A lesson in AC for idiots like me...
08-23-07, 02:10 PM
#29
one relay is activated by the coolant thermoswitch, and triggers low speed. The switch turns on at 207 and off at 195.
One relay is activated by the a/c relay (compressor) and triggers high speed.
The fan isn't made to have both sides energized at once, and I originally intended to run a different relay configuration that would run EITHER the coolant switch OR the a/c activation at low speed, but when BOTH were active (a/c on and coolant temp over 207) the fan would turn on high. However, I couldn't get it to work, the thermoswitch seemed unable to trigger 2 relays, which is what was necessary to make it operate this way.
After thinking about it more, it seemed the since the high speed moves so much air, it stands to reason to me that it's unlikely the coolant will ever reach the thermoswitch's turn on temp, and so there is little risk of having both circuits on at the same time for very long at all.
One relay is activated by the a/c relay (compressor) and triggers high speed.
The fan isn't made to have both sides energized at once, and I originally intended to run a different relay configuration that would run EITHER the coolant switch OR the a/c activation at low speed, but when BOTH were active (a/c on and coolant temp over 207) the fan would turn on high. However, I couldn't get it to work, the thermoswitch seemed unable to trigger 2 relays, which is what was necessary to make it operate this way.
After thinking about it more, it seemed the since the high speed moves so much air, it stands to reason to me that it's unlikely the coolant will ever reach the thermoswitch's turn on temp, and so there is little risk of having both circuits on at the same time for very long at all.
08-23-07, 03:27 PM
#30
one relay is activated by the coolant thermoswitch, and triggers low speed. The switch turns on at 207 and off at 195.
One relay is activated by the a/c relay (compressor) and triggers high speed.
The fan isn't made to have both sides energized at once, and I originally intended to run a different relay configuration that would run EITHER the coolant switch OR the a/c activation at low speed, but when BOTH were active (a/c on and coolant temp over 207) the fan would turn on high. However, I couldn't get it to work, the thermoswitch seemed unable to trigger 2 relays, which is what was necessary to make it operate this way.
After thinking about it more, it seemed the since the high speed moves so much air, it stands to reason to me that it's unlikely the coolant will ever reach the thermoswitch's turn on temp, and so there is little risk of having both circuits on at the same time for very long at all.
One relay is activated by the a/c relay (compressor) and triggers high speed.
The fan isn't made to have both sides energized at once, and I originally intended to run a different relay configuration that would run EITHER the coolant switch OR the a/c activation at low speed, but when BOTH were active (a/c on and coolant temp over 207) the fan would turn on high. However, I couldn't get it to work, the thermoswitch seemed unable to trigger 2 relays, which is what was necessary to make it operate this way.
After thinking about it more, it seemed the since the high speed moves so much air, it stands to reason to me that it's unlikely the coolant will ever reach the thermoswitch's turn on temp, and so there is little risk of having both circuits on at the same time for very long at all.
08-23-07, 07:04 PM
#32
Rotary Freak
Join Date: Dec 2006
Location: New Hampshire
Posts: 1,791
Likes: 0
Received 0 Likes
on
0 Posts
I wish I had A/C. I will be buying the parts to put it back in. Why I removed it 6 years ago is beyond me. Maybe because it never worked. Just like how I was to lazy to put a belt on my PS pump and was not to lazy to spend the time in removing the PS system 
08-24-07, 06:20 AM
#35
).
08-24-07, 08:11 AM
#36
ERTW
iTrader: (1)
Join Date: Oct 2002
Location: Ottawa, Canada
Posts: 4,328
Likes: 0
Received 0 Likes
on
0 Posts
does the stock little electric pusher fan come on anytime the A/C is on?
i thought it did, and also if coolant temp gets above a certain point...
and my S5 NA came with one so it's not just the turbo models that got them.
i thought it did, and also if coolant temp gets above a certain point...
and my S5 NA came with one so it's not just the turbo models that got them.
