Zerostart circulating heater install MK5 Jetta TDI

Last couple of winters has been kind of hard on the old Jetta TDI in the mornings when it is near zero outside. As the TDI’s age, they have a harder time starting in the freezing temperatures, so adding an inline coolant heater is a great way to warm the car up before starting. Up north, block heaters and circulating tank heaters are a common item found on cars, but down in Kansas, we don’t see them as much. Been a long time since I have had an electrical cord sticking out the grill of the car 🙂 This should also give nearly instant hot heat out the vents since the coolant will already be warm.

I used the zerostart 1000w circulating heater for this job. A company called Frostheater sells these kits with the hoses for your specific application, but they are months out on delivery, so I picked up the same heater they use and made my own kit. I also mounted in a different location which I feel is far better than where they mount by the fans. No special hoses needed, just hook up and go. It also then allows you to pop the electrical plug out the driver side fog light grill since the cooler is right there.

I chose to mount the heater on the driver side frame rail between the transmission and the radiator. There are 2 studs sticking down off the frame, so I used a simple wide L bracket attached to the heater, and then bolted right on the frame. This allows you to run a straight piece of 5/8″ heater hose directly to the front port of the exchanger, and up to the cooler on top of the transmission.

Coming off the top of the heater, I brought the hose up through the opening in the fender, and across the transmission making a loop to the cooler. It slides right under the intercooler ducting and attaches to the cooler.

To here.

I believe this is where the frostheater kit hangs from in this opening between the fans and the engine, but with the bulky heater, there isn’t much clearance, and then you trying to find a hose with the right angle and bend in it, and I just wasn’t that interested in messing with that. Here you can also just barely see the lower connection that runs straight across from the heater. It is hard to see, but there are 2 hose connections on the silver looking box, we use the front most connection (this runs up to the cooler on the trans normally). I just disconnected the stock hose at both ends, and left it in place in case I ever want to take the heater out. A heavy duty indoor timer will be set to come on at about 3am, which will allow the heater to heat up the car for a couple hours before leaving the house by 6.