Have a Tankless hot water heater? You should consider descaling the system. Each manufacturer recommends a different technique so it is best to look at you particular units manual before you do anything. You should be able to find instruction manuals for 99 percent of the tankless systems out there on this site (email me if your is not here).

Generally to preform the descaling process you would need to shut off the water and disconnect both the incoming and outgoing water pipes, also make sure to unplug the unit so that it doesnt fire and try to heat the cleaning agent. Then with a small pump push vinegar through the system and catch the fluid that comes out the opposite pipe. Personally we use a rubber hoses on both the input and out put pipes. The Rubber pipes are used so that two hose clamps can be used to trap the vinegar with in the system. Let the solution sit for about 20 minutes and then remove the clamps and turn the pump back on to flush out the buildup. Using the same pump flush the system with some pure water to clear out the cleaning solution. Simply reassemble everything and plug the unit back in and you will be back in business with a noticeable jump in heating efficiency.

Please read your systems manual before preforming this procedure, some units cant be flushed at all or it needs to be preformed by a specialist to retain warranty. If you have any doubts call your tankless manufacturer.

See Also:

1. The Tankless Hot Water Myth
2. What is a Tankless Water Heater?
3. Bosch Tankless Heater Review