Rickster22
New member
Hi! I have just acquired a 2004 Sprinter (140 wb, high roof) and will be converting it to a camping vehicle. I have been getting lots of invaluable info from this site by lurking and reading. However I now have an issue that I can’t find a solution for that way, so I thought I would jump in and ask.
The vehicle is high mileage (around 300,000 miles), and has had a fairly rough life in Alberta Canada as a commercial vehicle. At one time it appears to have had a rear heater option, but it was “de-installed” by cutting the coolant tubes underneath the van, and by hacking away (it seems, anyway) at the plumbing. One of the things they seem to have done is completely remove the heater control valve, and (I think) patched together the coolant line from the water pump that used to go into the heater control valve with the line that went out of the valve to the heater unit. The result is that it is perpetually blowing hot air, so I am getting no noticeable air conditioning (found that out after replacing the AC compressor, which was broken, and found I was still was not getting any cold air in the cabin!). The mounting bracket and electrical connection for the heater control valve are still there.
So, I have ordered a replacement heater control valve (the Bosch OEM unit with three hose barbs, which is for vehicles without the rear heater….which mine sort of is…! ). My problem is hooking it up, since there is not one in place to copy, and the plumbing may have been modified, so the hoses may not be stock. To add to the plumbing issues, when I got the van, the Espar heater was leaking coolant, so we have done our own plumbing mods to that and bypassed the Espar. We have also had to replace the electric recirculating coolant pump, as it was not working.
The shop manual doesn’t seem to be too informative about the heater control valve. I would kill for a plumbing schematic, but it seems there isn’t one, as there have been a couple of other people on the forum that asked, but with no success…). The best info I can get on hooking it up appears to be from the 2004 Sprinter parts catalog. They have an exploded picture there (Figure 24-260 on page 403 of the PDF) that provides a couple of hints.
On that diagram, it appears that the pump orients with the side that has the 2 barbs facing the rear of the vehicle, and the side with the single barb facing the front. On the front, there is a rubber hose (#16 on the diagram, Mopar part 05124844AA). I believe that that hose is connecting to the metal tube that is bringing coolant up from the water pump. However, the diagram seem confused, in that it also shows another hose going to the same barb on the valve. That is #18 (05125981AA ) and #1 (05124858AA) on the diagram. I am thinking that that is a “variant” for vehicles with the Espar, since the description of #18 is “flexible exhast, supplementary heater”. Since I have the Espar cut out, I am thinking that I want to configure the input directly from the water pump via hose #16.
On the other side of the valve, there are the two hose barbs. The top one appears to go directly to the heater box via hose #6 (mopar 05124846AA). I assume that is the feed in to the heater box when diverting hot coolant in. I guess my main mystery is the bottom hose barb. The parts diagram does not indicate anything attaching to it. My only guess is that it might connect to the recirculating electric coolant pump (the one we replaced). It seems to make sense that if we are not sending hot coolant to the heater core, that we would divert it directly to the coolant pump.
The same parts explosion diagram seems to indicate two variants for the connection to the recirculating pump. One seems to be via hoses #17 (05124848AA) and #8 (05124644AA). The other variant seems to be via hose #10 (05124842AA). I am guessing that this also might be for with and without the ESPAR? I have googled the part number, and #10 seems to be described as being related to the “heater booster”. But I also googled 05124848AA and it is described as TUBE Heater..”Heater Booster”. So perhaps I am wrong there.
On my van currently, one side of the recirculating electric coolant pump appears to be connected to the intake manifold/EGR valve, and the other side is currently attached directly into the heater box (but I can’t see precisely where it is attached). I assume that is an output from the heater box going into the coolant pump.
So, I think my current situation with the van is that coolant is coming from the water pump, directly to the heater box, then is going from the heater box to the recirculating coolant pump, and then to the intake manifold/EGR valve. So, my guess is that I should inset the new heater control valve with the existing line from the water pump as its input, and then the top output from the control valve going to the heater box via the existing hose ( the one that is currently spliced directly to the water pump hose). Then, it seems to make sense that there should be two lines going into the recirculating pump. One directly from the Heater control valve, for the case where coolant is being diverted by the valve away from the heater, and the other from the heater box output, for the case where the coolant is being sent to the heater box. So I think that I need to add a Y connection that combines those two, and connects the output of the Y to the coolant pump input.
Naturally, I am not naïve enough to believe that that will be the end of it! I am fully expecting to find that there are problems in the Climate Control Module, and expect I will have to send that out for a rebuild. But if the plumbing is not hooked up correctly, I won’t get very far, so I want to get that done first. If anyone has any thoughts about the correctness of my assumptions and current plan, I would really appreciate it!
