Minimum power values
This is the second criterion that deserves close attention (after choosing a standard or inverter version) when you need to buy a generator.
Determining its power is easy. For this, the starting and functional power of all connected devices is added up. A reserve of 20-30% is added to the result.
The minimum power for the operation of the boiler is reflected in its documents. There are also indicators of electricity consumption and power consumption. As a rule, these are parameters in the range of 120-180 watts. Approximately 150 W is required for the circulation pump and the turbine, if it is installed in the boiler.
Calculation example:
One boiler is connected to the generator. Then, for full-fledged work, a minimum of 0.5 - 0.62 watts is required. This is the result of such arithmetic: 120-180 + 150 + 150 + 20-30%. It turns out 504-624 watts.
Today, buyers have the opportunity to purchase devices with parameters of 0.6 - 7 kW. In 90% of situations, this is enough for devices that produce 0.8 - 1 kW. In other cases, the total power of all equipment connected to the generator is calculated.
Model examples
There are plenty of brands of boilers. And often users wonder about the selection of a generator for a boiler of a particular brand.
The following are examples of certain models of boilers and the most suitable modifications of gasoline generators.
First: Boiler - Baksi Ecofor 24.
Suitable Generators:
- Hitachi E50. The price tag is 44 thousand rubles. Power - 4.2 kW.
- Huter DY2500L. Cost - 18 thousand rubles. Power - 2 kW.
Second: Cauldron - Vailant 240/3.
He needs a high-quality stabilizer, such as Resanta ASN-1500, especially if the electricity is turned off every 4-5 hours.
Suitable alternator is Hyundai HHY 3000FE. It has an integrated AVR, modest fuel consumption and a power of 2.8 kW. It starts with a key and cable. Price tag - 42,000 rubles.
Third: Bosch Gaz 6000w. It does not depend on the phase and is supplemented with a stabilizer Stihl 500I for high-quality work.
For complete stability and safety, a SWATT PG7500 generator with a power of 6 - 6.5 kW is attached to it. Cost - 40200 rubles. It can work without interruption for 8 hours. Equipped with ARN.
Fourth: wall model Buderus Logamax U072-24K. This is a powerful double-circuit modification with automatic electric ignition.
An inverter generator is required. For example, Enersol SG 3 with a power of 7-8 kW. It costs about 60,600 rubles.
Fifth: boiler Proterm 30 KLOM. This is a phase dependent floor model.
It is usually used together with the stabilizer type "Calm" R 250T. A suitable generator option is Elitech BES 5000 E. It costs about 58,300 rubles. Power - 4-5 kW.
The sixth is the Navien Ice Turbo device - 10-30 kW.
With it, it is optimal to use the ABP 4.2-230 Vx-BG generator with a power of 4 kW and an average price tag of 55 thousand rubles.
If reliable fuel supply is required in field conditions or in the country, when there is no electricity, then it is optimal to use a generator that produces a pure sine wave, Huter HT 950A.
This is a convenient compact petrol model with low fuel consumption. It is able to work continuously for 6-8 hours if it is fully charged.
The engine here has one cylinder and two strokes. This is a guarantee of smooth and stable operation of the entire generator.
Other advantages:
- The tank cap is located so that it is convenient to control the fuel level and refuel.
- Overload protection available.
- Low noise levels.
- Special indicators allow you to monitor the oil level and control dangerous situations.
- Replaceable air filter and muffler.
- The engine is reliably protected from external influences by a shock-resistant housing.
- There is an exhaust pipe that removes gases. Therefore, the device is only used outdoors or indoors with powerful ventilation.
- To use the device does not require special skills and knowledge.
- Modest price - 6100 rubles.
Selection and calculation of the inverter
When calculating the required output power of the inverter, it must be taken into account that the presence of circulation pumps in the load circuit of the electric motors will cause an increase in both the constant current consumption, which determines the so-called power factor of the electric motor (cosine phi), and a significant current load at the time of starting the pumps. The maximum power consumption should not be more than 75% of the maximum power of the inverter output stage, especially for line-interactive devices in which the inverter operates continuously.
