Heater sizing

[86Scotty]

I have a CDH (Chinese diesel heater) in my van that is supposedly rated 5kw. It is also supposed to auto adjust for high altitude. So far performance has been marginal.

I recently scored a Webasto Airtop 2000 which is a smaller 2kw unit.

I'm curious how many van owners with pop tops are running an Espar D2 (2kw) or a Webasto Airtop 2000 (2kw) and whether you think it's enough.

I might swap the CDH for the Webasto.

[Youngster]

A 2kw at full power is good to about 30*, top popped, with the heater output blowing in the direction that will allow the heat to get up into the poptop. Downstairs will still be toasty. I've used a 2kw, full power, down to 15* top popped with a decent sleeping bag and was a little chilly but could sleep reasonably. I have gotten more poptop efficiency out of my 2kw by lining the sides of my poptop with these (a bit cheaper back in the day).

Strictly mountain or a lot of eastern winter camping, use 5kw.

[dhally]

We have an RB fixed high top, Propex 2 KW which is about 6800 btu/hr. It is OK down to about 20 F but runs about 80 percent of the time.

[posplayr]

Originally Posted by 86Scotty

I have a CDH (Chinese diesel heater) in my van that is supposedly rated 5kw. It is also supposed to auto adjust for high altitude. So far performance has been marginal.

I recently scored a Webasto Airtop 2000 which is a smaller 2kw unit.

I'm curious how many van owners with pop tops are running an Espar D2 (2kw) or a Webasto Airtop 2000 (2kw) and whether you think it's enough.

I might swap the CDH for the Webasto.

One thing to be aware of if you want to test the maximum heating of a diesel heater (assuming it is like my petrol heater ) if you let the thermostat be in the heat lower area and the temp hits the set point , the heater will throttle back the pump pulse rate.

I've tried to test my unit during the day and It acted very wonky unless I put the thermostat outside of the van. Then it would run full out trying to get to a high setpoint.

In a van with pop top and a lot of heat being lost through the top, it is not clear where the best place for a thermostat is.

[Big_ern_101]

-CCV Insulated pop top
-Fully insulated RB Econoline WINDOW VAN
-5k BTU Chinese Diesel Heater
-CHD is mounted in rear passenger side, behind the wheelwell
-One duct points up to the roof of the van
-One duct points down at the floor, about in the middle of the van, by the passenger side barn doors
-In 20°F ambient, I see 70s downstairs if I want to and 62-64 upstairs. Runs on high probably 20% of the time an idles back the rest of the time, running an Afterburner controller.