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Old 02-06-2019, 03:08 PM   #164
Graphite Dave
Dave Orton
Join Date: Dec 2007
Location: Occidental, Ca.
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Default Re: Orton DIY Transit

Did a test of my method of staying warm at night. Do not want a Espar due to the noise which is not compatible with city street parking or my sleeping.

Installation information:

Van is a 148" WB high roof Transit. About same interior length and width of a 144" WB Sprinter but 5" taller inside. Van has a slider door window and two back windows that were covered with Reflectix. There is a 27" wide sleeping platform at the back of the van with two REI 25" x 70" x 2 1/2" self inflating camp pads for a "mattress". Use a zero degree sleeping bag on top of the camp pads. Platform is surrounded by a insulated tent. Two layers of cloth with 1/2" Thinsulate between the layers. Back curtain is between the platform and the back doors that goes from the ceiling to two inches below the platform. Front curtain is in 3 parts to allow in/out entry and it closes off the front of the sleeping platform. There is a $30 1" x 50" x 18" Zonetech car back seat heating pad placed between the two self inflating camp pads. The Zonetech has two heat settings of 33 watts or 45 watts. Only used the 33 watt setting for the test. Initially I placed the Zonetech on top of both self inflating camp pads. That proved too be to hot so moved the heating pad between the two camp pads which solved that problem. Zonetech replaced the $100 Electro-Warmth bunk heating pad that I initially used. Two of the Electro-Warmth pads failed so I looked for a better solution. No curtain behind the front seats to wall off the cab or cab window covers. Van is insulated with polyiso, closed cell foam and Reflectix with air gap. Refrigerator was not running. The van normally uses 1% of the SOC overnight due to numerous small loads. So 1% of SOC used is not due to the heating pad.


Used a portable digital temperature gage for inside and outside the tent temperature readings. Used the Transit dash temperature to determine the outside the van temperature. Have a Magnum remote to give me the 255 amp-hr house battery state-of-charge. Started test at 100% SOC. Wore a balaclava to keep my head warm.


Time, inside tent temp., outside tent in van temp., outside van, SOC

8:00 PM, 48, 48, 39, 100

10:30 PM, 48, 48, 37, 98

12:30 AM, 46, 47, 36, 96

3:00 AM, 46, 46, 37, 95

6:00 AM, 43, 43, 36, 93

What was learned:

1. The inside the van tent idea was useless. Still hard for me to believe that it does not retain any of the body or heating pad heat inside the tent but obviously it does not.

2. Zonetech heating pad works very well. "Mattress" is very comfortable and heat level on low is about right.

3. The van insulation works. Kept inside van 7 to 9 degrees above outside temperature all night. As expected the interior temperature slowly decreased toward the outside the van temperature.

4. The seat heating pad used 6% or about 15.3 amp-hr of the house 255 amp-hr battery capacity. Easily back to 100% SOC before noon with the 300 watt solar panel power.

Next test will be determining if using the 1000 watt Magnum inverter to keep 6 gallons of water in the uninsulated shower water tank at 95 degrees is useful at night. The radiation from the tank and the 15% inefficiency of the inverter will add heat to the van interior. Will that be useful and how much house battery capacity will be used?

Do not have any difficulty warming the van in the morning. I can start the gas engine with the remote start and let it idle before getting out of bed. Dash controls set to deliver heat and the vehicle powered inverter is set to power the 750 watt electric baseboard heater in back of van.
Sold 2008 diesel NCV3 144" WB high roof DIY conversion
2015 gas Ecoboost Transit 148" WB high roof conversion

Web Site:

U-Tube Video:

Last edited by Graphite Dave; 02-06-2019 at 04:19 PM.
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