[ramzsys]

Originally Posted by Catalyst_delhi

Do not remove the valve - Interestingly the system is designed to open the valve(no 12v input) when the engine is shut off to help cool down process , heat soak etc.

So this explains why the AC blows hot before blowing cold air when the air con is started!

[Catalyst_delhi]

Originally Posted by ramzsys

So this explains why the AC blows hot before blowing cold air when the air con is started!

This is normal behavior for this type of normally open heater control valves. The Heater control valve kind of helps dissipate heat after shutdown. Sad behavior though.At least it keeps the AC evaporator fungus free.

[RM2488]

Originally Posted by Catalyst_delhi

Do not remove the valve - Interestingly the system is designed to open the valve(no 12v input) when the engine is shut off to help cool down process , heat soak etc.

Not to discredit you or anything- I have messed with the diverter valve a lot over the last couple of months. My observations-
1. The valve, as you said, works in reverse- 12V for cold, 0V for hot.
2. Even when "closed", i.e. at 12V "cold", some coolant does go through the heater core, thus sacrificing A/C and blower efficacy. What it really does is open a "bypass". The original heater connection is still there- some water, probably via momentum flows through the core.

Hence, manually bypassing the valve gives me somewhat increased mileage, simply because it cools faster with the A/C, or sometimes I can do with only the blower (That is as cold as it gets in Mumbai- I have no use for the heater.)

What I fail to understand is, how the valve opening AFTER engine shutoff helps the cool-down process. The water-pump is turned off, and the blower is turned off as well- adding the heater to the circuit should hardly make a difference in this case.

My guess is that this is simply a defective fail-safe design from Ford- Under no condition will the coolant flow be impeded.

[Catalyst_delhi]

Originally Posted by RM2488

Not to discredit you or anything- I have messed with the diverter valve a lot over the last couple of months. My observations-
1. The valve, as you said, works in reverse- 12V for cold, 0V for hot.
2. Even when "closed", i.e. at 12V "cold", some coolant does go through the heater core, thus sacrificing A/C and blower efficacy. What it really does is open a "bypass". The original heater connection is still there- some water, probably via momentum flows through the core.

Hence, manually bypassing the valve gives me somewhat increased mileage, simply because it cools faster with the A/C, or sometimes I can do with only the blower (That is as cold as it gets in Mumbai- I have no use for the heater.)

What I fail to understand is, how the valve opening AFTER engine shutoff helps the cool-down process. The water-pump is turned off, and the blower is turned off as well- adding the heater to the circuit should hardly make a difference in this case.

My guess is that this is simply a defective fail-safe design from Ford- Under no condition will the coolant flow be impeded.

You are right, I was not 100% sure if that would help after shutdown but there is movement of water after the pump is shut off that is called thermo siphon. ( i know i am making a wild idea here) the water in the heater core will be cooler then the rest of the water. Hence when the engine is shut off this water should help. What you mentioned about fail-safe is also true. My heater valve gives cool air when i give 12v part # cc.

[RM2488]

Originally Posted by Catalyst_delhi

You are right, I was not 100% sure if that would help after shutdown but there is movement of water after the pump is shut off that is called thermo siphon. ( i know i am making a wild idea here) the water in the heater core will be cooler then the rest of the water. Hence when the engine is shut off this water should help.

The thermo siphon effect does not apply here- it is just a fancy name for convection, wherein hot water rises up, displacing cold water that will sink, and eventually the system will achieve equilibrium. However, since the diverter valve is ABOVE the heater core, the hot coolant will not sink into it. A bit of mixing will provide marginal cooling, definitely not enough for this system to be designed this way. And somehow, I tend to think that the company would actually want the engine to stay hot as long as possible after shutdown- less thermal stress, thus increasing reliability, and quick hot starts, increasing efficiency.

Originally Posted by Catalyst_delhi

My heater valve gives cool air when i give 12v part # cc.