For example, let's take a system consisting of a Baxi Fourtech gas boiler and two Oasis 25/2 pumps. Since the boiler electronics itself does not have an inductive load component, its rated electric power of 130 W will be taken into account without correction. The pumps have a rated power of 35W. If the manufacturer did not also indicate the power consumption (in this case, 60 W), it could be defined as two times the nominal one. Consequently, the consumption of two pumps will be 120 W in steady state, setting a double margin for starting current and summing it with the consumption of the boiler itself, we get a figure of 370 watts. Taking into account the power reserve for the output stage of the inverter, we need a converter with a power of at least 0.5 kW.
If the inverter manufacturer specifies its power in kilovolt-amperes (kVA), you can convert it to kilowatts by knowing the power factor (cos φ) of the inverter itself. So, an uninterruptible power supply with cos φ = 0.8 and a power of 1 kVA has a real power of 800 watts.
The second parameter when choosing an uninterruptible power supply is the time during which it can provide power to the intended load. When calculating it, it should be taken into account that, on average, the operability of the UPS output converter is maintained when no more than 75% of the battery capacity is depleted. For example, if we use a battery with a capacity of 60 Ah, in reality it can give no more than 45. Further, taking into account the average inverter efficiency of 80%, we get the following:
- The load from the previous example in steady state is 250 W, taking into account the losses in the inverter, we get a power taken from the battery of 312 W.
- At a nominal voltage of 12 V, this power means a current consumption of 26 A - a fully charged battery will be able to provide the load for approximately 1.7 hours.
The type of uninterruptible power supply you choose determines both the budget and the features of the electrical network used. With relative stability of the voltage in the network, it is enough to purchase an “offline” class UPS, but if the voltage fluctuates a lot, it would be more reasonable to either supplement it with an external stabilizer, or immediately buy an “online” or line-interactive inverter. Since inverters of the required power usually use external batteries, it is worth clarifying what maximum charging current they can provide.
Considering that the optimal current for charging the battery is 10% of its nominal capacity, a device with a declared charging current of 6 A will work with batteries up to 60 amp-hours.
Other criteria
Having resolved the issues with the main technical points, pay attention to the following:
- Duration of work without pauses. Ordinary household models are not able to work 24/7. After all, their engine needs breaks for cooling. More massive and powerful units withstand from 12 to 16 hours. Compact versions, weighing less than 10 kg, work without rest for 3-5 hours.
- Launch method. There are only two options: manual and automatic. The second guarantees complete autonomy of the heating network. But only expensive and powerful devices have this option.
- Noise indicators. They are due to the functional speed of the engine, the ability to control them and the presence of sound insulation. Almost all low power generators have a special casing that isolates the sound.
Synchronous and asynchronous system
To make the right choice, you should know their distinctive characteristics.They are set out in the following table:
Characteristics Synchronous Asynchronous Voltage and frequency Stable and high-precision holding Variation in a significant spectrum Electrical overloads High vulnerability to them when starting in standard mode. Resistance to them in starting in a similar mode.
Synchronous models are purchased when a scrupulously accurate current value is required, and the voltage in the network often changes over a wide range.
Devices of the second category are a good budget option and protect the heating network from power surges. This is especially true in domestic conditions. But for this, it is recommended to supplement the devices with uninterruptible power supplies (IBS).
Why does the boiler go out when the light is turned off
In the event of power outages or breakdowns in the electrical network, the boiler automation is unable to perform its functions and immediately turns off the burner. This is ensured by the very design of the gas valve: it is pressed by the current passing through the coil.
If there is no current, it closes immediately.
Power outages, unfortunately, are not uncommon for Russia. So the owners of the boilers have to sit in a cold house, although gas may be present in the line. It cannot be ignited without electricity, and interference with the boiler device can lead to a fine from the technical supervision authorities, as it leads to violations of fire safety.
Choosing a heating boiler for the home
Today, the modern market offers a wide variety of boilers from foreign and domestic manufacturers. How to make the right choice and not make a mistake? Do not miscalculate the cost of a heating boiler for your home? You can, of course, entrust the choice of a boiler for heating a house to a qualified specialist if he designs a hot water supply and heating system. He will be able to provide the best combination of elements of the system, tell you which boiler to choose and how to obtain the permits required for its installation. But it is quite possible to sort out the priorities yourself when choosing a boiler, which can economically heat the house.
