Whether you need a UPS for a gas boiler, what are the different types and how to choose one

Modern gas boilers are good in that under normal conditions they operate fully autonomously. For stable operation they need a certain gas pressure and a constant power supply. With this task will cope uninterruptible power supply for gas boiler. What are the parameters of these devices and how to choose read in the article.

Why do you need a UPS

In our country in winter time without heating can not do without heating. And heating is desirable without failures and stops – in severe frosts possible defrosting of the system. When organizing the system must remember that most of the modern boilers are controlled by automation, and the movement of coolant in the system is provided by circulation pumps. All this equipment is powered by electricity.

Given that in wintertime power outages are not uncommon, it is necessary to take additional measures to create a redundant power supply. In most cases, a UPS – uninterruptible power supply – is used. Its task – to supply power from rechargeable batteries in case of loss or “sagging” voltage in the network.

Features of the choice for gas boilers

Uninterruptible power supply is selected with such a condition that it gives out a voltage of a given value, the correct form, as close as possible to the sinusoid.

This is necessary to ensure the normal operation of the control unit. In most imported gas boilers automation is assembled on electronics, and it is demanding to the quality of power supply. To assess how important this requirement is, it is worth saying that according to the statistics of service centers about 40-55% of breakdowns of gas boilers are associated with the failure of the control board. Often the boards are not repairable and must be replaced.

It is also worth remembering that the failure of the control board due to unstable power supply – the case is not guaranteed in all manufacturers. So the cost of the board and its replacement has to be paid from your own pocket. If you also remember that the cost of the board – this is about 40-50% of the cost of the unit, willy-nilly think about buying a quality and reliable UPS for gas boiler.

The good news is that a single UPS of sufficient power can be connected to a variety of equipment that requires quality power for its uninterrupted operation. Most commonly these are computers, televisions and a couple of emergency light bulbs.

Types of uninterruptible power supplies

Today, the trade network offers UPS of three types:

• Off-line (online).
• On-line (off-line).
• Line-Interactive (line-interactive).

Ofline UPS (standby type).

This is the simplest and cheapest sources of uninterruptible power supply. Off-line from English can be translated as “not in line”, which reflects the principle of operation of this device. In the uninterruptible power supply of this type is set the upper and lower limit of voltage, the normal operation of the boiler. As long as the parameters of the network are within these limits, power is supplied from the power grid.

If the voltage becomes higher or lower, the switching relay is activated, the power is supplied through the UPS from the batteries. When the mains parameters return to normal, the relay is triggered again, disconnecting the uninterruptible power supply. For a gas boiler such protection, of course, is better than nothing, but during switching on/off in the network there are significant voltage spikes. So stabilization in this case is not complete – there are no large dips or peaks, but the supply voltage is not ideal. The second disadvantage of off-line type uninterruptors – they can not correct the shape of the sinusoid.

Such power supplies should be used only if a stabilizer is installed. This scheme is expensive, but creates normal conditions for the operation of equipment that is demanding to the quality of power supply.

On-line UPS (constant type)

This type is also called uninterruptible power supply units with double conversion. All because of the principle of operation:

• The AC voltage coming into the input is converted to DC voltage and is used to charge the batteries connected to the device.
• The DC voltage is converted into AC voltage with a perfectly shaped sinusoid.

The power supply is converted twice. This guarantees voltage stabilization and a perfect sine wave.

Such uninterruptible power supplies are connected to the power supply circuit. As long as the voltage is normal, the line power is converted. When the voltage is low, the shortage is made up for by charging the batteries, and in the absence – the power supply is supplied from the battery.

The disadvantage of this equipment is the high price and rapid discharge of batteries. Nevertheless, if you need the best uninterruptor for the boiler – buy equipment online type.

Line-Interactive (line-interactive)

Properties and characteristics of uninterruptors of this type, not as good as online models, but not as bad as offline units. There are all the same rechargeable batteries and a switch that, when the voltage drops, connects the UPS. But for voltage stabilization there is a special unit – an automatic voltage regulator (AVR in the picture above).

The disadvantage of linear-interactive uninterruptible power supply sources for a gas boiler – non-momentary switching when the voltage changes. But it is much smaller than in offline devices, but the voltage is kept constant (within certain limits). This equipment is the optimal choice, because at a relatively small price guarantees good results.

Determining the parameters of the UPS

The disadvantage of line-interactive UPS is not instantaneous switching when the voltage changes. But it is much smaller than in offline devices, but the voltage is kept constant, within certain limits. This equipment – the optimal choice, because at a relatively small price guarantees good results.

How to determine the power of the uninterruptible power supply

To determine with what power you need a power source, look for the line “power consumption” in the passport of the gas boiler. On average, it is 150-170 W. If there is a second circulation pump in the system, its power consumption should be added to this figure.

In order for everything to work without problems, you need a power reserve of at least 20-30%. If possible, when choosing a UPS, the result can be doubled – just in case. Sooner or later you will want to add a couple of devices to the load, because it is really convenient – when you have at least something working in the absence of electricity.

Determine the capacity of the battery

Many models of uninterruptible power supplies have built-in batteries. In this case, you do not need to count anything. If the batteries are connected separately, you need to find in the technical characteristics of the line “maximum charge current”. This figure is multiplied by 10, we get the capacity of the batteries that can charge this UPS. It is possible to connect larger batteries, but in this case they will not be fully charged, which reduces their service life.

So how to choose a UPS with built-in batteries? By the amount of battery life you need. Dependence of operation time on battery capacity and power consumption is shown in the table. It is not difficult to select a power supply for the boiler.

Criteria for selecting a UPS for a gas boiler

From all this we can deduce the following requirements for the uninterruptible power supply:

• Special UPS with an output voltage in the form of a sine wave is necessary. UPS for computers are not suitable. They do not output a sine wave, but an approximated or modified sine – the voltage is also variable, but the sine wave looks like a stepped. For computers, such a voltage is not a problem, but it is not suitable for circulating pumps, they hum, work jerkily.

  

• The power of the UPS is selected with a reserve. If possible, it is necessary to double the consumed power.
• It is desirable to choose the type online, not a bad option – interactive type.
• The capacity of the batteries should be selected so that in the event of a power failure, the heating can work for several hours at least. This requirement is not critical if there is a generator. By the way, this is another reason why you should not put computer uninterruptors for the boiler – it is designed to operate the equipment for 10-15 minutes. During this time, you can correctly complete the work of all programs and turn off the equipment. For the boiler these minutes are too short time.
• It is desirable that there was an opportunity to connect additional external batteries. This will come in handy if you decide to increase the time of heating operation from a backup power source or to connect other equipment.

  

The requirements are not the most stringent, but it is desirable to adhere to them. When connecting the uninterruptible power supply, observe the phasing. The phase of the UPS must be connected to the boiler phase, the zero and minus must be connected to the respective conductors. Otherwise, this may result in a short circuit. To check the phase lead, purchase a test lead.

Checking the boiler is simple: pull the boiler plug out of the mains. The boiler should continue to work. If the flame goes out – check the correctness of the connection, earthing. If everything is normal, but the boiler still does not work, then your UPS is built without “through zero”. To start the boiler, you need to connect the neutral N (zero) terminals at the input and output on the UPS. For most boilers, this rewiring solves the problem. But there are some brands of boilers, for example: Buderus (Buderus), which need between the inputs PE and N (ground and zero) set a resistance rated from 1 to 10 megohms.

Actually, this is all about choosing and even connecting an uninterruptible power supply for a gas boiler.