Good morning LeeAnn, over coffee this morning Maryvonne started shooting some fire hazard and electrical safety questions at me. Since this is not our normal conversation fair since my retirement I thought this to be extremely unusual especially since we had lots to talk about.... e.g. the latest snowfall! Hopefully this note will provide some insite into using a waterbed heater as a small pond heat source.To keep the legal beagles at bay this is my personal comment and the writer accepts no liability of any form or fashion. I believe that you know my background so you can be the judge of the following statements .
Pete
The use of a water bed heater properly installed with an approved heater control designed for the pad can be used as a supplemental heating device if reasonable percautions are taken. It should be understood that the UL and CSA approvals are specific to the application and manufacture's installation instructions, any other use is technically not approved. Now that you are suitibly aware here is the skinny.
Water bed heaters depend on very fast heat transference from the pad to the water so it is important to have enough water mass ontop of the pad to made a good physical connection between the membrane (pond liner) and the pad as possible.Do not insulate between the pond liner and the heating pad. Most manufacturers recommend 8" of water on the pad before turning on the pad. It is important that you never place anything on the pad that provides point loading on the pad and excludes the water medium from the pad since it will create a hot spot and the resulting heat will cause premature failure of the pad. Do not place pots, bricks or supports directly on the pad, build support structure outboard of the pad always keeping the pad clear. A point worth mentioning is the capillary tube for the control, try to keep it 4" away from the heater and edges of your pond to keep the temperature constant. As with any pond or pool installation it is very important that the electrical system supplying it be suitable for the load and specifc application.
Please ensure that you have enough capacity, although these water garden loads are small they tend to add up and create all sorts of problems especially when you add lights and pumps. Anything that you connect that goes into your pond should be feed through a GFCI breaker to to eliminate / reduce electrocution hazards.
If you have any further questions PM Maryvonne.
Pete ( retired and inspired)