For any home, communications are the most important: plumbing, power wiring, heating and sewerage. The quality of heating has a direct impact on how comfortable a home is and how expensive it will be to maintain, especially during the heating period.
Choosing a generator for the boiler
For a gas boiler with an electronic control unit, it is preferable to purchase an inverter gas generator. Its price is noticeably higher than a simple one: 20-40 thousand rubles. against 5-7 thousand, but it provides sinusoidal voltage waveform and stable frequency and voltage. In the inverter generator, an unpretentious input rectifier and filter feed the inverter - a DC-to-AC converter with excellent quality.
Before buying a generator, you need to find out what kind of power the boiler and pumps, if any, require. In the simplest case, it is enough connect the terminals of the gas generator to the plug power supply to the boiler and start the generator engine. Then you can fire up the boiler in the usual way.
When electricity appears, the generator can be turned off and switched to the mains.
If the pumps in the system have three-phase motors, then the generator inverter must also be three-phase, and the boiler automation will be powered by one of the inverter phases. This applies to sufficiently powerful heating systems that heat medium-sized buildings and large cottages. Such a system should provide for uninterrupted power supply to boiler automation and pumps from an inverter that works together with the mains, through a bypass or even online. The generator is started in such systems to avoid too long discharge of the batteries.
The power of the purchased generator should be selected with a 30-50% margin of the power consumed by the boiler together with the pumps. This will reduce the load on the generator motor and ensure its longevity.
If the boiler can be powered by a gas generator, but has a separate neutral and phase, that is, it is not connected with a plug to a socket, but is mounted with a cable into a switchboard, then a special generator connection scheme will be required, which excludes the simultaneous operation of the network and generator. A single-phase inverter generator can be connected to such a boiler in any way, i.e. both its terminals are equal in this case. RCD with this connection should work.
The table shows examples of some 220 V gas generators.
| Model | Power | Reliability | Noise | Price | Weight | launch | Fuel consumption | Working hours | Service | Reviews |
|---|---|---|---|---|---|---|---|---|---|---|
| DDE GG950DC | 625 W | 4 | 65 dB | 4400 rub. | 18.5 kg | manual | 0.72 l | 5.8 h | — | good |
| DENZEL DB950 | 650 W | 5 | 62 dB | 4800 rub. | 17 kg | manual | 0.7 l | 5 h | — | great |
| FAVORITE PG950 | 950 W | 4 | — | 4990 rub. | 16 kg | manual | — | — | — | — |
| Most Power G800L | 650 watts | 4 | quiet | 5027 rub. | 17 kg | manual | 0.69 l | 4 h | there is | good |
| CHAMPION GG951DC | 650 W inverter | 4 | very quiet | 5250 rub. | 19 kg | manual | 0.65 l | 4.6 h | there is | great |
| Hammer GNR800B | 600 W | 5 | quiet | 5990 rub. | 18 kg | manual | — | 8 h | there is | great reviews |
| DDE DPG1201i | 1 kW inverter | 4 | 58 dB | 6490 rub. | 12 kg | manual | — | 4.5 h | — | good |
| DDE DPG1201i | 1 kW inverter | 4 | 65 dB | 6610 rub. | 13 kg | manual | — | 5 h | — | normal |
| Eurolux G1200A | 1 kW | 4 | 75 dB | 6680 rub. | — | manual | 0.58 l | 9 h | there is | very stable |
| Caliber BEG-900I | 900 W inverter | 4 | 70 dB | 6590 rub. | 12 kg | manual | 0.52 l | 8 h | there is | works well, lightweight |
| Redbo PT2500 | 2.2 kW | 5 | — | 6990 rub. | 38 kg | manual | — | 14 h | — | — |
| Eurolux G3600A | 2.5 kW | 5 | 77 dB | 9002 rub. | — | manual | 0.8 l | 18 h | there is | great |
