Please check your SPAM folder for your order notification if you don't see it immediately after placing the order.
Toll free order line and fax: 888-250-8139

Vangon Articles - The water cooled Vanagon heater system


Search by SKU or Keyword

Vanagain on Facebook!

The water cooled Vanagon heater system

February 6, 2015 29 Comments HVAC Ken Wilford

The Vanagon Heaters:

The water cooled Vanagon has two awesome heaters that, if working properly, will fry you out of the van. They are what I want to discuss today.

Front Heater.

Your front heater is a critical safety device. I know you probably think of it as a comfort device but think back to a day when the outside temperature suddenly changes due to a rain storm. The inside of your windshield starts to fog up and you can’t see a thing. You reach to turn on your windshield defroster and it doesn’t work! Now you have to either pull over (safe) or keep someone wiping the windshield down with a towel while you drive (not as safe). It would be so much better if you just adjust the defroster lever, turn the blower fan on and everything works the way it should.

Front Blower Fan.

One key to the front heater working properly is the front blower fan. These can seize up over time. In a normal car everything that you would do, heat or A/C, would involve this fan. In the Vanagon, the A/C is not in the dash so you only use the blower fan mostly in the winter. This lets the shaft rust. The best way to prevent this is to use the fan frequently, even in the summer. Just turn it on, once a week, even if it is at the lowest speed, to keep it going. If your front fan is stopped and blowing the fuse it is probably the fan itself that has seized up. If it isn’t blowing the fuse you can try the switch in the dash as they can go bad and they don’t cost very much. You can also check your ground connections over above the fuse panel. They are a “star” connector that has multiple grounds coming into it. If the motor isn’t getting grounded then it won’t work. Clean the grounds and be sure that the ends of the spade connectors are making good contact (they can loose their crimp tension over time). If the fan works but only on the highest speed then your resistor inside the air box is bad (very rare).

Inside the box.

If you have determined that your blower fan is bad. Then you are going need a new fan and also a set of 10 blower fan clips. The plastic air box is actually sealed together by melted plastic tabs. When you open the box you have to break these tabs. However VW has provided places around the edge of the box for you to use metal clips to put the box back together. Be sure to order these whenever you are ordering a new blower fan as you will need them to get the job done. I always notify customers about this when they are ordering the fans.

Cleaning and seal repair.

While you could just pull the whole dash apart, change the fan and put everything back together, it is kind of a shame to not make things happy while you have everything apart. I always clean the inside of the plastic air box out and also wipe down the inside of the dash. A damp rag and some soapy water will work no problem. You can even spray down the inside of the dash with some scented disinfectant if you want that “new car” smell. The seals can be replaced easily. I use some air conditioning filter material (foam) that you can get from Home Depot. Just cut it to the size and shape of the old one, snap the plastic fastners apart clean out the old foam, put the new foam in place and snap it back together. It is that easy.

Front Heater Core.

Front Heater Cores are very robust and will last over 20 years. However everything has a lifespan and I am sure that most of these cores are reaching theirs. It would be the best PM to just replace this as well if you can afford it. If it is bad you will have to replace it. Smell it. Does it smell like antifreeze? Does it have crusty stuff around the edge? It is bad and must be replaced. The OE cores have been discontinued but we have custom made cores available if you find you need one.

Rear Heater.

The rear heater core is is much more prone to leaking. Usually you will smell a coolant smell when you turn it on. The good news is that the rear heater fans and resistors are usually bulletproof. So it is super rare to have a rear heater fan or resistor to actually be bad (I have never sold either of these in ten years).

Rear Heater Cover Removal

On Westies you can just loosen a couple of screws and the wooden cover comes right off. On 83-85 Vanagons without rear seat/beds are also easy. If you have an 86-91 Vanagon weekender with a rear bed it can be more tricky. The frame that goes around the front vent of the blower housing goes under it. In order to remove the housing cover you can either remove the rear seat (a real pain) or you can just cut the lower frame away from the blower housing. I use a blade from a hacksaw. Saw down on either side of the blower vent. It should only take a little cutting on each side to cut through the plastic. Once you do this and remove all of the screws you should be able to pull the cover straight up and off. Inspect the rear core in the same way you inspected the front one. If it is suspect replace it.

