for smaller areas.
1.2 What do I need to prepare for my project?
Before you order your heating system, there are a several things you can do in preparation:
• Draw a floor plan. It doesn’t have to be pretty or complicated. This step will allow you to visualize what you are trying to accomplish and will help you make a decision as to whether a loose wire or mat floor heating system will work best. Check out our design guide for some installations ideas. It will be important to make note of where you want to locate your thermostat since this will be the starting point for all of your heating systems.
• Measure the area that will be heated. When writing down your measurements, keep in mind that you will not be heating areas under permanent fixtures such as cabinets, bathtubs and toilets. To determine the square footage of your actual heated area, you will subtract the square footage of those areas from the total amount. When taking your measurements, factor in a 4” border from any walls and permanent fixtures. This information will help determine what size product(s) you will need. Please note that it is important that you note that the measurements for your project must only be for heated square feet. Measuring any other way will overestimate the amount of product needed and since the wire CANNOT be cut, this will result in a return of the product (which will delay your project) or a lengthier installation which will require a reconfiguration of how the product is installed, causing more labor time.
• Make sure your electrical panel will be able to handle additional amperage requirements. Each thermostat used to control your heating system will require 15amps. We recommend that you place your floor heating system on its own dedicated circuit. Check the main breaker in your electrical panel to see how many amps have been installed for your home. If there is no more room in your existing panel you can have a licensed electrician install a sub-panel. We suggest a 20A dedicated line for each Warmup system installed.
•Consider insulating your floor. While you can install your floor heating system directly over a concrete sub-floor, it is not advised. The concrete will absorb the heat first, before allowing it to rise to your tile, thus not allowing the product to be as energy efficient as it could be. A floor that could have heated up in minutes will now take hours. Warmup Insulation Boards have been specially designed to allow for a thermal break. In other words, they radiate the heat upwards into your floor instead of into your sub-floor. The insulation boards are 2’ x 4’ and ¼” thick and will be installed throughout the room you will be heating.
The bottom line: Be sure that when you put in a request for products or for an order, you have measured the area that will be heated, excluding any permanent fixtures. If you have a floor plan and need assistance, please submit it via email (email@example.com) or fax (888-927-4721) so a representative can assist you with finding the best product for your project. Please be sure you include all necessary contact information (name, email address, phone number, location, etc.) so we can provide the best information possible.CLICK HERE to fill out our contact form.
1.3 Basic Installation
The Warmup® In-slab Heating Cable is designed to be placed within the cementitious slab of at least 2” (50mm) in thickness, with at least 1¹/₈” (30mm) of slab above the heating wire. Depending on the construction of the subfloor, you may need to use additional insulation with your installation. REMEMBER TO TEST THE RESISTANCE OF THE CABLE BEFORE, DURING AND AFTER INSTALLATION.
Step 1: Prepare floor plan of the area requiring the slab heating system & note the area to be heated. It is advised that a floor plan is drawn up to determine the placement of the thermostat, heating cable and the sensor probe. This diagram should be kept for future reference.
Step 2: The fixing strips should be laid out perpendicular to the heating cable runs. These fixing strips must be secured to the insulation or the concrete floor using fixing nails or an adhesive. It is important to ensure there is no movement of the fixings.
Step 3: The fixing strips should be evenly spread across the floor at interval of 30” (0.75m). The fixing strips should be placed so as to leave a minimum of 4” (100mm) border all the way around the room.
Step 4: Examine the cable and test the resistance BEFORE, DURING and AFTER installation. Unfamiliar with how to use a digital multi-meter to obtain your resistance figures? CLICK HERE for instructions.
Step 5: The heating cable should then be laid up and down the room and clipped into the fixing strip. The cable spacing is determined by the product model. The cables should be spaced evenly at all times to ensure an evenly heated floor (minimum spacing is 2” (50mm). The cables should never touch or cross each other.
Step 6: The heating cable cold tail should be connected to the thermostat by a qualified electrician in accordance with NEC (USA). The heating cables should then be tested again BEFORE POURING the layer of cement. Record the readings in the notes section. Once laid, the heating cables must be covered with a minimum thickness of 1¹/₈” (30mm) of cement.
NOTE on installation on Reinforcement Bars:
Warmup In-Slab Cables are suitable for attaching to the reinforcing steel bars in concrete from a depth of, 1.5” to 3.0” below the surface. Only one cold tail at one end exists, simplifying the installation. The heating cable must not be cut or shortened and must be GFCI protected. Once the on-center-spacing (OC) has been worked out the cables can be tied to the re-bars using plastic cable ties. Care must be taken not to tighten the ties too much, causing damage to the cable. Any number of ties can be used ensuring that the on-center-spacing is maintained. For ease of installation, cable lengths can be determined to match the rebar spacing. For an 8” rebar spacing (200mm), measure the area to be heated in sq ft, multiply this by 12 and then divide by 8”. This gives you the length of cable in feet.
1.4 How to Troubleshoot Your In-Slab Cable System
NOTE: All power to the units should be shut off at the breaker panel before checking any electrical connections.
•Is the heating system wired correctly? Have a licensed electrician check to make sure that the heating system is correctly connected to the thermostat and the thermostat to the electrical panel. Instructions for wiring came with the heating system and thermostat but can also be viewed online at www.warmup.com.
•Confirm there is enough power being supplied to operate your heating system. Warmup recommends that your floor heating system be placed on a dedicated circuit to power your heating system. Verify that the circuit can handle the amount of amperage your heating system requires. Contact your reseller/installer for details regarding your particular configuration.
•Check the resistance readings of your heating wires. To ensure that your floor heating system will function properly, always test the resistance of your wires with a digital multi-meter before, during and after installation prior to covering in thin-set or floor leveler. Use the information contained in pages 6 & 16 of the installation manual for details. If at any point during one of your tests the results do not match up with the numbers your Warmup manual indicates you should have, this indicates you have a short or a break in your wires. Warmup can provide your installer with the tools needed to perform a repair when possible.
•Was your heating system installed directly over a concrete sub-floor? If you installed your heating system over a concrete sub-floor and did not first install Warmup Insulation Boards, it could take over an hour for the floor to heat up since the sub-floor receives the heat first and the flooring second. In this instance you simply need to allow for more time.
•Make sure that the floor probe that came with the thermostat was installed and done so properly. Make sure that the probe is installed underneath the mat and evenly placed between a run, never to touch or cross. Installation procedures and thermostat settings can be reviewed in the installation manual and user guides that were provided, and can also be accessed on our website at www.warmup.com.
NEVER turn on your floor heating system unless it has been completely encapsulated in thinset or floor leveler and these compounds have had an opportunity to completely cure (at least 1 week) as directed in the installation manual that you received with your product. If you ignored this warning and activated your heating system without the wires being covered, you likely overheated them and will need replacements.
1.5 Using a TDR Meter To Locate Shorts Or Breaks In the Wire