Romer
Adventurer
Still loving the Karavan after 7 years of use. It is nice to have a Local Dealer in the US. However the drive from Denver to Ohio is to far for service/repairs. As such I have gone through the system piece by piece to understand it
I took it to Moab for a week. I had checked out everything but the water system as it was supposed to be in the 20's (deg F) at home the night before I left. So I filled the tanks the next morning and left for Utah
I blow the system out with compressed air after draining the tanks before winter. This year in Denver it was below - 20 deg F for several days at a time and I believe up to a week
I had two Problems
1) The water filter had cracked on the Potable line. It is installed under the seat in the cab. This is from the tank labeled Drinking (potable) and provides cold to both the inside and outside sink. So when I ran it in Moab, I had a water leak coming out the cracks. It was easily fixed by replacing the filter. Then I decided to remove the filter altogether and attach it to my fill hose. That will do the same thing and I can fill both tanks with the filter setup.
2) I turned on the Hot at the sink and green liquid came out. I tracked this down to lines in the Heat Exchanger cracked mixing the Green Glycol Coolant with water, I was able to get a replacement Heat Exchanger from Australia in 11 days to my house. It is worth noting that the tank providing the Hot also provides the cold to both showers and the toilet. This allows the Australians to pull water from a stream (Non potable) in the outback where this was designed to operate.
A key item for the Karavan Plumbing is understanding how the Potable and Non Potabile tanks are setup and routed. Since I fill both tanks at home, both tanks for me are really potable
I developed the below diagram of my plumbing system with part numbers and installed pictures
Note the Glycol is heated by the Diesel Webasto Thermo Top that also has the pump for the Glycol. The Glycol is heated and then runs into the Heat Exchanger where the coiled lines run next to water lines and heat the water. My unit came with an air heater run off the Hot water Glycol in the cab. I found it inadequate and previously replaced it with a Diesel unit that has been awesome. Since I had to fully drain the Glycol to replace the Heat Exchanger, I took the Opportunity to remove the in cabin Glycol based air heater
Just a few photos on the repair
After removing the cover plate, this is the Hot Water System. A strainer in the Top left feeding into the Water Pump (Par Max) just below it. This feeds the Heat Exchanger and the Cold taps for the showers and the toilet. The Bottom left has the Webasto Thermo Top which pumps and heats the Glycol from the tank in the middle. The heat Exchanger is in the bottom right
removing the Heat Exchanger
The replacement unit before inserting it into the Red cover
all buttoned up with the cover plate back in place. I have Duct tape as a temporary cover for where the Glycol hoses went into the cab for the air heater
Oh and my Water filter setup. Now both tanks get filtered water and one less component to worry about failing or having to replace periodically. The cover is off the Hot Water heater as I was filling it to first validate the system worked and also flush the lines to remove any residual Glycol
Last to address the cause of the problem. I keep the Karavan in a detached Garage. It isn't Insulated or heated. My main garage with my vehicles and workshop is attached and never gets below freezing. So this past week I insulated the garage and will use a small heater to keep it above freezing or at least not much below. I will continue to blow the system out and will monitor the temperature in that garage to see if I need to add a second heater next winter.
I have no plans to drywall this garage. Again, it isn't my main garage and I only use it to keep the Karvan and do maintenance on the lawn equipment in Spring-fall. This is my main garage. My wife also gets to park there, but she was out shopping when I took the picture
I took it to Moab for a week. I had checked out everything but the water system as it was supposed to be in the 20's (deg F) at home the night before I left. So I filled the tanks the next morning and left for Utah
I blow the system out with compressed air after draining the tanks before winter. This year in Denver it was below - 20 deg F for several days at a time and I believe up to a week
I had two Problems
1) The water filter had cracked on the Potable line. It is installed under the seat in the cab. This is from the tank labeled Drinking (potable) and provides cold to both the inside and outside sink. So when I ran it in Moab, I had a water leak coming out the cracks. It was easily fixed by replacing the filter. Then I decided to remove the filter altogether and attach it to my fill hose. That will do the same thing and I can fill both tanks with the filter setup.
2) I turned on the Hot at the sink and green liquid came out. I tracked this down to lines in the Heat Exchanger cracked mixing the Green Glycol Coolant with water, I was able to get a replacement Heat Exchanger from Australia in 11 days to my house. It is worth noting that the tank providing the Hot also provides the cold to both showers and the toilet. This allows the Australians to pull water from a stream (Non potable) in the outback where this was designed to operate.
A key item for the Karavan Plumbing is understanding how the Potable and Non Potabile tanks are setup and routed. Since I fill both tanks at home, both tanks for me are really potable
I developed the below diagram of my plumbing system with part numbers and installed pictures
Note the Glycol is heated by the Diesel Webasto Thermo Top that also has the pump for the Glycol. The Glycol is heated and then runs into the Heat Exchanger where the coiled lines run next to water lines and heat the water. My unit came with an air heater run off the Hot water Glycol in the cab. I found it inadequate and previously replaced it with a Diesel unit that has been awesome. Since I had to fully drain the Glycol to replace the Heat Exchanger, I took the Opportunity to remove the in cabin Glycol based air heater
Just a few photos on the repair
After removing the cover plate, this is the Hot Water System. A strainer in the Top left feeding into the Water Pump (Par Max) just below it. This feeds the Heat Exchanger and the Cold taps for the showers and the toilet. The Bottom left has the Webasto Thermo Top which pumps and heats the Glycol from the tank in the middle. The heat Exchanger is in the bottom right
removing the Heat Exchanger
The replacement unit before inserting it into the Red cover
all buttoned up with the cover plate back in place. I have Duct tape as a temporary cover for where the Glycol hoses went into the cab for the air heater
Oh and my Water filter setup. Now both tanks get filtered water and one less component to worry about failing or having to replace periodically. The cover is off the Hot Water heater as I was filling it to first validate the system worked and also flush the lines to remove any residual Glycol
Last to address the cause of the problem. I keep the Karavan in a detached Garage. It isn't Insulated or heated. My main garage with my vehicles and workshop is attached and never gets below freezing. So this past week I insulated the garage and will use a small heater to keep it above freezing or at least not much below. I will continue to blow the system out and will monitor the temperature in that garage to see if I need to add a second heater next winter.
I have no plans to drywall this garage. Again, it isn't my main garage and I only use it to keep the Karvan and do maintenance on the lawn equipment in Spring-fall. This is my main garage. My wife also gets to park there, but she was out shopping when I took the picture