| FAVORITE PG3000 | 2.5 kW inverter | 5 | — | 9620 rub. | 36 kg | manual | — | 13 h | there is | great |
| Kolner KGEG 5500 | 5.5 kW inverter | 4 | 72 dB | 20493 rub. | 78 kg | manual | 1.6 l | 12 h | there is | good |
| CHAMPION GG650 | 5 kW | 5 | — | 22100 rub. | 77 kg | manual, starter | — | 13 h | there is | very reliable |
| Bort BBG-6500 | 5.5 kW inverter | 5 | 75 dB | 20750 rub. | 77 kg | manual, starter | 1.8 l | 12 h | there is | good |
| Daewoo Power Products GDA 12500E-3 | 10 kW, inverter, 220/380 V, 3 phases | 4 | — | 159000 rub. | 165 kg | manual, starter, auto start | 4.2 l | 5 h | there is | good |
| ENERGO EB 15.0/400-SLE | 12.6 kW, 220/380 V, 3 phase | 4 | 75 dB | 227700 rub. | 135 kg | starter, autostart (AVR) | 4 l | 6.2 h | there is | — |
| EUROPOWER EP16000TE (Honda) | 13 kW | 5 | 77 dB | 293791 rub. | 152 kg | starter, autostart | 5.1 l | 4 h | there is | good power plant |
| ENERGO EB 14.0/230-SLE | 11 kW, 220 V, 1 phase | 4 | 74 dB, with acoustic cover | 554480 rub. | 930 kg | starter, autostart | 3.9 l | 6 h | there is | — |
Connecting a gasoline generator
In this process, first of all, it must be taken into account that the device runs on fuel. And after burning it should come out. For this, an extract is created.
There should be free space around the device itself: 1-2 m. This is to provide access to the device for various purposes: refueling, manual start or repair.
Before connecting the unit to the boiler, read the instructions. To connect to the network, a switchboard is used, in which an automatic fuse is arranged.
Both devices must be grounded. You can act according to the standard scheme:
So you guarantee safety and the appearance of zero. These are mandatory conditions, without which the system will not be able to identify the flame, and the boiler will not start.
If the generator is installed for the whole house, then a common network is used to ground it.
In order for both units to function correctly, the output must have a sinusoid of 50 Hz. With other indicators, the boiler will start problematic. IBS can correct the situation.
In general, the algorithm for connecting the generator to the boiler has the following steps:
- Search for the necessary contacts in both devices (the diagram in the instructions helps with this).
- Connecting and insulating wires.
- Grounding of devices.
These operations look simple, well, it is better to trust them to professionals.
UPS installation rules for a gas boiler
Do not place the UPS near the cold water supply pipes of double-circuit boilers (condensation forms on them), as well as near the heating pipes, so as not to impair the cooling efficiency of the inverter. Batteries should also not be exposed to low or excessively high temperatures.
Do not use the UPS in conjunction with lead-acid batteries, unless it is directly indicated in the instruction manual for this uninterruptible power supply. The difference in charge current characteristics between lead acid and gel batteries may cause the UPS charger to malfunction.
It is advisable to use offline class devices in conjunction with a voltage stabilizer connected between them and the external network.
When used in the heating system of a phase-dependent gas boiler in conjunction with a UPS, its output is connected to the load through an isolating transformer. This is due to the fact that when the inverter is running, both of its outputs are phases with respect to ground, while a phase-dependent boiler requires a well-defined phase and neutral supply. For this, an isolation transformer is used, one of the terminals of the secondary winding of which is grounded.
pivot table
In the following table, you can get acquainted with 9 popular and efficient UPSs on the market, which are divided into 3 subgroups. From the names, you can understand that the main factor is the necessary uptime.
