11.5.1. Heating and ventilation of a motor van of GAZ-2705

The system of heating is calculated on continuous work for a long time and provides repeated exchange of air in a cabin, the necessary speed and air temperature, temperature of surfaces of a cabin.

Fig. 10.22. Main heater: 1 — a bracket; 2, 4 — levers of an axis of gates; 3 — an arm of fastening of covers of drafts of the drive; 5 — a clamp; 6, 7, 17 — covers of hummock drafts; 8, 9 — laths of the drive of gates; 10 — the protection cover; 11 — the OVU case; 12 — a fan cover; 13 — consolidation; 14 — the electric drive socket; 15 — the screw; 16 — the electric fan; 17 — two brackets of fastening of a flange of the electric fan; 18 — draft; 19 — a heating radiator; 20 — laying; 21 — a cover; 22 — the crane; 23 — a hose




Fig. 10.23. Installation of a heater: 1 — the handle of switching off of the crane and ventilation (heat — cold); 2 — the OVU control panel; 3 — a cap for GAZ-2705 or the handle of inclusion of additional heating; 4 — the handle of turning on of the fan of the main heater; 5 — the handle of distribution of a stream of air; 6, 7 — air ducts; 8 — the resistor; 9 — a bolt of fastening of OVU; 10 — an air inlet box; 11 — the plug; 12 — a tee; 13 — a casing; 14 — a holder; 15, 17 — hoses; 16 — nuts




Fig. 10.24. Distribution of air streams in a car cabin: 1 — OVU casing cover; 2 — the plug; 3 — a bolt of fastening of OVU; 4 — OVU casing; 5 — the distributor left; 6 — laying of a casing of OVU; 7 — a bracket; 8 — the screw; 9 — the distributor right




Heating of a cabin is provided with the air which is warmed up in a radiator of a heater 19 (fig. 10.22). External air passes through a lattice between a windshield and a cowl, changes the direction and separates from rain water. Then air from a box 10 (see fig. 10.23) an air inlet gets to a casing of a heater and depending on an arrangement of gates of admixture comes or through a radiator of a heater or directly to distributors of streams of air left 5 and right 9 (see fig. 10.24).
The Heating and Ventilating Installation (HVI) consists of the case of a heater 11 (rice. 10:22), including a casing 4 (see fig. 10.24) and a cover of 1 casing connected through laying by 6 brackets 7, distributors of a stream of air left 5 and right 9, fastening to a casing and a cover of a casing of a heater screws 8, a radiator 19 (see fig. 10.22), covers of a radiator 21, the electric fan 16, the covers of the fan 12, the gates of admixture of external air, gates of distribution of streams of air and gates of ventilation located in the OVU case and operated by laths of 8 and 9 protection covers 10 excluding damage of laths at installation.
On a cover of a casing of OVU the additional resistor 8 (see fig. 10.23) providing three speeds of rotation of the electric fan is installed.
Fastening of a heater is made on an arm via rubber plugs by 11 two bolts 9 to a wall of a motor compartment and a bolt 3 (see fig. 10.24) via the rubber plug to a cross-piece 19 (see fig. 10.23) an arm of fastening of OVU.
The crane of a heater is put in action by the microelectric motor through a mechanical reducer; the crane has two provisions — is completely open or completely closed.
The radiator of OVU is connected by a hose 23 (see fig. 10.22) to the crane of management of a heater and to the engine cooling system hoses 15 and 17 (see fig. 10.23). Hoses are connected to hoses of a motor compartment through the holder 14 attached to a compartment wall by two nuts 16. In system of hoses of a heater the tee 12 for elimination of air traffic jams in system of the OVU pipelines is established when filling (replacement) with cooling liquid of the cooling system of the engine.
OVU is connected to the air distribution channels executed in the dashboard through air ducts 6 and 7 (see fig. 10.23).