Rick
The vehicle is high mileage (around 300,000 miles), and has had a fairly rough life in Alberta Canada as a commercial vehicle. At one time it appears to have had a rear heater option, but it was “de-installed” by cutting the coolant tubes underneath the van, and by hacking away (it seems, anyway) at the plumbing. One of the things they seem to have done is completely remove the heater control valve, and (I think) patched together the coolant line from the water pump that used to go into the heater control valve with the line that went out of the valve to the heater unit. The result is that it is perpetually blowing hot air, so I am getting no noticeable air conditioning (found that out after replacing the AC compressor, which was broken, and found I was still was not getting any cold air in the cabin!). The mounting bracket and electrical connection for the heater control valve are still there.
So, I have ordered a replacement heater control valve (the Bosch OEM unit with three hose barbs, which is for vehicles without the rear heater….which mine sort of is…! ). My problem is hooking it up, since there is not one in place to copy, and the plumbing may have been modified, so the hoses may not be stock. To add to the plumbing issues, when I got the van, the Espar heater was leaking coolant, so we have done our own plumbing mods to that and bypassed the Espar. We have also had to replace the electric recirculating coolant pump, as it was not working.
The shop manual doesn’t seem to be too informative about the heater control valve. I would kill for a plumbing schematic, but it seems there isn’t one, as there have been a couple of other people on the forum that asked, but with no success…). The best info I can get on hooking it up appears to be from the 2004 Sprinter parts catalog. They have an exploded picture there (Figure 24-260 on page 403 of the PDF) that provides a couple of hints.
On that diagram, it appears that the pump orients with the side that has the 2 barbs facing the rear of the vehicle, and the side with the single barb facing the front. On the front, there is a rubber hose (#16 on the diagram, Mopar part 05124844AA). I believe that that hose is connecting to the metal tube that is bringing coolant up from the water pump. However, the diagram seem confused, in that it also shows another hose going to the same barb on the valve. That is #18 (05125981AA ) and #1 (05124858AA) on the diagram. I am thinking that that is a “variant” for vehicles with the Espar, since the description of #18 is “flexible exhast, supplementary heater”. Since I have the Espar cut out, I am thinking that I want to configure the input directly from the water pump via hose #16.
On the other side of the valve, there are the two hose barbs. The top one appears to go directly to the heater box via hose #6 (mopar 05124846AA). I assume that is the feed in to the heater box when diverting hot coolant in. I guess my main mystery is the bottom hose barb. The parts diagram does not indicate anything attaching to it. My only guess is that it might connect to the recirculating electric coolant pump (the one we replaced). It seems to make sense that if we are not sending hot coolant to the heater core, that we would divert it directly to the coolant pump.
The same parts explosion diagram seems to indicate two variants for the connection to the recirculating pump. One seems to be via hoses #17 (05124848AA) and #8 (05124644AA). The other variant seems to be via hose #10 (05124842AA). I am guessing that this also might be for with and without the ESPAR? I have googled the part number, and #10 seems to be described as being related to the “heater booster”. But I also googled 05124848AA and it is described as TUBE Heater..”Heater Booster”. So perhaps I am wrong there.
On my van currently, one side of the recirculating electric coolant pump appears to be connected to the intake manifold/EGR valve, and the other side is currently attached directly into the heater box (but I can’t see precisely where it is attached). I assume that is an output from the heater box going into the coolant pump.
So, I think my current situation with the van is that coolant is coming from the water pump, directly to the heater box, then is going from the heater box to the recirculating coolant pump, and then to the intake manifold/EGR valve. So, my guess is that I should inset the new heater control valve with the existing line from the water pump as its input, and then the top output from the control valve going to the heater box via the existing hose ( the one that is currently spliced directly to the water pump hose). Then, it seems to make sense that there should be two lines going into the recirculating pump. One directly from the Heater control valve, for the case where coolant is being diverted by the valve away from the heater, and the other from the heater box output, for the case where the coolant is being sent to the heater box. So I think that I need to add a Y connection that combines those two, and connects the output of the Y to the coolant pump input.
Naturally, I am not naïve enough to believe that that will be the end of it! I am fully expecting to find that there are problems in the Climate Control Module, and expect I will have to send that out for a rebuild. But if the plumbing is not hooked up correctly, I won’t get very far, so I want to get that done first. If anyone has any thoughts about the correctness of my assumptions and current plan, I would really appreciate it!
Rick