Friday, January 9, 2009

Winter Heat Requirements

Our winters in Canada can be quite cold with icy conditions like ice pellets and freezing rain. Not having any experience driving an EV in such conditions, I wasn't sure if a single 1500 watt electric/ceramic heater would be enough to keep the windshield clear and the car interior warm enough. I decided to ask Richard Lane who gracefully continues to answer my occasional questions. From reading his answers to my emails, I now realize that one heater might suffice for keeping the car warm but might not be enough for bad weather like freezing rain. Richard has done many conversions over a period of approximately 15 years in Ottawa so if anyone knows it is certainly him.

The space in the heater unit of the Mazda Protege does not permit me to fit two ceramic heaters so my next option is to use the space occupied by the A/C evaporator inside the cooler unit. I dismantled the cooler unit and removed the evaporator. Inside, there was some debris (pieces of leaves) and dirt (mostly dust) as this is the first unit in the air path after the fan/blower so I vacuumed and wiped the inside of the cooler unit clean and will prepare it for an additional heater. I am also wondering if it would be wise to place a screen inside the cooler unit on the fan side to prevent debris like leaves from coming in direct contact with the heater.

Here is a shot of the cooler unit (right), A/C evaporator (left) and electric heater (center). I will have to obtain a second heater and adapt it to fit in the place of the original A/C evaporator.

In the meantime, I built a support for the heater that will be housed in the heater unit. I visited the local metal recycling/scrap yard again and picked up a nice piece of aluminum sheet and angles for a bargain $4. I also cut out some spacers made of 3/4" plywood.

I then folded up the upright front and back parts of the support followed by the slightly curved shallow folds on the sides. With a pencil, I marked the outline of the electric heater mount.

Here is the electric heater placed in the center of the support in order to determine the cutout area that will permit air to flow through the new heater.

The first electric heater that I purchased is a DBK HR01-C, 10/22, 100...120V (1500 W). It will be placed in the heater unit replacing the original heater core:

The second electric heater will be placed in the cooler unit replacing the original A/C evaporator (no cooling) and will likely be purchased from Canadian Tire (brand and spec not yet known).


1 comment:

MindMil said...

I am thinking of two 1500W heater cores for my Honda HR-V as well. It is usually 0..-5C and sometimes gets to -20C (recorded extreme -33C) in Lithuania so it's no fun driving in the cold. I am also thinking about pre-heat feature which is would be remote controlled. It would be similar to what I have installed in my petrol Subaru. It is nice to come to warm car in the morning. No ice scraping is a plus :)