We also took into account the heated area of the house: the larger it is, the higher the power consumption of the boiler and pumps. Each subgroup includes models for houses up to 100 sq.m (power consumption of boilers and pumps - 100-150 and 30-50 W) and for 100-200 sq.m. (150-200 and 60-100 W).
| Group 1: UPS for short (up to 2 hours) and rare (2-4 times a year) outages | ||
|---|---|---|
| 1. |
Ideal for: a boiler in a small house up to 100 sq.m with a stable mains voltage of 220 V |
11000₽ |
| 2. |
Ideal for: boilers without external circulation pumps in a small house up to 100 sqm |
10800₽ |
| 3. |
Ideal for: connection of boilers and pumps in houses 100-200 sq.m. |
12900₽ |
| Group 2: UPS for long (from 2 hours) and frequent (from 5 times a year) outages | ||
| 4. |
Ideal for: sensitive boilers and pumps in 100-200 sqm houses with unstable voltage |
16800₽ |
| 5. |
Ideal for: boilers and pumps in houses 100-200 sq.m with stable voltage |
12900₽ |
| 6. |
Ideal for: Boilers with built-in pump in houses up to 100 sqm |
10325₽ |
| UPS to work together with an electricity generator | ||
| 7. |
Ideal for: uninterrupted power supply of boilers and pumps with unstable voltage |
19350₽ |
| 8. |
Ideal for: Boilers with extra low voltage and high noise requirements |
17700₽ |
| 9. |
Ideal for: Expensive boilers with sensitive electronics |
21600₽ |
And now let's take a better look at the characteristics of the models, study customer reviews and watch video reviews.
Types of uninterruptible devices
By design, uninterruptible power supplies are divided into three types:
Online inverters for the boiler, unlike offline ones, have a built-in stabilizer at the input and, due to this, they switch to backup power from the battery only when the power is turned off in the network. When its voltage deviates from 220 V, the stabilizer works. This scheme is more expensive, but also more efficient when used in a network with a strong diurnal voltage float (for example, a low-power substation in the private sector). An offline inverter under such conditions will go into standby mode too often, requiring a separate voltage regulator to be installed in front of it.
Line-interactive inverters are the most advanced class of devices. In them, the input voltage is immediately converted into direct current supplied to the output inverter, and the battery is connected between the blocks. In a similar way (if you do not take into account the battery), a conventional welding inverter is arranged.Thus, the supply voltage is always stabilized, and when it is turned off, there are no delays in switching the UPS output from the external network to the inverter.
how to connect the boiler to the generator
This article deals only with the problem of connecting gas boilers to a generator.
And you are reading this article for two reasons:
- you already have a boiler and a generator, and the boiler does not want to work with the generator, while the gas burner tries to light up, but goes out after 3-5 seconds.
You only plan to buy a generator to power the boiler in the event of a power failure.
There is only one reason - the absence of a solid zero on the generator. Each modern boiler has a device that controls the presence of a flame in the combustion chamber. This is called "gas control". The principle of operation is to continuously measure the ionization current flowing between a metal pin isolated from the burner body and the combustion chamber body itself. A “phase” is applied to the pin, and the phase is 220 volts in relation to the “ground”, and the case is the “ground” - 0 volts. The boiler control board measures the ionization current, and if it is within acceptable limits, then everything is fine, gas is supplied, there is a flame, the gas burns out, there is no danger. In the event that there is no ionization current, or it is small (less than 20mA), the control board regards it as the absence of a flame in the combustion chamber and gives a signal to re-ignite the burner, and so on several times. If the ionization current does not appear, the gas supply is blocked for safety reasons.
In Generators that do not have zero, there is a sinusoidal voltage with an amplitude of 220 volts at the output, but this voltage, or, more correctly, the potential difference, is present between two "holes" in the output socket. And if you measure the potential difference between the “body” of the generator and each of the “holes” of the outlet with a voltmeter, then 220 volts will not work - and the tester will show 110 and 110 volts at idle, and for example 50 and 170 volts under load. If the power plug from the gas boiler is plugged into such a generator, then not 220 volts, but 110 will be supplied to the pin. This voltage will not be enough for the normal value of the ionization current and the gas control system will work.
What to do? The conclusion suggests itself as follows - you just need to connect one of the holes in the output socket of the generator to zero (zero bus at home). But this cannot be done for inverter generators - the zero bus is connected at the input to the house with an earth bus. Therefore, it turns out that you are shorting one of the outlets in the outlet to the same generator housing, because. the generator housing must be grounded according to the operating rules. In this case, the probability of failure of the generator coil is high.
