AC Problems
My 99 F350 V10 is having AC problems. It will blow cold for 10 minutes than it blows hot. Any ideas ??? 
AC Problems
Senior User
Joined: Jun 2005
Posts: 116
Likes: 0
From: Bridgewater, NJ
Most likely it's low on refridgerant, and when the pressure of the system rises quickly the high pressure switch cuts the compressor out. If the system is in fact fully charged, a faulty pressure switch could be the culprit. Another possibility is that the evaporator coil inside the cab of the vehicle is clogged with dust, and isn't allowing for full air flow across it and is icing up.
Posting Guru
Joined: Apr 2004
Posts: 1,342
Likes: 0
From: Georgia
Look to see if the compressor clutch is engaged or not when the a/c turns hot. If it is still engaged it is probably the heater/AC bypass door letting hot air by. If it is not engaged it is probably low on freon or a bad low pressure switch. (The switch will shut the compressor off if low on freon so if it is bad it is tricking the system into thinking it is low.)
Posting Guru
Joined: Apr 2004
Posts: 1,342
Likes: 0
From: Georgia
Fredvon4
I looked at the site. I have often wondered why my truck did not have a heater control valve. All my other vehicles have all had one. It looks simple enough to install. What does the small hose go to that comes with the kit? Is it vacuum operated or manual? Seems like you could just go and buy a generic heater control valve.
I looked at the site. I have often wondered why my truck did not have a heater control valve. All my other vehicles have all had one. It looks simple enough to install. What does the small hose go to that comes with the kit? Is it vacuum operated or manual? Seems like you could just go and buy a generic heater control valve.
Logistics Pro
Joined: Jan 2002
Posts: 3,733
Likes: 38
high ho silver
The little hose is vacuume control so the "by pass" is only closed in the Max AC position but you can tie the line into any one of the modes. and yes a manual valve will work, but caution!.... completely closing all flow to the heater core can cause the core to corrode and leak.
The little hose is vacuume control so the "by pass" is only closed in the Max AC position but you can tie the line into any one of the modes. and yes a manual valve will work, but caution!.... completely closing all flow to the heater core can cause the core to corrode and leak.
Posting Guru
Joined: Apr 2004
Posts: 1,342
Likes: 0
From: Georgia
Thanks Fredvon4 I know from my days of working at an auto parts store that some are vacuum to open and some are vacuum to close. I wouldn't want to use a manual setup. I may try this mod soon. It's getting HOT here in Ga. already.
Senior User
Joined: Jan 2005
Posts: 205
Likes: 0
From: Tucson
So I see that they are sold out of this thing, If one were to go to the parts house what should I ask for? is the one they make for the newer trucks compatable?
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Logistics Pro
Joined: Jan 2002
Posts: 3,733
Likes: 38
Go to Ford dealer and take parts guy out to a new 05/06 truck and with the hood up you will see Fords version of this valve it is right on top and very obvious... tell him you want one
Ford is the soucre for several of these vacumme control valves.. in 2001 we were using the one off a Ranger.
Ford uses three different heater hose sizes so be sure you get the right size valve.
If you know what you need Napa and others have this valve cheaper than Ford
Ford is the soucre for several of these vacumme control valves.. in 2001 we were using the one off a Ranger.
Ford uses three different heater hose sizes so be sure you get the right size valve.
If you know what you need Napa and others have this valve cheaper than Ford
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Howdy, Yep you'll need an Orick to open and close the valve..
Senior User
Joined: Jan 2005
Posts: 205
Likes: 0
From: Tucson
Hey all, I think I got all the parts I need to install this Heater Control valve. I got one heater control valve off of a 2002 Excursion from NAPA, 2 hose clamps, 6ft vacume line, and 1 vacume T. Does anyone have instructions or remember how to install DieselSites valve? I cant figure out how to tap into the coolant line, which one at at, and where to tap into the vacume line for the AC control. Anyone?
Thanks in advance!
Thanks in advance!
Mountain Pass
Joined: Jan 2005
Posts: 176
Likes: 1
From: Southeast Texas
Bump
Anyone have any assistance here. I would like to do the same to my truck and would sure like to hear from someone who's done it instead of figuring it out the good old fashioned way.
Pure laziness I reckon!
Come on guys, help us out.
Anyone have any assistance here. I would like to do the same to my truck and would sure like to hear from someone who's done it instead of figuring it out the good old fashioned way.
Pure laziness I reckon!
Come on guys, help us out.
Freshman User
Joined: Jun 2005
Posts: 37
Likes: 0
Interesting thread, I have a problem with my A/C blowing warm at idle. 4.9L 1988 F-150. After flushing the cooling system, changing a thermostat, replacing a fan clutch. It's still doing the same thing, the system was completely checked has a full charge, and no leaks (prior to tossing money).
Could the heater control valve be bad, or the cycling switch. The compressor cycles and and appears to stay on.
Confused
frank1
Could the heater control valve be bad, or the cycling switch. The compressor cycles and and appears to stay on.
Confused
frank1