Fig. 3.1. Governing bodies





Fig. 10.25. Control panel of heating and ventilation




Control of OVU is exercised of the regulators 1, 2, 3 and 4 (fig. 10.25) located on the control panel of heating and ventilation (see fig. 3.1, poses. 14).
1 — the handle of the regulator of distribution of streams of air on a cabin:
— air arrives to wind and to side glasses;
— air comes to the area of a breast of the driver and passenger;
— air comes on wind and side glasses, to a breast and to legs of the driver and passenger;
— air comes only to legs of the driver and passenger;
2 — the handle of the regulator of amount of the air coming to a cabin. Has four provisions:
— it is switched off;
— minimum productivity of the fan;
— average productivity of the fan;
— maximum productivity of the fan;
3 — a cap (for GAZ-2705) or the handle of the regulator of intensity of warming up of air in a cabin of GAZ-2705 of "Kombi" or in inside of buses
4 — the air temperature regulator handle in a cabin (the handle at the same time operates the crane of a heater and gates of admixture). Extreme left position of the handle (a wide part of a blue symbol) corresponds to the ventilation mode. In this position of the handle the crane of a heater is closed, and the admixture gates operated by draft 18 (see fig. 10.22), the channel of intake of external air to a radiator of a heater is completely blocked and the channel of ventilation is completely open. Intermediate and extreme right provisions of the handle 4 (see fig. 10.25) (a wide part of a red symbol) corresponds to the heating mode. In this mode at turn of the handle on 9 ° clockwise the crane is open, gates of admixture partially opened the channel of intake of external air to a radiator of a heater and the channel of ventilation (intermediate inclusion of system of heating) is partially blocked. At extreme position of the handle right (clockwise) the channel of ventilation and all stream of external air is completely blocked goes through a heater radiator.
For heating of a cabin it is necessary to open the heater crane, to turn the handle 4 (see fig. 10.22) clockwise on a corner not less than 9 ° and further turn of the handle 4 to pick up comfortable air temperature.
Elimination of hoarfrost and condensate.
From wind and side glasses it is necessary for bystry removal of hoarfrost and condensate:
- to install the air 1 distribution regulator (fig. 10.22) in situation;
- 4 to install the regulator of air temperature in extreme right situation (a wide part of a red symbol);
- to install the regulator of amount of air 2 on the maximum productivity of the fan.
- it is necessary for obtaining comfortable climate:
- to install the regulator of distribution of streams of air 1 in the situation chosen by you;
- 4 to establish by the regulator of temperature desirable air temperature (temperature of external air or thermal air from a heater);
- to turn the regulator of amount of air 2 of situation O in one of three provisions to receive the desirable speed of intake of air in salon.
The central and side ventilating grates on the dashboard have handles (levers) of control of gates which movement it is possible to change the direction of streams of air, to increase or reduce amount of the arriving air before full closing of the channel of intake of air.
For bystry removal of fogging and frosting of glasses install the handle 1 in the provision of the direction of a stream of air on wind and side glasses, the handle 4 — in extreme right situation (a wide part of a red symbol), and the handle 2 in the extreme provision of the maximum speed of rotation of the OVU electric fan right (clockwise).

Fig. 10.26. Distribution of air streams in a car cabin: 1, 6 — branch pipes of an obduv of side glasses; 2, 3, 4, 5 — branch pipes of an obduv of the driver and passenger; 7, 8 — air ducts of an obduv of legs of the driver and passenger


