Backup power supplies for circulators are important accessories for "backing up" the boiler or fireplace and other heating equipment. It is used to keep the equipment in operation in the event of a short-term or long-term power blackout. Backup batteries protect the boiler from overheating and thus from consequential material damage. Of course, they also ensure your safety!
For longer blackouts, which are in the matter of hours, you need to drain the hot water from the boiler - especially for solid boiler fuels. In this case, solid fuel (coal, wood) burns inside the boiler and it is necessary to drain hot water for several hours to prevent the boiler from overheating. One of the effective properties of backup power supplies for circulator pumps is also the compensation of voltage fluctuations in the network.
Backup power supplies for pumps are also suitable when the mains is switched off for a long time, but you need to heat domestic water (DHW) connected to solar heating. Backup power supplies can keep appliances running.
There are two types of backup sources (depending on the connection) - sinusoidal, which are usually better and more efficient, and can be connected to any device which you then plug into a standard socket. Trapezoidal backup power supplies are a cheaper option, but have limited possibilities of use. These batteries try to mimic the sinusoidal course of alternating current. Such a course may resemble a bar graph rather than a sinusoidal waveform. Some appliances may have a problem working with a very "rough" course. Characteristics of backup supplies are a broad topic in the field of electrical engineering.
It must be selected according to the required backup time and the appliance. The capacity of batteries differ, which is the time they will keep the pump running. It is given in ampere hours (Ah). You also need to know the power input of your circulators. Knowing the capacity (Ah) and the pump power input in kilowatt hours (kW), it is then easy to calculate the duration your device will run on the backup power supply battery.
For example, the duration is about an hour when consuming 120 W. Manufacturers usually state this figure for normal operation, so the actual time may vary. If you are interested in a specific product, you should also focus on battery life. Over time, the battery must be replaced, depending on the use of the backup power supply. Bear in mind that even when not in use, the battery deteriorate and its service life decreases.
We recommend for example a backup power supply Integra Tech Heat Master F200, which has fully automatic operation. It is suitable for circulator pumps and boilers regardless of type or manufacturer. The Wilo PG 500 Compact backup power supply has two built-in maintenance-free 12V 9Ah batteries. Battery life is approximately 5 years.