Operating principle and design of the VAZ-2115 heating system

If the heater in the car does not work, especially in the cold season, there is a possibility of being left without a means of transportation, since in the cold you can simply freeze inside the car. In severe frosts, it is very difficult to clear the windshield of ice to ensure visibility, and with a non-working stove this becomes doubly problematic. You may not even be able to get to a service station.

But most often, if you know the operating principle, circuit and design of the VAZ-2115 stove, you can solve the problem on the spot yourself.

The design and principle of operation of the VAZ 2114/15 stove

The heating system of the VAZ 2114/15 is designed to heat the air entering the passenger compartment. Its design is the same in cars with injection and carburetor engines. The coolant heated by the engine flows from the cooling system into the heater radiator, which is blown by a fan. The flow of warm air created in this way enters the cabin through the air duct system. The intensity and direction of air flow is regulated using deflectors and dampers. The interior heating system of the VAZ 2114/15 can operate in several modes.

The VAZ 2114/15 stove is designed quite simply: 1 - assembled heater; 2 — protective casing; 3 - seal; 4 — front air duct; 5 — rear air duct; 6 — rear air duct; 7 — right nozzle; 8 — right side air duct; 9 — right side nozzle; 10 — intermediate body; 11 — central nozzle; 12 — draft of the windshield heating flap; 13 — heater control levers; 14 — control handle for the heated windshield damper; 15 — heater control handle; 16 — symbol plate; 17 — control handle for the foot heating damper; 18 — right air duct; 19 — interior heating air duct; 20 — heater control damper rod; 21 — heater valve control rod; 22 — heater valve; 23 - leg heating damper rod

Refinement of the pipe

When the air flow from the left deflector is too small, you can force its intensity. To do this, you need to insert a small (about 50 mm) fan into the pipe. A cooler used in computers is suitable for tuning.

First remove the deflector. Make a hole for the cooler and install it. Seal. Put the branch pipe with the fan in place. Restore electrical. An alternative is to connect the cooler directly to the heater contacts. In this case, it will only work when the ignition is on.

Properly carried out modernization will add warmth to the interior and save the owner of the VAZ 2114 from many problems.

Stove design

The VAZ 2114/15 stove consists of the following elements:

• Fan.
• Windshield defroster.
• A distribution flap that directs air flow to the central and side deflectors, to the lower and upper parts of the cabin.
• Control valve.
• Stove radiator.
• Duct that directs air flow to the legs.
• Internal air duct.

The stove consists of a fan, dampers, radiator and air ducts. Blue and red colors indicate the flow of cold and hot air, respectively.

see also

Comments 213

I solved the problem by setting the thermostat to 87 degrees, the car became very warm, and I unfastened the faucet adjustment, leaving the faucet in the open position, I regulate the temperature only with the GH lever that you fixed.

Good evening. One of these days I will have to install a thermostat on Grants, and I will also have to turn off the tap. What is the situation with adjusting the air temperature? I bought a gearmotor from tens for the hot-cold damper. I want to plug the central air ducts

And after replacing the heater radiator, the airflow in my legs worsened, before it blew heat everywhere, now it blows heat everywhere but not in my legs, as you indicated, I did a cable and nothing

Yes, I'm sick of these 9-stove stoves, G completely warm, I always did everything, and the copper radiator and thermostat from 10 and closed the damper. In short, someone like me is full of crap until I installed the Opel stove with normal pipes and a torpedo And Schaaa I still I installed the heater from the 9 and their torpedoes are squeaky, but not to life

Unfortunately, this cannot always help; the heater radiator - copper or aluminum - plays a very important role. The aluminum is complete crap, (price is about 350-400 rubles) I installed a new one after completely cleaning and gluing the stove, the result was frozen sides and from the middle to the top of the windshield, I had to scratch it with my nails to get home. Afterwards I decided to splurge and bought a copper one (1400 rubles), although I didn’t immediately believe that it would be any good, but I was very mistaken! The difference is huge: 5-6 times the copper one justifies itself. And one more thing about the GC damper. If you turn the stove towards you and pay attention to the gaps of the GC damper at the ends (i.e. on the right and left sides, through the central air duct), then you will see just GAPs there! That's why some people have cold air coming into the side deflectors while the forehead of the leg and the center are warm. And even if you pull the damper with very great force, it will not help you much.