Distribution of air streams in a cabin is carried out through air ducts and branch pipes 1, 2, 3, 4, 5 and 6 (see fig. 10.26).
Side 2 and 5 (see fig. 10.26) and the central branch pipes 3 and 4 obduv of the driver and the passenger have control levers gates. Their movement it is possible to change the direction of streams of air, to increase or reduce amount of the arriving air, up to full closing of the channel of its receipt.
Overall performance of system of heating depends on temperature of cooling liquid in the engine which in cold season needs to be supported within 85 — 100 °C.
The system of ventilation is intended for creation of a normal microclimate in a cabin at operation of the car in summertime of year.
Systems of the forced and exhaust ventilation are provided in a cabin. Compulsory forced ventilation is carried out through OVU at the closed windows, the roof hatch (at its existence) and the closed heater crane. For inclusion of ventilation it is necessary to transfer the handle 4 (see fig. 10.25) to extreme left situation (a wide part of a blue symbol) and to establish by turn of the handle 2 the necessary speed of air supply in a cabin. Extreme right position of the handle 2 corresponds to the maximum speed of rotation of the electric fan. Choose, turn of the handle 1, distribution of streams of air in a cabin. By means of control levers to establish by gates of branch pipes the most comfortable direction of air. Compulsory forced ventilation should use in hot weather at small speeds of the movement of the car and on parking. At speeds of the movement of the car higher than 50 km/h nritochny ventilation can be carried out at the switched-off electric fan at the expense of high-speed an air subtime. Forced ventilation is carried out also through lowering glasses of doors.
The exhaust ventilation is carried out through the cracks connected with the atmosphere and located in the lower part of doors of a cabin.
Check of technical condition and maintenance of the heating and ventilating installation (HVI)
Maintenance of OVU comes down to periodic check of technical condition of a radiator of a heater, the crane and hoses of system, operation of the electric fan, OVU gates and branch pipes on the dashboard distributing and directing streams of the air given to a cabin.
At dribble of cooling liquid of the engine in a cabin it is necessary to check first of all reliability of fastening of hoses of system of heating by collars, tightness of a radiator and the crane of a heater. At detection of a leak it is necessary to improve coupling collars in places of connections 13 (see fig. 10.23). If the dribble reason — the heater radiator (liquid leaks from the OVU case), a radiator need to be removed (see. "Dismantling and repair of system of heating") to establish the place of dribble of liquid and to eliminate a leak.
Radiator of a heater 19 (see fig. 10.22) a combined design, tubular and lamellar with plastic tanks. The core of a radiator is made of aluminum tubes and the aluminum cooling plates. On both sides of a core the metal bottom with rubber laying is established. Laying condenses the ends of tubes, and the tank installed on this laying is drawn in to laying by otgibny short moustaches. In tubes screw plastic turbulizers for bigger renting of heat from a heater radiator are established.
If the leak is found in the place of consolidation of tubes by rubber laying, to eliminate with preload of otgibny short moustaches of a bottom of a tank. For this purpose it is necessary to establish reliably a radiator on a rubber rug and to slightly draw in a mustache of a metal bottom in the place of dribble. If liquid leaks through the damaged tubes, the radiator should be changed for new. In case of repair it is necessary to remove tanks, having unbent tank bottom short moustaches and to put repair tubes of smaller diameter with the subsequent their dornovaniye (i.e. with increase in internal diameter of tubes).
At violation of tightness of the crane 22 (see fig. 10.22) it needs to be removed and examined. If the leak on connection of a cover with the case is found, to tighten screws of fastening of a cover or to unscrew screws and to replace laying. For check of operability of the crane it is necessary to put a finger to the case of the crane and to turn the handle 4 (see fig. 10.25) on 9 — 10 ° from extreme left situation clockwise.
At the same time food on the electric drive of the crane moves and the click of operation of the locking gate has to be listened. If there is no click, the electric drive is faulty. The crane needs to be replaced.
The OVU electric fan does not work - or works with the increased noise.
Violation of power supply of the fan, jamming of a rotor of the fan in the heater case, jamming of a shaft of the electric motor in bearings or unreliable contact in the socket of electrical wire 14 can be the cause of a stop of the electric fan 16 (see fig. 10.22).
To eliminate jamming of a rotor of the fan, it is necessary to remove the electric fan, to be convinced that two brackets of fastening of a flange of the electric fan 17 on the place and do not get jammed an electric fan rotor. It is necessary to turn a rotor and to be convinced that the shaft of the electric motor rotates freely. If rotation is complicated or the rotor does not rotate at all, replace the electric fan.
If at turn of the handle 2 (see fig. 10.25) turning on of the fan the speed of a stream of air does not change, it is necessary to check reliability of connection of resistance 8 (plugs) to a plait of wires or to replace resistance.
Dismantling and repair of system of heating and ventilation
For removal of a radiator of a heater:
- to merge cooling liquid from the engine cooling system (3 — 4 l);
- to weaken collars of fastening of hoses 15 and 17 (see 10:23) to unions of a radiator 19 (see fig. 10.22);
- to disconnect hoses:
- to unscrew three screws 24 (see fig. 10.22) fastenings of a cover of a radiator and to uncover 21 with laying 20;
- to take out a radiator of a heater 19 of the case 11.
Installation of a radiator of a heater is made upside-down.
For removal of the crane 22 (fig. 10.22) a heater with the electric drive needs to weaken homuga of fastening of hoses to the heater crane, to disconnect hoses and to remove the crane, previously having disconnected a food plait.
Installation of the crane is made upside-down.
For removal of the electric fan - it is necessary to open a cover of a ware box on the dashboard. To unscrew four screws of fastening of a ware box and to take out it together with a cover from a dashboard nest.
Then to unscrew two screws 15 (see fig. 10.22) fastenings of a cover of the electric fan and to remove ee from the heater case. To disconnect a wire of connection of the electric motor 14 (to disconnect a block of wires), to remove a sealant of electrical wires 13 and to take out the electric fan from the heater case.
Installation of the electric fan is made upside-down.
Removal of the control panel requires removal of the dashboard (work is carried out at service station).
Violation of distribution of streams of air from OVU

Fig. 9.25. Measurement of a gap from a gear wheel end face to a cup of a persistent ring at completely involved anchor of the traction relay




One of causes of infringement of distribution of streams of air is weakening of brackets 1 (see fig. 10.22) fastenings of covers of 6 and 7 hummock thirsts of the drive for an arm 3. As a result at turn of the handle 1 (see fig. 9.25) draft is bent, and the gate does not work. The bracket (brackets) needs to be recorded reliably in arm openings, and in case of their breakage to replace.
The wrong position of gates in distributors of air 5 and 9 is other cause of infringement of distribution of air (see fig. 10.24). It is necessary for elimination of this shortcoming: the handle 1 (see fig. 10.25) to put in position an obduv wind and side glasses, at the same time the lever 2 (see fig. 10.22) axes of the gate has to be in extreme right situation, and the lever 4 — in extreme left situation (clockwise). If it does not occur, then it is necessary to release a lath (laths) 8 and 9 of a clamp 5, to put the lever (levers) in the positions stated above and again to record laths in clamps.