How to calculate gas consumption in your RV

Without gas, not much works in an RV. In summer the refrigerator runs all day and night and the barbecue is fired up regularly; in winter the heater runs at full throttle. How long your gas supplies last can vary considerably depending on the time of year and holiday destination. Read how to calculate the gas consumption in your RV in the Truma guide.

Calculating gas requirements in five steps

To calculate your personal gas requirements, for example, on a summer's day, proceed as follows:

  1. Write down what gas-operated appliances you use on one day (e.g. refrigerator, water heater, cooker).
  2. Add how long the appliances are used per day (e.g. water heater: 30 minutes, cooker: 60 minutes)
  3. If you know the gas consumption of an appliance per hour (you’ll find this in the operating instructions), calculate how much gas is consumed on one day in relation to the operating time (e.g. water heater consumption: 120 g/h if operated for 30 minutes per day: 120 : 60 x 30 = 60 g)
  4. Add together the gas consumption of all appliances and this gives you the average daily consumption in summer.
  5. If you now want to know how long a 9 kg gas cylinder will last, continue calculating. With consumption of 400 g gas per day, divide the total weight of the gas by the daily consumption: 9000 : 400 = 22.5. In other words, your 9 kg gas cylinder will last for about 22 days.

To calculate gas consumption exactly for autumn or winter, repeat the calculation for the gas consumption and include the running time of the heater. Remember that the heater consumes more or less gas depending on the setting.

Gas requirements dependent on external circumstances

Whether you need a lot of gas or can manage with less depends on the weather and your holiday destination but also on other factors, such as:

  • The size and insulation of the motor home
  • The number or persons travelling,
  • The energy efficiency of the appliances that run on gas,
  • The daily usage time of gas-operated appliances,
  • Your personal temperature preference.

Gas consumption of some appliances in the motor home

In winter, a motor home heater set at full output consumes most gas. Here are a few guiding values for the gas consumption of important appliances in the motor home:

  • Heater (150 – 500 g/h)
  • Boiler (approx. 120 g/h)
  • Stove/cooker (100 – 160 g/h)
  • Oven (80 – 120 g/h)
  • BBQ (300 – 400 g/h)
  • Refrigerator (14 – 20 g/h)

Checking your gas supplies

To know how much gas you have actually consumed, you can weigh your gas cylinders. The weight of an empty cylinder is engraved as tare weight. With an empty 9 kg cylinder, this is slightly more than 9 kilograms. In other words, a full 9 kg cylinder weighs approximately 18 kilograms. If you deduct the weight shown on the scale from the weight of the full cylinder, you see your gas consumption and know how much gas is left in the cylinder.

If you don’t have a scale handy or don’t want to lift heavy gas cylinders, you can use a filling level indicator.

Using ultrasound, the LevelCheck from Truma shows whether there is gas within the measuring range.

Simply hold it at a 90-degree angle to a steel or aluminium gas cylinder.

Tips: How to save gas

To make your gas cylinders last as long as possible, try to reduce gas consumption in the motor home. These tips may help you:

In summer, don’t leave the fridge door open unnecessarily when you’re putting something in or taking something out.

  • Never allow your RV to cool completely. Set the heater to a low setting when you leave the vehicle. If you do this, the heater doesn't have to run at full throttle to heat the space when you return.
  • Ventilate regularly, also in winter. Open windows completely for a few minutes and then close them again. Periodic ventilation prevents the surfaces from cooling completely.
  • A lot of heating energy is lost at thermal bridges. With insulating mats for the cabin, for example, you prevent heat loss and save gas.