Radiant Floor Heating Layout

Heating Capabilities

In many situations Warmup® underfloor heating can stand alone as the only heat source in the room. When using as a sole heat source, make sure that the room complies with insulation levels set out in current national and local building regulations as per the International Residential Building Code, chapter 11, and that the entire floor area is covered by the heating system.

If you wish to consider using Warmup as the sole heat source, you will need to seek assistance with a heat loss calculation from either an architect or HVAC specialist.

In rooms such as bathrooms and kitchens where there are objects that prevent you from covering the entire floor space, you may want to consider additional heating.

Heat Up Times

Heat-up times will depend on such variables as the thickness of the flooring and the design of the sub-floor however, here are some rough guidelines:

• Concrete with insulated tile-backer board - 3/8": 1 hour
• Un-insulated concrete slab: 2 - 8 hours
• Insulated concrete slab - insulation under screed: 2 - 5 hours

Economic to Run

Your Warmup® Underfloor Heating System`s power consumption - and therefore your running costs - relate directly to heat-up time. The longer the system takes to heat-up, the more it will cost to run. In a bathroom fitted with an insulation board on a concrete sub-floor, for example, heating 32 square feet of floor two hours twice a day would cost about $0.06* per day.

Running the same system on an un-insulated concrete sub-floor would cost about $0.12 per day.

* Estimate assumes that the floor heater will run 40-60 percent of the time once the room reaches the desired temperature.

Each case assumes a cost of $0.13 per kWh. These costs will vary from state to state, please check with your local power supplier for current unit costs in your area.

The graph below gives an idea as to the difference in running costs. It applies to a situation where the floor heaters are installed in a well insulated room and are required to heat the room for six hours a day.

The graph shows the running costs in cents per day on the left hand axis and the area to be heated in square foot on the bottom axis.

 

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Heater Layout and Multiple Heaters

You may wire a maximum of two USDW950`s through a Warmup® USTAT Thermostat with the floor heaters joining in parallel at the thermostat.

Make sure that the floor heating wire does not cross at any point and that the wire is spaced a minimum of 2" apart. Please refer to the sizing guide in the installation manual for additional information regarding spacing requirements.

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Areas in excess of 119 Square Feet (for 120VAC systems) or 239 Square Feet (for 240VAC systems:

The Warmup USTAT has a resistive load of 16 amps and may be used with both 120 and 240VAC systems.

If you want to control more than 16 amps worth of heating via a single thermostat (119 square feet for 120VAC and 239 square feet for 240VAC), you will need to use Warmup`s master thermostat & relay configuration. Instead of using the USTAT, a different model of master thermostat is used to control individual relay units (each capable of switching up to a 16 amp load, and each containing its own GCFI). The relays require their own separate electrical feed, and up to 10 relays can be daisy-chained to a single master unit via low voltage cabling.