How to choose a gas boiler to work on liquefied gas

Choosing the correct gas boiler for your home’s heating needs is essential to guaranteeing both efficiency and comfort, particularly if you’re using liquefied gas. A well-selected boiler lowers your energy costs in addition to ensuring that your home is consistently warm. This article will walk you through the most important things to think about when selecting a liquefied gas boiler to meet the heating needs of your house.

The first step is to comprehend the fundamentals of how gas boilers using liquefied petroleum gas (LPG) work. LPG is stored in tanks and needs particular handling and equipment, unlike natural gas. When selecting an LPG boiler, you should take into account the space required for the installation of the tank as well as the fuel availability in your area. Before choosing, it’s critical to consider these logistical considerations.

Efficiency is yet another important consideration. Energy efficiency ratings are attached to modern gas boilers. Lower fuel consumption is typically associated with higher efficiency ratings, which is better for the environment and your wallet. We’ll look at how to understand these ratings and select a unit that produces the most with the least amount of waste.

Finally, the boiler’s size and output need to match the size of your house and the amount of heat your family needs. In the long run, an oversized or undersized boiler can result in inefficiencies and higher expenses. We’ll go over how to determine the ideal boiler size for your area in order to get the best possible performance.

By the time you finish reading this article, you ought to know exactly what to look for in a liquefied gas boiler and how to make a decision that will keep your house warm without going over budget.

Criteria	Details
Boiler Type	Choose between a combi, system, or conventional boiler based on your home"s heating needs.
Capacity	Consider the size of your home and the number of bathrooms to determine the kW capacity required.
Efficiency	Look for high-efficiency models to save on gas bills and reduce environmental impact.
Brand and Warranty	Opt for reputable brands with good warranty conditions to ensure reliability and service support.
Installation Requirements	Ensure your home meets the installation requirements for a gas boiler, including venting and gas line specifications.
Cost	Factor in both the upfront cost and the ongoing operating costs.

What are gas boilers on liquefied gas?

It is important to note right away that there are standard gas units that can be used for this purpose, as their factory design allows for the possibility of readjustment from natural gas to LPG and vice versa. Special boilers made to operate exclusively on liquefied fuel are not available.

To guarantee more thorough fuel production, a boiler that is suitable for LPG should also have a low operating pressure (3-5 mBar).

What they are for and how they are used?

Actually, there are a number of factors that contribute to homeowners’ preference for liquefied fuel heating, but these can be categorized into several main categories:

• temporary lack of supply or connection of a direct gas pipeline;
• Other resources are difficult or expensive to obtain locally;
• the need to heat small-sized houses (40-100 m 2 ).

The process of gasifying the site is frequently postponed (it takes time to gather funds, obtain a permit, approve the project, etc.), so during this time LPG is helpful.

Cylinders are less expensive than other fuels, particularly electricity, if we do not take into account the possibility that someone lives in a coal-mining region.

The best part is that a gas boiler using liquefied gas is appropriate for small homes because installing one to three cylinders doesn’t require any space or permission.

Device and principle of operation

An LPG boiler uses fuel to burn and then directs that energy to heat the coolant (water) that is circulating. This is how any similar device works.

But direct supplies of liquefied gas are not possible. Because of its excessively large nozzles (holes), the standard injection burner is simply not made for this type of fuel. The excessive gas can cause the equipment to overheat, deform, or even explode.

Because of this, it is first required to connect a reducer (pressure equalizer) and install smaller-diameter atomizers. This is because the pressure drop at the cylinder outlet will guarantee that the fuel transforms from liquid to gaseous state. And it goes into the combustion chamber already in this state.

Other than that, the liquefied gas-operating heating boiler is exactly like the conventional unit in terms of design.

Operation specifics

To guarantee the continuous heating of the residence, it is imperative to set up a storage facility whose capacity aligns with the quantity of gas reserves:

• a group of cylinders on a ramp – a group of 4-15 cylinders with a capacity of 0.2-0.7 m 3 ;
• mobile gas holder – movable tank with capacity of 0.4-1.4 m 3 ;
• stationary gasholder – a built-in tank with a capacity of 3-50 m 3 .

A sturdy steel box containing a number of cylinders on a ramp and collectors is moved 1-2 meters away from the house or fixed to the building’s wall (if the fire resistance is greater than III degree). Short-term supplies (one to three cylinders) should not be kept underground; instead, they should be kept inside the house.

LPG storage is not allowed in basements! If there is a leak, heavy gas collects on the ground floor of the building, posing a risk of explosion and fire.