Mine used to, before I diverted it. But it wasn't COLD, it was just a bit warm. Not as hot as the heater, not the middle setting. Around 5 degrees warmer than the outside air. I always wondered why. The intake is in the engine bay, but it couldn't account for this significant temp rise. Now that I have diverted the valve (again!), I find the blower temp to be only around a degree hotter than the outside. Goodbye A/C, hello mileage.

[Catalyst_delhi]

Originally Posted by RM2488

The thermo siphon effect does not apply here- it is just a fancy name for convection, wherein hot water rises up, displacing cold water that will sink, and eventually the system will achieve equilibrium. However, since the diverter valve is ABOVE the heater core, the hot coolant will not sink into it. A bit of mixing will provide marginal cooling, definitely not enough for this system to be designed this way. And somehow, I tend to think that the company would actually want the engine to stay hot as long as possible after shutdown- less thermal stress, thus increasing reliability, and quick hot starts, increasing efficiency.

Mine used to, before I diverted it. But it wasn't COLD, it was just a bit warm. Not as hot as the heater, not the middle setting. Around 5 degrees warmer than the outside air. I always wondered why. The intake is in the engine bay, but it couldn't account for this significant temp rise. Now that I have diverted the valve (again!), I find the blower temp to be only around a degree hotter than the outside. Goodbye A/C, hello mileage.

You are right! Did some research , even on 100% valve cycle , there was a bit a of coolant going to the heater core. Seems like I missed this. I diverted the cooling lines as well. Magic - My AC is even more freezing now. I am planning to use this diversion system - how long have you been diverting flow now? I hope nothing gets damaged. My engine is almost 124k km now and most possibly cannot survive overheating.

[RM2488]

Originally Posted by Catalyst_delhi

You are right! Did some research , even on 100% valve cycle , there was a bit a of coolant going to the heater core. Seems like I missed this. I diverted the cooling lines as well. Magic - My AC is even more freezing now. I am planning to use this diversion system - how long have you been diverting flow now?

Glad to be of help. I have no idea exactly how long it has been diverted, I only bought the car 6 months back, it was already diverted then. I put in a new valve for the monsoon (this being my first car), but the heater was horrible for defogging. The A/C was much better at it. Then I diverted it again because the warm blower air was driving me nuts. By the looks of it, I'd say it must have been diverted for three to four years now.

Originally Posted by Catalyst_delhi

I hope nothing gets damaged. My engine is almost 124k km now and most possibly cannot survive overheating.

No worries about overheating- four hours of idling in traffic, or a three hour highway drive- and my temp needle isn't even half way.

The reason you have a bit of a flow going even at 100% duty cycle is because of the way the valve is built- the heater circuit is never broken. The solenoid only opens a PARALLEL path for the water to flow. So MOST of the water uses the shorter path. But SOME of it goes through the core, merrily heating up my cold air.

[BinFord]

I had the same problem in my IKON TDCi and replace once under warranty. But it again failed and cooling was less.

When I asked Ford ASC they said it is a common issue with Ikon and only solution is to replace the Valve or disengage the heater. So I went for the latter one and removed the heater.

Result: Cooler air at all times .Sometimes difficult to afford and need to switch off AC .

[Catalyst_delhi]

Originally Posted by RM2488

Glad to be of help. I have no idea exactly how long it has been diverted, I only bought the car 6 months back, it was already diverted then. I put in a new valve for the monsoon (this being my first car), but the heater was horrible for defogging. The A/C was much better at it. Then I diverted it again because the warm blower air was driving me nuts. By the looks of it, I'd say it must have been diverted for three to four years now.


No worries about overheating- four hours of idling in traffic, or a three hour highway drive- and my temp needle isn't even half way.

The reason you have a bit of a flow going even at 100% duty cycle is because of the way the valve is built- the heater circuit is never broken. The solenoid only opens a PARALLEL path for the water to flow. So MOST of the water uses the shorter path. But SOME of it goes through the core, merrily heating up my cold air.

Thank you so much , Can you assist me by maybe posting a picture of your thermostat to diversion setup? I want to know which outlet of the thermostat is for which and which outlet is for the temp sender. I would be much obliged. Not a hurry though!

