Monday 21 October 2013

Insights from Grade 3 Cold Chamber Testing: Motorhome & Caravan Winterisation

TankBlanket:  Winterisation that Works

Motorhome & Caravan Winterisation: Insights from Grade 3 Cold Chamber Testing from TankBlanket: The Tank Heater our last blog we presented the detail behind Grade 3, the British standard for heating and insulation and explained that a motorhome accredited with Grade 3 will keep you warm throughout the winter months. The scope of Grade 3 excludes the fresh and waste water system and a vehicle with Grade 3 accreditation offers no protection against your water system freezing in sub zero temperatures.

This Blog concentrates on winterisation and the insights gleamed from our recent experience with cold chamber testing.

Most internet and periodical articles treat winterisation as preparing your vehicle for storage, but we define it, as a motorhome that can be used during the winter months with a water system that does not freeze.

Recently we were involved in a cold chamber Grade 3 test for a Panel Van conversion which threw up some interesting insights about winterisation and the impact of freezing conditions on the fresh and waste water system.

During a Grade 3 test the vehicle is soaked overnight to achieve a temperature of -15 °C throughout. Using infrared photography we established that the really cold spots on a typical panel van conversion were:

1.    Inside bed boxes.

2.    The ‘D’ posts or rear corners of the vehicle.

3.    The middle of the rear doors.

4.    The internal surfaces of the wheel arches, which were particularly cold.

5.    Cab foot wells.

6.    Cab windscreen and side windows.
Another interesting point was the position of the dump valve for the water heater. If this is located away from the heater, which generates its own ‘warm area’, then the contents of the water heater can potentially be ‘dumped’ early.

Under Grade 3 test conditions the test vehicle is given a period of up to four hours to reach 20°C from a start point of -15°C. An important, but overlooked fact before the test was the effect airflow had on the ability of the heating system to warm the vehicle throughout.
To improve the points above the following corrective actions were taken:
              i.        The blown air ducting was re-routed through the bed boxes. Small holes were made in the ducting to bleed warm air in to the bed box.

             ii.        The insulation of the ‘D’ posts was substantially improved.

            iii.        A removable studded sealing/insulation strip was added to the centre of the rear door, running from top to bottom.

            iv.        The wheel arches were insulated with WheelarchBlankets. These are one of seven modules of The TankBlanket System, the water tank heater.

             v.        The flow heated blown air was improved in to the cab foot well.

            vi.        Silver windscreen guards were installed to improve the windscreen and side window insulation.

           vii.        The location of the dump valve was moved to a position as close to the water heater to overcome the possibility of its contents being purged early.
To improve the efficiency of the blown air heating system and its effectiveness to achieve a homogenous temperature throughout the vehicle the pathway of the blown air ducting pipework was re-designed.

Drafts can be a problem and in our experience they originate from two sources, the free flowing ventilation and build quality. Caution is required here and any draft from free flowing ventilation either in the roof or floor is best left alone. Those drafts created from build quality are a different matter and we recommend contacting your Dealer or Manufacturer to remedy these issues.
 For winterisation tips follow:

For winterisation tips from around the web follow:

In our next blog, Motorhome winterisation will be discussed in detail and the impact of The TankBlanket System, the water tank heater.

The water tank heater


Wednesday 9 October 2013

Grade 3 Explained: Motorhome & Caravan Winterisation

TankBlanket:  Winterisation that Works

TankBlanket: The Water Heater presents:

Motorhome & Caravan  Winterisation: Grade 3 Explained!
As I write, the October NEC Motorhome and Caravan Show is a matter of days away and with the economy showing signs of strengthening, expectations are high for a good Show.

At this point it seems 2014 will be defined by models that are marketed as energy efficient and winterised. This blog will discuss Grade 3 and winterisation.