A mobile or mini gas holder is mounted on a trailer, similar to a car trailer, and it is positioned no closer than 10 or 12 meters from the residential structure. An electric heater that is a part of the general heating network is installed in the sealed container to prevent condensate from freezing during cold weather.

A stationary gas holder is always installed underground. Gas pipes are run to the home or boiler room, and the tank is entirely submerged (with the exception of the lid and control elements). The soil around the walls means it doesn’t require extra heating.

Depending on the tank volume, the technical supervision authorities establish the minimum distance between a stationary gas holder and a residential building:

• distance ≥ 10 m – volume from 3 to 10 m 3 ;
• distance ≥ 15 m – volume from 10 to 20 m 3 ;
• distance ≥ 20 m – volume from 20 to 50 m 3 .

The best option for ensuring that the heating system runs continuously is unquestionably a stationary gas storage unit; one or two refills will last the entire season.

Generally speaking, any of the following arrangements for the location of liquefied fuel storage are deemed appropriate, provided that safety regulations are followed:

• the gas container must not be exposed to direct sunlight;
• its constant external temperature should not exceed + 43…+ 45 °C;
• gas pipes should be laid below the soil freezing level.

Additionally, the gas boiler itself needs to be in a good location. Residential areas with gas stoves and radiators are acceptable locations for 10–60 kW units, such as a typical kitchen (10–15 m³).Rooms with street access that are suitable for 70–350 kW appliances should have a separate boiler room (15–25 m³).

LPG consumption

The device’s operating conditions and technical attributes, namely capacity and efficiency, determine the quantity of fuel used for heating. For instance, the passport data indicates that the Zhukovsky AOGV-17,4-3 boiler, which has a 17 kW capacity and an efficiency of 90%, uses 0.7 kg or 1.3 l of liquefied gas per hour.

By taking the average value and the fact that the cost of refueling in 2020 is 12–23 rubles/l, you can roughly calculate the cost of heating the house for a specific amount of time:

• per day (24 hours) – 1.3 × 24 = 31 liters × 17 ≈ 527-558 rubles;
• per month (30 days) – 31 × 30 = 930 l × 17 ≈ 15810-16740 rubles;
• per season (half a year) – 930 × 6 = 5580 liters × 17 ≈ 94860-100440 rubles.

Remember that a 50-liter cylinder actually contains 40–42 liters of propane–butane mixture; 15-20% of the free volume is utilized to expand the gas vaporization area, and filling the cylinder too full reduces the amount of gas produced. implies that one cylinder will last for 1.5 days at a flow rate of 1.3 l/h.

Not all is lost though; the figures in the passport are based on the assumption that the unit will always operate in the 24/7 mode at maximum capacity, which in practice only occurs during very severe frosts. The boiler only runs for 10–14 hours a day in warm weather, so the final result can be safely lowered by 30–50%.

How to pick a room thermostat to reduce your monthly heating expenses by up to 30%

Reviews of household boiler units: advantages and disadvantages

It is clear from reading the evaluations of LPG boiler owners that these appliances are fairly dubious; they have both clear advantages and disadvantages.

Benefits and drawbacks of the device when running on less gas:

Pros	Minuses
autonomy – such devices do not depend on the growth of utility tariffs, nor on the stability of the gas mains	refueling price – if you do not bring the gas yourself, the price includes the amount spent on its transportation
Versatility – back-setting (to natural gas combustion) is possible at any time with minimal effort	regular maintenance – the small nozzles are clogged with sulphurous substances, so they need to be cleaned frequently
cleanliness – cylinder fuel, unlike solid fuel, when burning does not form ash, dust, cinders, smoke, etc. д.	high fire hazard – storing fuel reserves on the site requires strict observance of safety measures
environmental friendliness – most (91-95%) of the LPG waste is carbon dioxide, which is then absorbed by plants	weather dependence – in winter there is a problem of snowdrifts preventing refueling and icing of the reducer
simplicity of the system – the lack of complex parts provides protection against accidents and breakdowns, as well as ease of maintenance	Additional costs – the final price depends on the estimate of excavation works, the length of the gas pipeline, the volume of the vessel, etc.

It is required of users of LPG heating systems to periodically check the amount of fuel left in the connected tank. This is a little inconvenient because it requires regular refilling of the gas cylinders or pumping a large enough volume of gas into storage all at once.

Even though it’s so easy, refueling involves caution because even the smallest mistake when attaching the gas line can result in a leak.