Heater fuse and reasons for its failure

Often the cause of malfunction of most components and systems of a car is a blown fuse. The stove is no exception. Failure of a 30A heating system fuse causes the fan motor to stop and air to stop flowing into the cabin. In this case, find an element marked F7 in the fuse block and replace it. The new fuse should also be rated 30A. If the fan does not work after this, the problem should be looked for elsewhere.

Heater fuse F7 is located in the mounting block under the hood on the driver's side

It is often difficult to determine that it is the fuse that has blown. It can fail due to a short circuit in the electrical wiring, a malfunction of the electric motor, severe clogging of the cabin filter and in a number of other situations. The difficulty lies in the fact that fuse F7 is simultaneously included in the rear window heating electrical circuit and is responsible for the cigarette lighter, glove compartment lighting and headlight washer motor. If it fails, all these components will not work.

Major electrical failures of the heating system of the VAZ-2115

If no changes occur in the heating system at any position of the switch knob, then most likely the system motor is faulty (the brushes are worn out) or there is no voltage at the terminals. But also in this case there may be problems with the ignition switch or mounting block (fuse F4 has blown).

It is important for the proper operation of the car's heating system that there is no more than 3 ohms at the engine ground (installed under the hood).

If the heater works normally at maximum engine speeds, and problems arise only at low speeds, then the cause of the malfunction most likely lies in the speed switch button or additional resistors.

If you turn on the interior heating system and hear a noise and the heater is not blowing properly, this also indicates an engine problem. Malfunctions may include jamming of the impeller or armature bearings. Malfunctions can be eliminated by replacing components or, if necessary, lubricating them. But, as a rule, these actions have a short-term effect and the problem returns.

Over time, any equipment breaks down and requires repair. Therefore, the heating system is no exception here, and the least that needs to be done for preventive purposes is to at least carry out periodic visual inspections and diagnostics. Don’t forget that over time the system ages and wears out, so the older the car, the more it needs to be prepared for the heating season.

Why the stove does not work or does not heat the air

If the stove fails, it either does not work at all, or it works but does not heat the air. In the first case, first check the fan wiring, starting with fuse F7. If the fuse is blown, replace it. Then they check the relay, which may not turn on the first time or only when the engine is warm. In this case, the relay is replaced with a new one.

Then the serviceability of the electric motor is assessed. To do this, power is directly supplied to its contacts from the battery. If the electric motor starts to operate at maximum speed, then it is in good condition. Otherwise, it will need to be repaired or replaced.

The intensity of the air flow is adjusted using a resistor having two spirals with resistances of 0.82 Ohm and 0.23 Ohm. In the first mode, the current flows through both spirals, in the second - only through a spiral with a resistance of 0.23 Ohms, in the third - bypassing the spirals, that is, without resistance at all. If the resistor is faulty, the fan will only operate in the third mode at maximum speed (handle in the extreme right position). The problem is solved by replacing the resistor, which is located on the driver's side above the accelerator pedal.

If the resistor is faulty, the heater fan will only be able to operate at maximum speed.

If cold air enters the cabin, this may be due to:

• Airlock. It could have formed when replacing the coolant, when the system was depressurized, or because there was insufficient amount of coolant in the system. To remove the plug, remove the heater radiator pipe, use a watering can to add antifreeze to the maximum and put the hose back in place. After starting the engine, coolant under pressure will displace the remaining air from the system.
• Stove tap jammed. This happens if the tap was not initially opened all the way, and during operation, oxide and scale formed on the inner surface, preventing the normal circulation of the liquid. You can try to open the tap using pliers or immediately replace it with a new one.
• The stove radiator is clogged. When using low-quality coolant, the radiator honeycombs may become clogged. The problem is solved by flushing or replacing the heat exchanger. The feasibility of washing is determined by the scale of contamination.
• Installation of a low-quality radiator. In a defective product, the honeycomb may be incorrectly soldered. The radiator should be replaced.
• Low pressure in the cooling system. If heat transfer increases at higher speeds, the pump needs to be replaced.
• Low coolant level. It is necessary to check the level and add antifreeze if necessary.
• Damage to the heater fan impeller. The impeller is carefully inspected and replaced if mechanical damage is detected.
• Cabin filter dirty. If it is heavily polluted, the power of the electric motor will not be enough to pump warm air into the cabin. The filter is replaced with a new one.
• Damage to the cylinder head gasket. If the cylinder head gasket is blown, white smoke will come out of the exhaust pipe. The problem is solved by replacing the gasket and dismantling the cylinder head.

If the stove is clogged, warm air will stop flowing into the cabin.

