Auxiliary heating – auxiliary heaters and separate systems – D3/4

The diesel versions of the Land Rover Discovery 3 & 4 and the RRS are mostly equipped with a diesel-powered auxiliary heater (Webasto Thermo Top) to quickly bring the engine up to operating temperature even at low temperatures. This auxiliary heater can be used as a “parking heater”. Whereby it is rather a light variant and not a full-fledged parking heater, because the maximum switch-on time is limited! However, it is usually sufficient to preheat the interior and to get the windows free of ice.

The advantage of a water heater is that it preheats the engine and thus enables engine-friendly operation at cold temperatures. The disadvantage of a water heater is that it consumes more energy (especially electricity) and usually cannot be operated permanently. The auxiliary heater, which is installed anyway, is such a water heater, but its running time is quite limited. The advantage of an air heater is that it directly heats the air inside the car, so it starts much faster. In addition, no pumps are necessary for this, only small energy-saving fans. Thus also a longer operation is possible, as long as the battery gives this.

The use of the auxiliary heater is therefore not a real parking heater! It cannot be used over a longer period, like a whole night*. It can be switched on only by call (radio or touch screen) for a certain period, in which the auxiliary heater heats up the car. This solution is for many absolutely sufficient and a really favorable alternative – in particular since it is usually eh installed.

By the way, the same applies to the “parking heater” available ex works in the Discovery 4. This is also not a permanent heater. This works like our upgrade kit for the Discovery 3, but with the difference that there is a timer with 3 programmable times here.

So what are the options now if you are looking for a parking heater function:

So what are the options now if you are looking for a parking heater function:

• Activation of the anyway installed auxiliary heater in the diesel and use as a parking heater.
  • cheap
  • is sufficient for everyday use (preheating the car in winter, getting the windows free of ice)
• Installation of a water parking heater
  • Recommended if you need longer heating times than the auxiliary heater allows*.
  • Multiple activations are possible via additional modules, provided that the battery voltage is sufficient.
• Installation of an air parking heater
  • Interesting if the interior is to be heated for longer periods and if engine preheating is not so important.
  • Can of course also be combined with a water heater or with the anyway installed auxiliary heater.

*Note: A parking heater runs only as long as there is enough energy available. To avoid that the battery voltage drops too much, the (water) heaters usually switch off after about 120min (30min with the original LR auxiliary heater). This can be avoided by starting the heater several times, but then an alternative power supply should be available in order not to endanger the starting process. Air heaters have longer heating times due to the lower energy consumption (see motorhome use), but are also dependent on the battery voltage.

In the Discovery 4 you can unlock the auxiliary heater via a programming (e.g. with the IID tool). Then you can operate the auxiliary heater via the touch screen display and program the timer there.

If you also want to switch on the auxiliary heater via remote control, the remote control module must be retrofitted and also programmed. Then the auxiliary heater can also be activated via it.

As an alternative to the original remote control, you can also use a third-party control such as the Bell control. With this you can also activate the auxiliary heater via cell phone, but a GSM card must be inserted in the Bell system.

As an alternative to the original remote control, you can also work with a third-party control such as the Bell control. With this you can also activate the auxiliary heater via cell phone, but a GSM card must be inserted in the Bell system.

In addition, an IPCU module is necessary for the warm air to enter the passenger compartment. Otherwise, the auxiliary heater is started, but the flaps of the ventilation are not open and the fan does not start. Thus, the engine gets warm, but the heat is not delivered to the interior.

The activation of the auxiliary heater is then always done via the remote control or the cell phone depending on which third-party solution is selected. (e.g. Bell)
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