When choosing a gas boiler for use with liquefied gas, it’s essential to consider several key factors to ensure efficiency and safety. First, determine the appropriate size of the boiler based on the size of your home and your heating needs, as an improperly sized boiler can lead to inefficiency and increased costs. Look for models designed specifically for liquefied gas, as they differ from those meant for natural gas. Additionally, pay attention to the energy efficiency rating of the boiler—higher ratings indicate more cost-effective operation over time. Finally, ensure that installation and maintenance are performed by qualified professionals, as correct installation and upkeep are crucial for the safe and efficient operation of the gas boiler.

How to choose an LPG gas boiler?

It is impossible to determine which liquefied gas boiler is better to select in the absence of data because the boiler’s features must precisely match the room’s specifications. Consequently, it is advised that you speak with experts or gain your own understanding of the technical specifications before making a purchase.

Convection or condensing

The method used to use the heat energy produced during fuel combustion determines how efficiently the LPG-consuming unit operates:

• convectional – heats the heat carrier at the expense of the energy obtained from direct gas combustion, at the same time a part of heat is lost, leaving together with waste gases;
• condensing – "extracts" additional heat by cooling the smoke and condensing the steam in a low-temperature heat exchanger (economizer).

It goes without saying that the condensing boiler is more profitable because it saves 15-20% on fuel, but the cost of the unit is 1.5–2 times higher than that of a conventional boiler.

Distinctions and standards for selecting condensing gas boilers with competence

Wall-mounted or floor-mounted

The primary distinction between equipment mounted on walls and floors lies not only in their positioning, but also in the structural component:

• wall-mounted models – must "fit" in a compact lightweight housing, they are characterized by a steel/copper heat exchanger, usually more functional automation;
• Floor standing models – are not restricted in weight and size, so they can be used in the t. ч. and cast iron heat exchanger, as well as a wider range of power (10-60 kW).

Wall-mounted units come with automation, a circulation pump, and other energy-dependent components; in essence, the customer receives a thermal mini-station that is ready to operate. While floor standing boilers are not as independent of electricity, many of them are.

Single-circuit or dual-circuit

The functions that the gas equipment is intended to carry out and the precise distribution of the heat generated are determined by the number of circuits:

• single-circuit – designed directly for space heating;
• two-circuit – responsible for both heating and hot water supply (DHW).

Given the high consumption of LPG, it makes sense for DHW to connect an indirect heating boiler to a single-circuit boiler in order to save money on needless expenses. However, two-circuit models are still in demand as well.

EFFICIENCY

The appliance’s efficiency and the cost-effective use of energy resources are measured by the coefficient of performance, or COP.

The efficiency value is crucial for boilers that primarily use reduced fuel. While models ranging from 85% to 97% are available, it makes no sense to buy units with an efficiency below 88% because, because of the relatively high fuel consumption, the cost of gas heating the house will "catch up" with electricity.

Minimum required power

A simplified formula can be used to approximate the boiler capacity: 1 * kW of energy for every 10 m^2 of area.

* approximation, accounting for a moderate climate and 2.5–3 m ceilings.

For instance, the minimum power needed by the unit to heat a 120 m³ average house in Moscow or the Moscow region would be 120÷10×1=12 kW.

Additionally, we advise planning for potential severe frosts and purchasing a boiler with a reserve of 15-20%, or roughly 14 kW for a 120 m 2 home. If not, it will be difficult to maintain a comfortable temperature during the chilly winter months, and operating at maximum capacity will cause the parts to wear out sooner.

How to compute the necessary boiler output precisely Formula, correction factors, and individual calculations

Additional criteria

It’s also important to take note of the following additional features, which taken together will increase the gas boiler’s productivity and safety:

• safety kit – consists of a safety valve, draught controller, active flame sensor, air vent and backup power supply unit;
• functional automation – includes modules for auto ignition, flame regulation, self-diagnostics, mode programming and external control;
• heat and sound insulation – specially selected cladding prevents heat losses (increasing the efficiency of the appliance) and reduces the noise from the burner operation.

When the boiler is indoors, high-quality insulation can help eliminate the pops, crackling, and vibrations that come with autoignition.

The best manufacturers and models: characteristics and prices

The functionality and quality of the unit are determined by the country of manufacture; since it is bought years in advance, it is not worthwhile to haggle for questionable equipment that is sold in China. Choosing well-researched products from Russian or European producers is preferable.

Protherm Gepard 23 MOV

An established 23 kW two-circuit mounted model. features a copper plate heat exchanger, which is more corrosion resistant and heat conductive, and an open combustion chamber for natural draft. Excellent for the price range; automation enables you to optimize fuel consumption (maximum 1.9 l/h) and boiler operation.

Protherm (Protherm), Slovakia is the manufacturer.