There is only one way out - the installation of an isolation transformer. The connection diagram is shown in fig. Physically, we separate the output circuit of the generator from the input circuit of the boiler and have every right to connect one of the transformer outputs to the neutral bus of the house. Such a connection will not negatively affect the generator coils. Another plus when installing an isolation transformer is its ability to smooth out sudden voltage surges. A transformer is a coil, and a coil is an inductance, and an inductor always resists a sharp rise (front) of the signal.
BAXi specialists, link to the forum site of the BAXI boiler manufacturer, advise solving this problem using a specially designed Teplocom GF device.
How to insure the operation of the boiler
In such conditions, many boiler owners prefer to back up their heating power supply. There are opportunities for this, it is not forbidden, and the market offers a choice. You can use batteries in conjunction with inverters. This device is similar to a computer UPS, only slightly more powerful.As a rule, boiler automation consumes quite a bit of electrical power, but this already depends on the overall configuration of the heating system. If it has pumps, then often their work is necessary, that is, they not only increase the efficiency of the circulation of the coolant, but are included in the heating project as a necessary element.
Then the total energy consumption increases.
Also, in some cases, autonomous generators based on internal combustion engines may be suitable: gasoline or diesel generators. Gasoline generators can be powered by a gas line, if a particular model allows the replacement of the carburetor with a special device. There are models that already provide for switching from petrol to gas. There are generators with gas equipment that can be connected to natural or liquefied gas.
Of course, to power an autonomous power plant designed to generate electricity for the needs of a gas boiler and other heating equipment, the gas version of the engine would be best suited. With sufficient power - from 10 kW - such a power plant could back up the entire electrical network of the cottage during a power outage. The market offers a lot, but this solution is not cheap.
The boiler automation system consumes power on the order of one to two hundred watts - what is needed to power the gas solenoid valve and draft, flame and line pressure sensors. If there are pumps in the system, then the power consumption increases significantly: a household single-phase heating pump has a power consumption of 300 watts and more. Under such conditions, the load on the inverter increases and requires very expensive equipment.
Many boiler owners are forced to look for cheap solutions - this is due to the level of average income in Russia. Is it possible to use a gas generator for a boiler? This solution seems to be very effective: the cost of gasoline generators is low, and in many cases the power is sufficient.
Unfortunately, the stability, frequency and shape of the output voltage provided by a gasoline generator for a gas boiler may not be sufficient in the case of a cheap model.
If an inexpensive generator feeds boiler automation in a system without pumps, then its power is quite sufficient, but non-sinusoidal and “jumping” voltage can lead to unstable operation of the gas valve or electronics power supply. Modern power supplies are all pulsed, they are quite tolerant of power supply errors from the mains, but when powered by an autonomous generator with low quality voltage, they can work unstably and even fail. Control units and controllers consume power on the order of several tens of watts.
Conclusion
When choosing a gasoline, gas or diesel generator for a boiler, you should understand in detail, using the documentation for the gas boiler and, especially, its electrical part, what voltage is required to power the boiler control circuit.
Please note that this also includes pumps and other equipment, if they are in the system and their work is necessary!
Specify the power consumption of the entire heating system and add a 20-30% margin. Do not forget about the number of consumer phases and their rated voltage. It is better to take even 50% power reserve from a gas generator, as this will unload the engine and generator, reduce engine noise, increase fuel economy and significantly extend the overhaul life of both the engine and the generator.
The AC voltage generated by the inverter may not be sufficiently close to a sinusoidal waveform. In the simplest models, the voltage shape is rectangular; in other cases, another step is added.Supplying pumps with this voltage will cause increased vibration of their mechanical parts (due to uneven torque) and accelerated wear of parts. There may also be interference in the boiler electronics.
If the boiler room requires good quality alternating voltage (“pure sine”), then it is better to purchase a synchronous type gas generator with voltage and frequency stabilization. Video on this topic
Electronic inverters of sufficient power, which bring the output voltage shape closer to a sinusoidal one, are still very expensive.
If you are unable to resolve all technical issues yourself, please contact the experts and follow their advice when consulting with sellers. Only in this way you can make the best choice and get a solution to all your problems.
