Unlike traditional non-condensing models, condensing technology captures heat from the exhaust gas and uses it to preheat the incoming cold water. This increases efficiency and reduces emissions -- well ahead of the 2012 Low NOX emissions standards set by SCAQMD (California -- South Coast Air Quality Management District).
The Bosch C800ES features an electronic ignition system and can vent through either 3 inch or 4 inch diameter PVC vent pipe either through the side wall or up through the roof. A 3" PVC concentric vent kit is available for venting vertical or horizontal and allows the unit to be vented and also have its intake air from the outside through one hole.
The Bosch C800ES does not come with the built-in Freeze Protection kit but it is available as an accessory. The C800ES also does not come with an external water filter screen but is also available as an accessory. The Bosch C800ES does come with a standard 3/4" PRV. The Bosch Therm C 1050 ES tankless water heater is about the same as the C800ES except that it comes with the freeze protection kit. The Bosch Integra 500 is also about the same as the C800ES and the C1050ES and it comes with the freeze protection, 3/4" PRV and the external water filter screen. All three tankless heaters are 199,000 BTUs and have the same temperture rise.
The freeze prevention kit is designed to provide protection for the water heater down to approximately 5°F for short term conditions only. It will not protect the appliance in areas where the temperature is routinely expected to be below freezing. The freeze prevention kit will not protect plumbing outside the appliance from freezing.
The Bosch C800ES comes with a limited 15 year warranty on the heat exchanger and 5 years on all other parts. Service and labor costs are not covered.
