The (Canadian made) engine block heater for the TCH is a 400-W unit. That means that it consumes 1 kWh of electrical power every 2.5 hours of use. In this time period it will get fairly close to the equilibrium block temperature. What happens is that the block temperature will rise above the ambient temperature until the rate of heat loss from the block is equal to the rate of heat input from the heater (400 W equivalent). So, the heater ultimately (i.e., after a long time) raises the block temperature to a specific amount above the ambient temperature, no matter what that ambient temperature happens to be, summer or winter. My measurements with my TCH show that the ultimate temperature rise is 25-30 degrees C (45-54 degrees F), and that one gets reasonably close to this ultimate rise after about 3 hours. I use my block heater both summer and winter. My calculations indicate a net cost savings, and I get a much quicker warmup especially in the winter.

Stan

 

Now, that's what I was looking for.

Stan knows his TCH and his auto mechanics and his economics. And - (What can I say ?) - he's Canadian; so, he must know block heaters!

Seems to me like they ought to be standard equipment and used all year everywhere.

And, in addition to the fuel savings, I would suppose that warmer, easier starts every day would mean significantly less engine wear and probably longer motor/generator and battery life as well.

 

The cost of 1 kw of electricity for one hour is about nickle or so. The block heater is around 500 watts. That's only 2 1/2 cents per hour. A few pennies vs the 3 to 5 mpg when you drive off from home on a cold winter morning. Even after a half mile my car would only be up to about 10/12 mpg. This was before I decided to install the block heater.

It's hard to figure due the few miles it takes for the engine to heat up normally during a cold winter morning. Compare it to today's high cost of gas. I think the heater would be the best way to go.

I was told by a toyota North Dakota shop foreman last summer, that the newer block heaters only work when the outside temperature is below zero. The reason being that toyota found the engine was not starting early enough to warm the catalytic converter.

I can't find any information anywhere to back this his statement. Perhaps toyota dropped the idea. Think about it, a device that waits for 0 degrees then it kicks on at 400 or so watts of heat. How would it know to stay heating.

 

And then , by my observation, that is followed by another couple of miles over which the penalty is the difference between an average of 12-20 mpg vs the fully warmed up city result of 30 mpg or so.


Jimmy,

This is highly interesting and important info. and is your heater one of the new ones or one of the old ones? Can you give us your part number?



Stan,

Please comment on this.

Is your experience with the"old" one, or does this change even apply in Canada?

And can you give us your part number as well?

Thanks

Jack

 

Smilin' Jack — I'll have to check at home to find my block heater part number. I'll let you know. It was installed in Spring 2007 as I recall, after I'd experienced how long it took my TCH to warm up during its first winter (2006/07) — in fact, due to my short commute distance (~1 mile each way), it never even reached full operating temperature. I decided that ICE wear and fuel consumption would both be reduced by using a block heater each morning. I have used it ever since. It's certainly an "old" one.

rburt07 — I'm suspicious about the statement that there's a thermostat in the new block heaters, but I can't say yea or nay from my own experience. I suspect that the Toyota parts man doesn't understand that a thermostat is not needed to prevent the block temperature from rising towards infinity! What happens physically is that the heater generates heat energy at a certain rate, proportional to the heater's wattage rating. This heats up the water and engine block. As the block's temperature rises above the ambient temperature of its surroundings, it starts to lose heat to its surroundings. The higher the block's temperature becomes, the more rapidly it loses heat energy to the surroundings. At some temperature differential between the block and its surroundings, the rate of heat loss by the block will equal the rate of heat generation by the block heater. At this point, the block's temperature stops rising. This mechanism is self-limiting. No thermostat is needed. My measurements show that the ultimate temperature differential with my 400-W block heater is 25-30 degrees C. My bet is that there's actually no thermostat in the new block heaters, and they may be identical to the old ones.

The catalytic converter operates at such a high internal temperature that the change in ambient air temperature between summer and winter is really only a relatively small change compared with this. So, I don't believe the catalytic converter has anything to do with the block heater. In summer, the car's engine control system goes from open-loop to closed-loop operation within about 1 second of ICE starting. In the dead of winter I found that it could take 30-45 seconds or so to switch to closed-loop operation when starting with a very cold ICE. I don't recall checking the time taken to go to closed-loop in very cold weather when starting up with a block-heater-pre-warmed ICE. I'll try to remember to check this out next winter.

Stan

 

Stan,

Thanks in advance for the part number if you get it.

I'm about to follow your lead (re. installing a heater and using it summer and winter), and if they have limited the performance of the heater offered in the US, I may look into obtaining the Canadian made one.

I suspect that you are right about the unlikelihood of a thermostat addition, but who knows? They've done stranger things, or perhaps the presently offered US version may be less powerful.

Jack

 

OK, I've been following this thread for a while and you guys talked me into it. I had the dealer install a block heater ($85CAD parts + $41 labour) during a scheduled oil change this past week. I've seen my FE take a good hit these last two winters and since my commute is only 15km a good percentage of my winter driving is during warm up.

Question though, anyone with good ideas how best to run the cord? The dealer secured it such that the plug has about 6" of slack to get at it after popping up the hood, but I'd like to figure out an easier way to plug/unplug without leaving a cord dangling.

PS the part number they listed on the invoice for the block heater was PU140-00900.

 

I run mine through the lower grill. I wrap it around one of the slats and tie it off so it won't fall to the ground. When It's not plugged it, I just stuff it inside with only the plug itself sticking out. I leave about 6" of slack so it's easy to pull out again and plug it into an extension cord.

 

I found this post from Yahoo marked, January 2008, to be very interesting.

http://autos.groups.yahoo.com/group/...id/message/502

 

I found the old message where I mentioned about the temperature with the newer engine block heater.

I was the shop foreman that tole me the newer toyota block heaters won't work unless the outside temperature is
0 degrees or colder. Looks like they may have abandoned this. I read in other forms were various toyota block heaters gets hot even above zero degrees.

I can't find where some online toyota parts list the various block heaters for he prius and camry. Back in '07 when I bought mine they were two separate units and part numbers. I think this new number may fit both hybrids.