Hello all, ive been looking at the threads on horizontal rads ,correct me if i am wrong but i have a hybrid
my townace is a 89 super extra td with 2wd and auto yet it has a horizontal rad and fans , however there are no thermo sensors on the filler neck - is this horizontal rad an extension of the vertical rad and how does it connect to the pipe work of the main rad because i can see no diverter pipes from the main rad tothis horizontal rad - or does it connect into the pipework at another point - dave

- (#5382) dave stait, 3 Sep 02

That's your aircon condenser...

- (#5383) david miller, 3 Sep 02

I've never made sense of all the postings about radiators. Is this collation anything like right?

Apart from the main, vertical, radiator...

2WD/RWD have a smaller, vertical a/c condenser in front of it and a horizontal a/c condenser with two single-speed electric fans. (The two a/c condensers get hot and are air-cooled like the water radiators.)

4WD (auto & manual?) have a secondary medium sized water radiator and just one a/c condenser, both located horizontally with two 2-speed electric fans above the whole lot. If you turn on the a/c, they will run slowly. There is a thermal switch at about 105C in the coolant filler to make the fans come on at full speed.

To add to the confusion all versions cool the cabin air with two a/c evaporators (which get cold) on which humidity from the air condenses and drains from tubes, one offset to the left, quite near the front, the other around the middle of the vehicle.

Automatics have the transmission oil cooled by (part of? how?) the main vertical radiator. There are no other oil coolers?
- (#5384) Dave Mason, 4 Sep 02

The horizontal rad belongs to 4x4 Autos ony AFAIK.
You're right about the condensers though, Dave. I think the horizontal one is only if you have a coolbox.
Plus 4x4 autos have an additional little condenser behind the bumper. Looks just like an oil cooler.
The autobox is cooled by a coil in the L/H (cool) rad tank, the engine oil cooler is what the oil filter screws onto- the pipe snakinh round the rear of the block is it's return.
Useful to note at this point perhaps that the r/h pipes are all hot, the l/h are all returns.

- (#5385) david miller, 4 Sep 02

Dave, David,
We don't have cool box (Thank goodness) but still have the main air con condenser which is horizontal (with the two electric fans) and the little secondary condenser about 3 inches high mounted vertically in front of main condenser. As David rightly says, engine oil cooler is a pipework affair running around top of engine, auto gearbox oil cooler is a coil inside the main vertical rad, and then the 4x4 models have the extra horizontal radiator that the RWD models don't seem to get. My only assumption about the 4x4 models getting the 'extra' cooling is that they expect you to use 4 wheel drive & low ratio, hence you wouldn't have the ram air cooling due to high revs & low speed, (maybe I'm missing something completely here though). What a plumber's nightmare these vehicles are really. Regards Rob.

- (#5386) Rob Drinkwater, 4 Sep 02

Sorry as an amendment to last post, it appears that Dave is correct, there are two small air con condensers on 2WD models, one infront of vertical rad & one on it's own, horizontal infront of this, with only one electric fan on the horizontal condenser. The 4WD models only have the main larger condenser (which is in fact two smaller ones linked via a U shaped pipe) above the horizontal rad, with two electric fans on it, and then this little extra condenser vertical infront of that setup. Hope this clarifies this. Rob.

- (#5387) Rob Drinkwater, 4 Sep 02

Great. I was particularly wondering about that little condenser behind the bumper, I wondered if it WAS an oil cooler, which is why I asked about those.

So we all have 2 a/c condensers, I presume that's one for each system, though on 4x4 one of them is very small. Is there an extra one for a coolbox?

Anyone comment on whether the rare 4x4 Manual (there were a few in my survey in February) definitely has the extra water radiator or not. David thinks not but Rob's assumption suggests that it does.

I'll see what else gets posted and then try again to write "a new owner's guide to Townace radiator-like thingies" so Ace Answers is less muddled, on some points at least.
- (#5388) Dave Mason, 4 Sep 02

According to the cd, the horizontal rad is CR30 auto only. The condensers appear to be in parallel with each other- remember that the compressor, receiver/dryer etc are common to front, rear, and coolbox. The little condenser at the front is different. It doesn't appear to exsist on petrol models in the UK and US, only being specified (again) in the CR30 auto.
It looks like some basic Japanese models only have the upright condenser.