Rear Heater Valve

Sometimes the core is good but the valve is leaky. You should always replace the o-ring that seals the valve to the rear core. If the valve is bad it should be replaced as well. Sometimes the rear bleeder valve on the core can be leaky but a new one comes with the new rear core.

If you follow these guidelines you should have warm heat, with no smell and no leaks. Also fixing your seals in the front box it will help everything to work better as well. As always any parts or advice you might need feel free to email me.

Copyright Van-Again 2015


Nick B January 6, 2020

Hello, Brian Corcoran left the follow message in Spet of 2017, iit reads...Ken, I have used your advice for many of my '85 vanagon repairs. Currently, I am replacing the rear heater blower motor. I am having trouble getting the blower out of the plastic housing. I have it apart in three separate pieces, yet the blower will not slip out. Is there a special twist or should it just tap out? Thanks for all the great advice. I didn't see a reply and would like to know the same thing. Thanks

John October 22, 2018

I am trying to replace the blower switch (front heater) in my 87 Westfalia. I can't find a videos that would show how to do it, and nothing on the internet that would be in writing. Would you have any advice or direct me to something that I might be missing?

Ken Wilford October 4, 2017

It is trying to speak to you. It is telling you it is time to replace it with a new one. The grease is old and dried out. The bushing is probably getting rusty and starting to seize. Hitting the dash will only work for so long. It is time to do a new blower fan. Ken

Rick Pighini October 4, 2017

Hi Ken, I have a 1987 vanagon. Last winter once it got cold the front heater fan would not turn on. If I hit the dash it sometimes would. We just got 18" of snow and this morning my front fan would not turn on again. It worked every time I turned it on all summer and even yesterday. After I hit the dash like fonzy a few times it came on. I'm thinking it may just be dirty and cold weather gets it stuck, but I'm not sure. Towards the middle of last winter even hitting the dash would not turn it on, but once the weather warmed it came on every time. What do you think?

Brian Corcoran September 13, 2017

Oh boy, Just my luck. Stump the expert. LOL I have it apart an taping with a hammer does not free it. Although it will slide back & forth about 1/2 an inch. I will certainly let you know what I learn. Thanks for reading and responding so quickly.

Ken Wilford September 13, 2017

Brian, I am not sure. One of the few parts I have never replaced. I have done the rear cores, but never the fans as they are usually still good. I guess you will have to do it and then let me know how you do it. :-) It looks like you just remove the rear core, and split the housing in half, but there is probably a screw or two that I am not seeing. Ken

Brian Corcoran September 13, 2017

Ken, I have used your advice for many of my '85 vanagon repairs. Currently, I am replacing the rear heater blower motor. I am having trouble getting the blower out of the plastic housing. I have it apart in three separate pieces, yet the blower will not slip out. Is there a special twist or should it just tap out? Thanks for all the great advice.

Ken Wilford January 12, 2017

Here is the rear heater valves we sell. It has the lever so you can turn it on and off. Just let me know if we can you further. Ken

Ken Wilford January 12, 2017

We sell them. Just let me know. Ken

Cole January 11, 2017

Seems my fan motor is bad - it smokes when you turn the switch on... Any ideas on where to get a new fan?

Steve July 29, 2016

Hi Ken, hope this message finds you in good spirits, I got a 91 vanagon,carat, looked for the shut off switch/lever for that heater under the rear seat and couldn't find it. Is there not one there? can it cool down in these hot summer months? Heat r will it always be hot there. regards, Steve

Ken Wilford June 7, 2016

Bill, we are currently getting brand new front heater cores from Europe. They are made by JP Group in Denmark. Right now I am out of stock but I should have more very soon. My advice would be to order one now and then I will ship it to you as soon as it arrives as we are still getting limited stock on these. Here is a link to the product page Vanagon Front Heater Core

Bill Caviness May 26, 2016

you say you have available custom built front heater cores- I am need of one for an 1982 VW vanagon 1.6 diesel. Please tell me how i can get one.