The Consumer will be bombarded during the October show  with stickers displayed on product and brochures that declare 'this motorhome is Grade 3 accredited' and is a ‘winterised’ vehicle that can be used ‘all year round’. So what is Grade 3 and what does ‘winterisation’ mean?

Simply, Grade 3 is a British standard for heating and insulation while ‘winterisation’ is a term open to a plethora of interpretation, but for this blog, it is taken to mean a motorhome that can be used in freezing conditions with free flowing fresh and waste water.

Grade 3 emanates from the British standard BS EN 1646-1:2012 titled ‘Leisure accommodation vehicles – Motor caravans part 1: Habitation requirements relating to health and safety’.  Within section 9 of this standard is the detail relating to three levels of motor caravan heating. These are:
Grade 1: No heating.

Grade 2:  When the outside temperature is 0°C the internal temperature must be held at an average of at least 20 °C for a defined period of time.

Grade 3: When the outside temperature is -15°C the internal temperature must be held at an average of at least 20 °C for a defined period of time.

The test has to be performed under controlled conditions and is subject to certain criteria so results can be reproduced and compared with statistical integrity. The standard states that the test should be performed in a cold chamber with temperature probes located at specific points.

The test is subject to four time based criteria. These are:

Phase 1: The vehicle is soaked a in cold chamber for at least 10 hours to achieve a temperature of 0 °C or -15 °C throughout, depending whether it is a grade 2 or 3 test.

Phase 2: Upon reaching its soak temperature the habitation heating system is switched on and the vehicle is given up to 2 hours or 4 hours to achieve an internal temperature of 20 °C, again, depending whether it is a grade 2 or 3 test.

Phases 3 & 4: Once the internal temperature of 20 °C has been achieved a 1 hour stabilizing period commences before monitoring of the thermal energy consumption takes place.

 This is the important statement for those wishing to use their vehicle throughout the year:

The standard states that ‘precautions’ should be taken to ensure that the fresh water system can be charged at the end of the 1 hour stabilising period (phase 3) and operate while the external temperature is at -15 °C.

This means the business end of the test is performed with a dry vehicle and water is only added at the end of the one hour stabilising period, that is, when the vehicle's internal temperature is at 20°C.

If the vehicle under test achieves all of the above criteria then it is accredited as a Grade 3 Motorhome.

So, Grade 3 is a thermal insulation and heating standard. A motorhome with Grade 3 will keep you warm in freezing conditions but it will not provide you with free flowing fresh and waste water during sub zero temperatures.
So, who in the UK manufactures a genuinely ‘winterised’ motorhome, one that can be used all year round with confidence that the water system is not going to freeze up? Let's see what 2014 brings!

In our next blog, insights gained from cold chamber testing of TankBlanket, the water tank heater, will be discussed. So, why not follow us?
TankBlanket : The water tank heater

Friday 4 October 2013

Introduction to TankBlanket and Grade 3: Motorhome & Caravan Winterisation

TankBlanket: Winterisation that Works

 TankBlanket: The Water Tank Heater

Welcome to the first blog entry from TankBlanket, the water tank heater winterisation system for leisure and utility vehicles that has genuine providence to prove it works!

TankBlanket was developed in the USA as a winterisation system for RV vehicles and has been tested to -24 °C with units installed during 1991 still protecting  tanks today!

During 2014, the buzz word will be winterisation.

Currently, all the major manufacturers of Leisure vehicles plan to offer 'winter packs' on their 2014 model range and are scrambling to perform cold chamber tests to gain the Grade 3 European and British standard. Grade 3 only deals with heating and insulation, it does not cover the water system and its ability to deliver free flowing fresh and waste water in freezing conditions. It only assures that the vehicle is well insulated and the heating system can maintain a comfortable habitation temperature.
That’s where the TankBlanket system steps in. When installed correctly, the tank heater ensures that your fresh and waste water system delivers free flowing water in sub zero conditions.
The next blog will deal with grade 3 in more detail, so why not follow us?


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