Bosch Gaz WBN6000-24C RN S5700

The German BOSCH 24 kW is constructed from better materials and does not have strict requirements for coolant and fuel quality. It is completely suited to Russian conditions, withstanding pressure changes, abrupt drops in temperature (down to -35 °C), and variations in voltage. Three-speed pump, thermal insulation in the casing, and a modulating fan ensure economical gas consumption (max 1.5 l/h).

Russian-German manufacturer Bosch Thermotechnik (Bosch Thermotechnik).

Buderus Logamax U072-18K

With its 18 kW capacity and maximum fuel consumption of 1.5 l/h, we can declare that this low-cost single-circuit boiler unit is among the best gas boilers on liquefied petroleum gas for heating a private residence. It can be easily converted to DHW thanks to a three-way valve and an integrated diaphragm expansion tank. The following characteristics, which define the model’s high reliability,

Manufacturer: Russia-Germany Buderus.

BAXI SLIM 1.150 I

The well-known 15 kW floor standing Italian boiler is well-known for using the least amount of gas possible (maximum 1.1 l/h). It comes pre-configured with a cast iron heat exchanger, control module, and weather-dependent automation. An integrated self-diagnostic option is also included. Another significant benefit is its modest size; its width, for instance, is just 35 cm.

Italian manufacturer Baxi.

Wester Lemax Clever-30

Wall-mounted, 30-kW single-circuit domestic appliance that is independent of electricity availability. It can be used in a system where the heat carrier is forced or circulated naturally. Its continuous smooth flame modulation, which ranges from 30% to 100%, allows for a significant fuel consumption reduction (maximum of 1.7 l/h). A high level of economic efficiency is accompanied by a level of reliability comparable to that of European manufacturers.

The steel heat exchanger is the sole major drawback; it has a finite resource life of 10–14 years.

Russian manufacturer Lemax (Lemax).

Prices: summary table

Comparison rating of boilers using fuel that has been liquefied:

Boiler model name	EFFICIENCY, %	Power, kW	LPG consumption, l/h	Price, rub.
Protherm Gepard 23 MOV	90	23	≤ 1,9	51 000
Bosch Gaz WBN6000-24C RN	92	24	≤ 1,5	38 500
Buderus Logamax U072-18K	92	18	≤ 1,5	39 500
BAXI SLIM 1.150 I	90	15	≤ 1,1	78 000
Wester Lemax Clever-30	90	30	≤ 1,7	51 000

Boiler unit conversion to bottled gas

The conversion of the boiler to liquefied gas should be relatively simple in theory; the main task is to replace the burner or the nozzles that consume fuel. If the unit is automated, then the adjustment of the gas valve and the reconfiguration of the electronic board are as follows (per the enclosed instruction manual).

However, it is preferable to get in touch with a licensed gas company rather than trying to mess with the boiler’s internal components yourself. The task can be completed by specially trained personnel in no more than 30 minutes, and the total cost of the work, including the purchase of all necessary parts, is estimated to be between 2.5 and 3.5 thousand rubles.

Selecting the ideal gas boiler for your house is essential if you want to save energy and have effective heating. The size of your home and your heating needs should be taken into account when choosing a liquefied gas boiler. In addition to offering reliable comfort, a well-chosen boiler lowers the possibility of excessive utility costs. Make sure the boiler’s capacity fits your requirements; otherwise, it may result in inefficiency and higher expenses.

The boiler’s energy efficiency rating is another important consideration. In comparison to traditional fuels, liquefied gas is more economical and environmentally friendly. As such, modern boilers are built to optimize the energy output from this fuel. Seek out high-efficiency boilers; these are frequently certified Energy Star models. This guarantees that the boiler will use the fuel more efficiently, reducing your heating costs and carbon footprint.

Furthermore, one should not undervalue the boiler’s robustness and dependability. Select models and brands that are renowned for their durability and low maintenance requirements. A high-quality boiler may cost more up front, but because it will require less maintenance and replacement less frequently, it will end up saving you money over time. Take into account the accessibility of replacement parts and trained professionals in your region as well, as these factors will help to simplify upkeep and any required repairs.

Lastly, get advice from a certified installer or heating specialist before making a purchase. They can offer tailored guidance based on the features of your house and the local climate. Their knowledge can help you select the model that best suits your needs in terms of both price and space, as well as guaranteeing a flawless installation and top performance. Recall that installing the proper boiler not only improves your home’s warmth and comfort but also marks a step toward more intelligent and sustainable energy use.

Video on the topic

LPG heating – boiler conversion!!!