Ken Wilford April 19, 2016

Chris, there are no sensors associated with the rear heater or even the front one for that matter. I think your issue is most likely a bad ground that is being effected by heat. I would check the connectors on the rear blower motor for corrosion and then trace the ground connection and test that as well. You should find your problem that way.

Ken Wilford April 19, 2016

Jimi, you have a hot air heating system that gets its heat from the exhaust system of the vanagon. This will generate some serious heat as the exhaust system can get to around 700 degrees F! The problem is that most of these systems suffer from neglect, leaking air ducts, improperly adjusted valves, etc. Your best investment in this area is to take your van to a VW specialist and have them evaluate your stock heating system and then repair and adjust it as needed. You will have heat and it will be the cheapest way to go about getting it in your air cooled Vanagon.

Jimi April 18, 2016

Hi, I have a 1982 Westfalia CampMobile. (going on two years now) I don't have any heat besides what the motor provides through the lower vent. Should I have a heater? I don't use the van during cold weather because I didn't know if this vehicle came with a heater or not. What would be the possible outlay of money to get one installed or working?

Ken Wilford March 2, 2016

Chris, the rear heater blower fan isn't hooked to anything in the fuel injection system or any type of coolant temp sensor. So it has to be an electrical issue. Most likely culprit would be either a faulty switch or a bad ground at the heater wiring under the rear seat. Something electrical is heating up and then failing when hot. My vote is the ground connection near the rear heater.

Chris Anderson February 28, 2016

Hi, Ken. Thank you for the great write-up. This helps a lot but I have a lingering issue with my rear heater that continues to confound me. When the van engine is cold the heater fan/blower works on all three speed settings (low to high). Once the engine warms up a little the rear heater blower does not work on any of the speeds. I've been trying to make sense of this and the only thing I can think of is the engine temp sensor that talks to the MAF during warm-up. Could these be connected? If you don't think so, is there anything else that you think could be causing this issue, i.e. bad resistor? Thanks in advance for considering my problem!

Tony Sudney December 5, 2015

Hey Ken Very late with this answer; Yes, had the rear heater core replaced about 1998, at that timke I could smell coolant in the van.. Tony Sudney

Ken Wilford September 29, 2015

Tony, I have been thinking about your problem for a while. Let me ask you a question: Have you had any work done on the rear heater under the back seat lately? Let me know. That plug on the alternator is for an old VW special tool that some dealers had back in the 80s. It is not used for anything else. Ken

Tony Sudney September 17, 2015

Hi Ken I'm the one with the low winter heat in my 1990 vanagan. During this past summer the heat gauge would come up to a little over 1/3 the way up the gauge. This past week one morning the temp. was down to 58 degrees, which is not really cold, again the heat gauge pointer did not come off the bottom bar, but, as the morning went on the temp moved over the 60 degree point and with it the heat gauge started to move upward. In several weeks as the fall moves in I will purchase from you a thermostat and o-ring/gasket and give it another shot... I'm also experiencing aq coolant leak from what appears somewhere on the front right cylinder. Sometimes it drips pretty fast, other times just a drip or two, then stops for weeks at a time. I know over time it will get worst, I check and get about 5 or 6 oil changes over a years time, I'm specifically looking for water in the oil, as of yet I find nothing. NOW, would it cause any problems if I should add a brand name stop leak to the coolant as a more or less band aid while I ponder a major solution.. On the alternator while looking toward the front of the vanagan on the right side rear I notice a three prong receptical, is this some kind of a test point.. Tony Sudney

Ken Wilford June 13, 2015

It would have to get really hot to kill the thermostat. Is there a problem with the low speed radiator fan not coming on in the summer? The temp of the van should stay around the middle of the gauge. Low speed fan should come on when the needle is a little to the right of the light. High speed should only come on at 3/4s hot and only after the low speed fan has been on for a while. If the low speed fan isn't coming on then you need a new fan resistor. I would also get the new thermostat and just get everything back on track.