[sandeepmohan]

A problem I found highly annoying in my previous car, a Ford Ikon. I was scared to even touch the temperature control. You have no choice. Who wants to freeze in the car. In the two years I owned this car, I must have replaced the valve three times. If we had laws that worked, I would have sued Ford India for just sitting on this design and not improving it even after 10 years. This part does not come cheap too. It is still expensive.

[RM2488]

Originally Posted by Catalyst_delhi

Thank you so much , Can you assist me by maybe posting a picture of your thermostat to diversion setup? I want to know which outlet of the thermostat is for which and which outlet is for the temp sender. I would be much obliged. Not a hurry though!

I'm not sure I get you- I did absolutely nothing to the thermostat. I just bypassed the heater- the way the diverter valve should, in theory.

BTW, if you do mean the actual hoses by "temp sender" then it is quite simple- the side with the solenoid is the "hot" side.

I had an idea for a proper replacement with manually controlled valves. This way I would always have the option of turning the heater on, at least manually. But then I figured it's probably not worth the expense, since I hardly ever end up using it. Strangely enough, the cost worked out to be cheaper than the replacement valve at Ford ASC.

[Catalyst_delhi]

Originally Posted by RM2488

I'm not sure I get you- I did absolutely nothing to the thermostat. I just bypassed the heater- the way the diverter valve should, in theory.

BTW, if you do mean the actual hoses by "temp sender" then it is quite simple- the side with the solenoid is the "hot" side.

I had an idea for a proper replacement with manually controlled valves. This way I would always have the option of turning the heater on, at least manually. But then I figured it's probably not worth the expense, since I hardly ever end up using it. Strangely enough, the cost worked out to be cheaper than the replacement valve at Ford ASC.

I thought of using another cars manual control as well . Something lever controlled. I actually wanted which outlet of of the thermostat housing goes to which part of the heater valve. Thanks a lot for your time

[RM2488]

An update: I got the air conditioning system completely serviced- cleaned evaporator, compressor oil top up, gas charging, etc. While I was at it, I got rid of the heater core. It was useless for me anyway, with no heater. What it means is I get better air flow with the blower and A/C. The blower is now whisper-quiet at setting two, and barely audible at three. Win-Win.
P.S. I never knew the Ikon A/C was this powerful! It's really chilling! Now, what do I do with a heater core...
P.S. 2- With the heater now completely eliminated, it leaves me free to mod the A/C controller so it takes up only 1 DIN instead of two... makes room for a 2-DIN touchscreen. Work in progress.
P.S. 3- I also managed to pull a FE of 12 KMPL with full A/C on a hot afternoon long drive. My previous FE was close to 10.

[Catalyst_delhi]

Originally Posted by RM2488

An update: I got the air conditioning system completely serviced- cleaned evaporator, compressor oil top up, gas charging, etc. While I was at it, I got rid of the heater core. It was useless for me anyway, with no heater. What it means is I get better air flow with the blower and A/C. The blower is now whisper-quiet at setting two, and barely audible at three. Win-Win.
P.S. I never knew the Ikon A/C was this powerful! It's really chilling! Now, what do I do with a heater core...
P.S. 2- With the heater now completely eliminated, it leaves me free to mod the A/C controller so it takes up only 1 DIN instead of two... makes room for a 2-DIN touchscreen. Work in progress.
P.S. 3- I also managed to pull a FE of 12 KMPL with full A/C on a hot afternoon long drive. My previous FE was close to 10.

How are you going to achieve point 2 , I am interested in this. I have not removed the heater core but have looped the hoses going into the heater matrix. I intend to use a manual control valve for the heater from some other car.(more like a tap rather than dodgy solenoids)

[RM2488]

I have come up with several options-
A. Since the temperature control is now defunct, I can shift the air circulation flap switch and A/C switch in it's place and cut off the top half, making it 1-DIN.

B. Get a 1-DIN panel from a different car and mod it to fit.

C. Build my own panel.

Since I have all the schematics for the panel, it isn't difficult to replicate its workings. B and C are similar. If I take option C, I'm thinking either laser-cut acrylic or molded polyester resin cast would be aesthetically pleasing.