08-24-07, 12:12 PM
#37
Lovin my 7
I have a compressor if you want it
08-24-07, 02:51 PM
#39
ERTW
iTrader: (1)
Join Date: Oct 2002
Location: Ottawa, Canada
Posts: 4,328
Likes: 0
Received 0 Likes
on
0 Posts
interesting that my car came with one. i am fairly certain that the car was never an automatic, and the fan looks old enough to have been on since 1989.
are you sure it wasn't an S5 specific thing for cars with A/C? or possibly for Canadian models, which doesn't make much sense though...
are you sure it wasn't an S5 specific thing for cars with A/C? or possibly for Canadian models, which doesn't make much sense though...
08-25-07, 02:16 PM
#40
1 BAD 7
Join Date: Feb 2003
Location: Miami,Fla
Posts: 277
Likes: 0
Received 0 Likes
on
0 Posts
I found this same lesson out a few months back when I was just getting my FC running after the build. I had charged it full of freze 12 but it wasn't cooling at idle. I was in the engine bay fooling around while the engine was idling with the a/c on, to see if I could see any issues. After several minutes I hear a loud noise and see freon being blown out in the engine bay, so I kill the a/c.
Get to looking around and see that there is dye/freon near the compressor on the firewall, and near the radiator at the dryer.
Come to find out the stock clutch fan wasn't moving enough air at idle to keep the pressure down (or the system cool). When pressure got too high, the "pop off valves" on the compressor and dryer opened and vented the pressure (and freon with it). Apparently these are setup to prevent compressor and dryer explosions like you had.
I had to recharge the whole thing, and after I went with the escort e-fan, not only have the pop off valves never opened again, but the system is a WORLD colder at idle than it was previously. Now, instead of being like 'what the ****, why isn't the air working" while in traffic, I am like "wow, this is actually sufficient". Granted, it never gets cold enough to make me want to turn it down from high while in traffic, but for an rx7 a/c it is truly kick ***.
Going down the road the thing gets really cold though, still not as cold as some other cars, but certainly enough that you want to turn it down to 1/2 or 2/3.
I have my fan set up to come on with the coolant thermoswitch on low speed, and the a/c relay activation on high speed. This seems to work very well so far.
Get to looking around and see that there is dye/freon near the compressor on the firewall, and near the radiator at the dryer.
Come to find out the stock clutch fan wasn't moving enough air at idle to keep the pressure down (or the system cool). When pressure got too high, the "pop off valves" on the compressor and dryer opened and vented the pressure (and freon with it). Apparently these are setup to prevent compressor and dryer explosions like you had.
I had to recharge the whole thing, and after I went with the escort e-fan, not only have the pop off valves never opened again, but the system is a WORLD colder at idle than it was previously. Now, instead of being like 'what the ****, why isn't the air working" while in traffic, I am like "wow, this is actually sufficient". Granted, it never gets cold enough to make me want to turn it down from high while in traffic, but for an rx7 a/c it is truly kick ***.
Going down the road the thing gets really cold though, still not as cold as some other cars, but certainly enough that you want to turn it down to 1/2 or 2/3.
I have my fan set up to come on with the coolant thermoswitch on low speed, and the a/c relay activation on high speed. This seems to work very well so far.
Kevin so what you’re basically saying is that with the Escort E-Fan your AC is blowing a hell of a lot colder than running the stock fan with shroud?
I’m curious to know are you running a FMIC with your setup, if so what are your water temps while cruising or at idle for example in traffic?
I have always wanted to run a E-Fan preferably the "Black Magic E-Fan 150", but I think Jrat said he had two of them that went bad on him within a short time period. The only reason that really want to run an E-Fan is to remove the clutch fan so the water pump doesn’t work as hard, and also it's one less belt that you have to worry about, not to mention that it frees up a lot of space so you can work better in the engine bay, and it also looks better than the stock fan and shroud, and also you don’t have to worry about the clutch fan going bad either. I know my reasons are minor if not insignificant to me wanting to run an E-Fan on my Turbo-II. I have asked and spoken to a lot of veterans and they all tell me one thing "Nothing works better than the stock fan and shroud!" If that’s the case then why did Mazda go with E-Fans on the FD's when they first came out? Maybe it was due to a lot of R&D from Mazda before they went to E-Fans from the Stock clutch fan and shroud? All I can say is E-Fans do work if they are properly installed if they didn’t then all the newer cars would not be using them at all. I think the E-Fans are much more efficient and reliable than a clutch fan; then again this is my opinion. I want to run an E-Fan, but I am paranoid that with the AC and a FMIC that my car will run hot compared to running the stock fan and shroud. I will be upgrading to a Koyo, Fluidyne, or a Ron Davis radiator in the near future.