Design of heating radiators from LUZAR

LUZAR heating radiators are available in three types:

1. Tubular-plate, prefabricated, aluminum. It consists of aluminum plates through which aluminum tubes pass, inside which coolant runs. The tanks on such radiators are made of plastic. Heater radiators of this type are used for heating small-sized salons due to limited heat transfer; have the best rigidity and light weight, as well as the lowest price.
2. Tubular-tape, non-assembled (brazed), aluminum. The corrugated aluminum tape in such a radiator is located between aluminum flat-oval tubes. Radiator tanks of this type can be made of either plastic or metal. The design of non-assembled (brazed) aluminum devices is the most universal, allowing the creation of heat exchangers with any specified characteristics. Aluminum stove radiators are light in weight and relatively high rigidity, as well as at optimal prices.

3. Tubular-tape, non-assembled (soldered), copper-brass. The design is very close to type 2 - between the copper flat-oval tubes there are copper strips folded in the form of an “accordion”. At the same time, the tanks on such heating radiators are made of brass - in order to increase the overall rigidity of the structure. Copper heating radiators - due to the high specific heat capacity of copper - have excellent heat transfer rates. However, due to the high softness of copper, heating radiators made of this metal are forced to have a narrow tube and a large interval (step) between the tubes, which imposes serious limitations on maximum efficiency. Also, copper heater radiators have the highest cost and the lowest rigidity to torsion, fracture and internal pressure. In this regard, copper heater radiators are “outdated” and are gradually falling out of use.

LUZAR: time-tested and road-tested

LUZAR radiators have been awarded the “Radiator of the Year” award several times. For several reasons:

• Our products are not inferior to the original ones in quality and durability.
• Often it is our products that are “original”.
• We provide a warranty of 2 years or 125,000 kilometers.
• We check each model for leaks, and several models of each batch for corrosion and vibration resistance.
• You can buy stove radiators in all possible ways (more details in the “Where to buy?” section)
• We answer all customer questions openly and quickly

Make sure of this by calling 8-800-555-8965.

Heater dampers don't work

The distribution of air flows throughout the cabin is carried out by dampers, which, in turn, are controlled using cables. When these cables fail, problems arise with directing the air flow to the windshield or to the foot area. In addition, the damper that blocks the flow of air from the street begins to work incorrectly. In this case, adjustment of the damper drives is required.

Such situations can arise even on a new car. Slightly warm air begins to flow from the lower, upper and side deflectors, and hot air begins to flow from the center console. This is due to the poor build quality. There are gaps between the joints of the air ducts and the dampers, which leads to warm air entering only from the center console and heating the panel from the inside.

The drive cable is always taut. Therefore, over time it bends, breaks off or stretches. In this case, it is necessary to adjust the damper drive, which is performed in the following order:

• In the stove, we look for a bracket with which the cable sheath is held on the heater body.
• A galvanized metal lever located on the left side is pulled back. This position corresponds to the maximum opening of the damper.
• The length of the cable is tightened and adjusted. The long lever on the lever block in the extreme right position should open the damper completely.
• After adjustment, the cable is securely fixed.

Video: stove repair using the example of a VAZ 2114

Modernization of the heating system (stove)

In general, one point in the operation of the stove bothered me: even when the lever for adjusting the supply of hot-cold air (hereinafter simply the GC lever) is in the extreme right position, COLD air was always blowing on the windshield and especially on the side windows, despite the fact that the legs the blowing was already hot.

Let's figure out why this happens:

The design of the stove of the new model VAZ 2113-15

If there is at least a small gap in the place indicated by the arrow, then cold air will blow on the windshield anyway.

You can call this some kind of miscalculation of engineers.

Also, due to this design, the flow temperature is poorly regulated. As you already understood from the picture, if you move the GC lever a little, cold air will immediately blow into your face, and not diluted with hot air.

I think almost everyone has encountered this.

But the solution turns out to be as simple as 3 rubles.

I did it a little differently, but the meaning remained the same: press the GC damper as much as possible against the upper wall, thereby eliminating the gap there.

I simply removed the cable from the GC damper leash. Now the GC lever is only responsible for opening/closing the heater valve.

Then, using a piece of wire, I fixed the GC damper in the uppermost position.

I was amazed at the result: even at 40C of the engine, WARM air was already blowing on the windshield and, most importantly, on the side windows, even at the third fan speed.

Just like that, business for 10 minutes, and what is the result?