Volkswagen Polo Service & Repair Manual: Possible Concerns

Volkswagen Polo Service & Repair Manual / Refrrigerant R134a Servicing / Concerns / Possible Refrigerant Circuit Concerns / Possible Concerns

Note

The A/C system is functioning correctly when the air flowing from the instrument panel vents has a temperature of 7⁰C or lower.

Setting on Climatronic “LO”.

Setting on A/C system “AC” on; “max”; “cold”.

Note

With all complaints marked with *. Refer to → Chapter „Pressures, Checking“.

Total cooling system failure. *

Insufficient cooling performance at all vehicles speeds or engine speeds. *

None or insufficient cooling after driving a few miles. *

A/C compressor, A/C Clutch -N25- or A/C Compressor Regulator Valve -N280- are switched off by A/C Refrigerant Low Pressure Switch -F73-, A/C Refrigerant High Pressure Switch -F118-, A/C Pressure Switch -F129- or by A/C Control Head -E87- or Climatronic Control Module -J255- due to excessive or insufficient pressure. *

None or sharp decrease in fresh-air supply after driving several miles (evaporator iced up). *

From these, the following complaints may also occur:

The A/C compressor makes noises

–	Re-tighten compressor securing bolts and compressor bracket using a torque wrench.

–	Check routing of refrigerant lines; they must not touch other components and must not be subject to strain (align if necessary).

Noise (refrigerant hammer) occurring immediately after switching on air conditioner and/or when cornering or braking:

–	Discharge, evacuate and charge refrigerant circuit (too much refrigerant in circuit).

Note

Too much refrigerant oil in the circuit could also cause this problem. This could occur if the amount of refrigerant oil was not adjusted when replacing the A/C compressor. If this occurs, flush the refrigerant circuit with refrigerant R134a. Refer to → Chapter „Refrigerant Circuit, Flushing (Cleaning) with Refrigerant R134a“.

Drain the refrigerant from the A/C compressor. To facilitate this, the ribbed belt pulley or magnetic clutch plate on the A/C compressor should be rotated by hand. After flushing, the entire quantity of refrigerant oil specified by vehicle-specific repair manual should be added to the refrigerant circuit (50 grams directly in the A/C compressor).

Water sprays out of vents (in dash panel or footwell) although air conditioning system is otherwise functioning properly:

–	Check proper routing of condensate drain; it must not be crushed or kinked.

–	Check condensation drain valve, it must not be clogged by wax or underbody sealant and must open and close properly.

–	Check plenum chamber cover; it must not be damaged and must be properly installed (to stop water running into evaporator).

–	Check water drains in plenum chamber; they must not be blocked (e.g. by leaves).

Test Requirements

Note The A/C system is functioning correctly when the air flowing from the instrument panel vents has a temperature of 70C or lower. ...

Odor from the Heater and A/C Unit

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Other materials:

Physical Principles
The four known states of water also apply to air conditioning system refrigerants. 1 - gaseous (invisible) 2 - vapor 3 - fluid 4&nbs ...

Introduction
This chapter contains information on the following subjects: → Indicator lamp → Description of the central locking system → Locking and unlocking the vehicle from the outside → Locking and unlocking the vehicle from the inside → SAFELOCK mechanism &nb ...

Refrigerant R134a Vapor Pressure Table
The vapor pressure table for every refrigerant is published in literature for refrigeration system engineers. This table makes it possible to determine the vapor pressure acting on the column of liquid in a vessel if the temperature of the vessel is know ...