As far as cooling is concerned my car runs normal, I’m just worried that with the FMIC in place the radiator wont be getting adequate airflow which will cause me to overheat.
08-25-07, 02:45 PM
#41
I think I might take Kevins idea a bit here. Might rig up a nice little 8 inch fan and mount it on the Condenser and make it come on when the AC is turned on..
08-25-07, 02:50 PM
#42
In contrast that escort fan on high will move a shitload of air. Some guys claim as much as 2800cfm...it's the same fan as the taurus and some other fords, and plenty of mustang and hotrod guys use them on other applications too. When the ****** kicks on while the hood is up, it will blow a shop rag laying on the alternator about 3 foot out of the engine bay.
08-25-07, 02:52 PM
#43
Keep to the right.
iTrader: (10)
Join Date: Jul 2001
Location: Mascoutah, IL
Posts: 793
Likes: 0
Received 0 Likes
on
0 Posts
My '86 Base is set up with an extra relay and fan to come on with the A/C as you guys have been talking about and it works really well. This was done by the previous owner of my car who was a Mazda Master Tech.
08-25-07, 02:58 PM
#44
I’m curious to know are you running a FMIC with your setup,
if so what are your water temps while cruising or at idle for example in traffic?
No, I have not seen fit to gay up my interior with a bunch of gauges hanging everywhere, so I've been making due with the wideband and boost gauge in the instrument cluster surround. The power FC commander will display coolant temp (and air intake temp, and other stuff) so I am anxious to get it in. My fan thermoswitch is activated at 207, and it runs about half the time while driving and 2/3 of the time while idling, which I'd consider normal.
I have always wanted to run a E-Fan preferably the "Black Magic E-Fan 150", but I think Jrat said he had two of them that went bad on him within a short time period. The only reason that really want to run an E-Fan is to remove the clutch fan so the water pump doesn’t work as hard, and also it's one less belt that you have to worry about, not to mention that it frees up a lot of space so you can work better in the engine bay, and it also looks better than the stock fan and shroud, and also you don’t have to worry about the clutch fan going bad either. I know my reasons are minor if not insignificant to me wanting to run an E-Fan on my Turbo-II. I have asked and spoken to a lot of veterans and they all tell me one thing "Nothing works better than the stock fan and shroud!" If that’s the case then why did Mazda go with E-Fans on the FD's when they first came out? Maybe it was due to a lot of R&D from Mazda before they went to E-Fans from the Stock clutch fan and shroud? All I can say is E-Fans do work if they are properly installed if they didn’t then all the newer cars would not be using them at all. I think the E-Fans are much more efficient and reliable than a clutch fan; then again this is my opinion. I want to run an E-Fan, but I am paranoid that with the AC and a FMIC that my car will run hot compared to running the stock fan and shroud. I will be upgrading to a Koyo, Fluidyne, or a Ron Davis radiator in the near future.
As far as cooling is concerned my car runs normal, I’m just worried that with the FMIC in place the radiator wont be getting adequate airflow which will cause me to overheat.
As far as cooling is concerned my car runs normal, I’m just worried that with the FMIC in place the radiator wont be getting adequate airflow which will cause me to overheat.
The FD's have e-fans because the radiator is farther forward and also angled down at about 60* from the engine, making a shroud difficult to set up, Same for the rx-8s whch are set up almost the same way. Plus they use dual e-fans which allow for several stages/speeds for cooling under different conditions based on coolant temp and a/c activation.
09-06-07, 07:49 PM
#45
Just take the blue pill..
I came across a stock electric fan and I am looking to add it to my A/C setup using a relay that allows it to come on with the A/C compressor. Does anybody have a little quick reference wiring diagram for hooking up a relay to do this with the stock electric pusher fan? Also, if I can't get r12 or freeze12 then am i going to have to get that kit posted on the first page to run r134?
Thread
Thread Starter
Forum
Replies
Last Post
MILOS7
3rd Generation Specific (1993-2002)
0
09-18-15 03:39 PM