- (#5389) david miller, 4 Sep 02

David is right CR30 auto has horizontal rad, CR30 manual doesn't, don't know why, maybe it's just Toyota thinking auto, off road, in crawler gear needs extra cooling. The three condensers on the CR30 are connected in series to cool the refrigerant back to it's liquid state. Still can't quite see the point of the little tiny one in the front of the chassis. I suspect that there will be different refrigerant capacities on all the models as the different configurations can't all require the same weight of refrigerant. I think I'll experiment with mine to get the best out of the A/C system. I'll let you know wht works out to be the best amount. Regards Rob.

- (#5390) Rob Drinkwater, 4 Sep 02

So, if the 'extra' water rad is for Auto rather than for 4WD this may be because the main rad has the transmission oil to cool as well.

One more
there is a heat exchanger visible behind the grille just above the battery. That's the rear heater matrix? Where's the rear a/c evaporator? in the roof? or is there an air duct going up beside/behind the driver?

And the two condensers, as it's all one system it would make more sense if they were in series - the small one "finishes off" the cooling? Not a problem either way.

- (#5391) Dave Mason, 4 Sep 02

the rear a/c evaporator is behind the intake grille for the heater. That fluff- covered thingie...
The cold air is ducted up to the roof vents.
The heater matrix is lower down, under the fan unit.

- (#5392) david miller, 4 Sep 02

I understand that the rear heater matrix is always hot. So are there two completely separate cabin air routes for the rear system, heating and a/c? Where is the inlet for the rear heater? What happens if you put the rear airflow (not temperature) control in the middle? if that's not deviating too far off subject!

- (#5423) Dave Mason, 6 Sep 02

Dave, both front & rear heater matrices are always hot (except when engine is cold obviously) unless you have a valve on the engine (like the old minis) to shut the flow through the matrix, hot coolant will always flow through them. The thing that controls the amount of heat intriduced into the car is which way the flaps go, if the flow is pushed through the matrix, it will heat the air & you have heat, if it is pushed past the matrix you have cold, a mixture & you have warm air, you get the picture. On the Townie series the rear system is recirculate only, the intake to the fan is on the mid bulkhead behind the driver, behind a grille, basically it takes air from there & uses the fan to circulate it to the place you have selected on the panel, top or bottom, however the air con evaporator is in the way of the flow to the top vents, so only cold can come from there (Toyota working on the cold air falls principle) and the heater matrix is in the way of the bottom vent flow, hence heat from the bottom (Again on the principle of warm air rises) therefore if you want maximum cooling from the rear A/C then the top vents must be used, maximum heat, bottom vents. If you put the distribution control in the middle, then you will get Air conditioned air from the top vents (assuming A/C control is on) and non air conditioned air, at the temperature you have set on the heater control from the bottom vents. I also assume that the reason the rear Air Con has a rotary control, rather than an on-off switch, is that it has a variable control valve on the rear evaporator, this means that you can in effect vary how cold the rear air con gets with this control. Hope this clarifies the rear system. Front is much more conventional, heater control varies temperature that the air comes out, distribution control blows the air where you put it, A/C switch adds in the cooling effect, and the fan switch varies how fast the air flow is, also the recirculate control determines if you get fresh air in from outside, or if it recirculates the air from within the vehicle. HTH Rob.

- (#5445) Rob Drinkwater, 6 Sep 02

Excuse me pursuing this but I think it will be useful for Ace Answers...
The rotary control on the rear climate control system is for blower speed
Off/Auto/L/M/H (see Ace Answers, Bodywork, John Corfield, Rear a/c controls access), so maybe not controlling the refrigerant flow, Rob. A slight difference from the bottom slider on the panel for the front system is that pushing that rear knob down toggles the rear system on/off, as can be done with the driver's rocker switch, its state being indicated by the amber lights at both switches.

Back to heat exchangers - surely the rear aircon evaporator is in the way of the airflow to both top and bottom outlet vents - isn't it the first thing inside the inlet grille?

- (#5446) Dave Mason, 6 Sep 02

If I may take you up on one point, Rob. The front heater circuit IS fitted with a water valve. It's under the floor at the front.
And yes, Dave, the evaporator does come first. But that's OK because the heater will always reheat the air (which has been dried by the a/c...)

- (#5447) david miller, 6 Sep 02