Freeze Protection Systems For Condensate Pipes
Automated freeze protection systems for condensate pipes offer a cost effective way to prevent pipes freezing up in the winter. By suitably protecting a pipe you can avoid the associated boiler shut-downs that often happen and you avoid incurring the high costs for an emergency call out from a plumber to rectify the problem. The cost of purchasing and installing a freeze protection system like condensate pipes is remarkably low; usually significantly less than the call out cost of a single emergency plumbers visit. The running costs of the system are also economic; however the actual cost for operating a system will depend on the insulation placed over it and the weather conditions where the condensate pipes are fitted. The thermostat attached to the freeze protection unit switches the system on when the temperature falls to 3oC, and heats the pipe to around 15oC before switching off again (which would normally take no more than 10 minutes). As long as the condensate pipe and heater are sufficiently insulated the heater will not need to turn on again for a significant period of time as it will take a long time to cool back down to 3oC. In temperatures down to 0oC, the system will need to operate roughly 10% of the time, and once temperatures fall below 0oC the system will need to supply heat for around 20% of the time, as a very rough guide. Two examples are provided below: At Shoreham-By-Sea, on the south coast of England, there have been an average of 877 hours per year when the temperature has fallen to 3oC or below, with 254 hours on average with temperatures below 0oC. These figures are based on data from the last 10 years. With these temperatures and the assumptions above the system would have used 1.6kW of electricity per year per meter, at a cost of around 20p per annum. At the top of Great Dun Fell, the second highest peak in the Pennine range, there have been an average of 3,313 hours per year when the temperature has fallen to 3oC or below, with 1,727 hours on average with temperatures below 0oC. These figures are also based on data from the last 10 years. With these temperatures and the assumptions above the system would have used 7.1kW of electricity per year per meter, at a cost of around 85p per annum, although these are extreme conditions. 
The pricing below is based on the assumptions above, but assuming that an 'average' cost for running a system is roughly 46p per meter per year (as can be seen from the map on the right, most of the UK sits somewhere between these two highlighted areas). The costs for protecting various lengths of condensate pipe would be as follows: 1.4m £0.644 per annum 2.0m £0.920 per annum 4.0m £1.840 per annum 8.0m £3.680 per annum