Tony Sudney June 11, 2015

Hey Ken I was wondering about my problem of low engine heat in the winter. You stated that I may have received a couple of bad thermostats. My mind is forever going and a thought hit me; could it be that during the summer when engine heat gets very high;(I remember more than a couple of times in the Summer, in traffic the heat gauge went quite high and the hi-speed fan came on to cool the system), that the high heat ruined the thermostat to a point where it would not close, thus keeping the engine from coming up to running heat in the Winter.. This thought prompted me figure I would buy a new thermostat about the time the weather would start to become cool and then install it.. What do you think ?? Tony Sudney

Ken Wilford June 9, 2015

Just give me a call today or do it through the webstore. Here is a link to it in the store: 856-327-4936

Tony Sudney June 6, 2015

Hey Ken O.K., lets do the new thermostat bit, can do it with "VISA" Tnx for the info on it's location. I'll still have my boy do it !!! Tony Sudney 185 Lakeview Ave., Grosse Pointe Farms, MI 48236

Ken Wilford June 6, 2015

The thermostat is located over on the driver's side of the engine bay near the firewall that is toward the front of the van. You will see a black cap on it and you don't need to crawl under the van as the cap is actually pointing up for you to easily see from above. thermostat housing cover I would check the heater valve to see if it is opening all the way. You will have to drop the spare tire and look up from underneath. You will see it directly behind the radiator fan. Move the lever all the way to the red and then see if the arm of the valve is moving all the way over. I still suspect something isn't right with the current thermostat however since the van doesn't seem to be warming up all the way, the temp gauge and the heater not getting hot seem to confirm this. I can supply you with a new thermostat and you can have your son install it if you wish. It is pretty easy job done from above by removing four small bolts. Let me know if I can help further.

Tony Sudney June 5, 2015

Hey Ken Tnx for the response, wasn't expecting it. The thermostat was changed twice at a VW dealer service. I kind of knew the Mechanic, we got friendly because he also had a Vanagan, so, I guess I assumed he put in good thermostats. Oh, by the way, I live in the lower part of lower Michigan(read Detroit). Another fellow I met that was a VW mechanic told me to check the heater control under the spare tire. He said that the control cable has occasional tendencies to slip and the control may not be opening up all the way, Haven't done that yet. Where is the thermostat located?? I'm well over 80 years and can't crawl under cars like I used to, My number two son is my heavy, I have him do the crawling underneath... Tnx again!!! Tony Sudney

Ken Wilford June 4, 2015

Tony, the only way the air passing over the hoses should do anything is if you are living in Alaska or some where super cold like that. I am talking below zero temps. If you aren't then I am thinking it could be one of two things: You are getting crappy thermostats that just aren't allowing the engine to get warm enough or that maybe there is a problem with the front heater core itself. The thermostat: You can test the thermostat in a pan of water if you want to confirm if it is opening at the correct temp (87 degrees C or 188 F). Use one of the old ones that was replaced first to see if it is actually bad or not. The front core: Either it isn't flowing like it should so you aren't getting good heat or someone has done some work inside the heater box and thrown away the metal baffle plate that is in there, that prevents too much cool air blowing through the heater core. Either way you are going to have to rip apart your front heater box to see what is going on. If the baffle is in place then I would replace the core and that should fix the problem. Let me know if I can help you further.

Tony Sudney June 3, 2015

Sir My 1990 vanagan front heater gives very poor heat in the winter. The heat gage needle does not even come off the base line, had the thermostat replaced twice, but still cold. The rear heater works great, in fact it's the only heat I get in the winter. I've been told that the front heater is fed by two hoses underneath the van. While having the van in maitenance I was allowed to look under and saw those hoses. I think that those hoses being underneath in the slipstream near the roadway cools the coolent before it gets to the front heater. I will get a long piece of split foam tubing to slip over the hot feed hose isolating it front the cold air.. Tony Sudney

Leave a Reply

Want to join the discussion? Feel free to contribute!