Jump to content

Flt deck temp control problem


Davidson88
 Share

Recommended Posts

How is it going? I work at the depot and we are have a issue that has stumped us so I'm hoping someone out there has had this issue before. On a 65 model our temp control wants to migrate back to cool when pressurizing in manual while driving hot. We have changed the temp control valve, flow control, thermostats, control boxes, and pressure controller but nothing seems to fix this problem. We can only get to three inhg on the ground. The electrics shop has shot the wires and says they are good. We put a 240 degree thermostat in the unit and the unit wouldn't drive hot so we tried it with the thermostat still hooked up but pulled out of the unit and it drove hot. The engineers say that the 240 thermostat is the right one for that model. Can anyone shed some light on this subject for me. Thanks

Link to comment
Share on other sites

I worked an aircraft a while back with cargo air going full hot in auto and manual. We did the same changed everything we even went so far as to re-wire from the temp control valve to the control box (spliced in the wires didn't have CP) still the same problem when the NEW cannon plug was installed it fixed the problem. The wire all checked good prior to replacing them.

Another thing is make sure the thermostats (we used a jetcal tester) are working properly. We had a rash of 100 or so bad a few years back.

Link to comment
Share on other sites

This stupid thing will not do the samething twice. We get working right then it does something totally different. Today our flt deck PAC started working in manual but wouldn't work in auto then our cargo PAC drove to cold but when we tried to drive to hot nothing would happen shot the plug and now we have 28 volts on both hot and cold. The fi tells us to connect a temp control test box and it seems that no one knows where to get one has any one used this tester

Link to comment
Share on other sites

That tail left before I got here!!

I does sound familiar with what we dealt with for cargo air. The anticipator stats were the ones that were coming in bad (forgot to mention with stat).

We would turn cargo ac on an then you could watch the valve got to full hot every time. This drove a rewire and CP change. (we used a known good stat to confirm that was not the problem):cool:

Link to comment
Share on other sites

This stupid thing will not do the samething twice. We get working right then it does something totally different. Today our flt deck PAC started working in manual but wouldn't work in auto then our cargo PAC drove to cold but when we tried to drive to hot nothing would happen shot the plug and now we have 28 volts on both hot and cold. The fi tells us to connect a temp control test box and it seems that no one knows where to get one has any one used this tester

Jason,

The NSN for the tester is 4920-00-014-1504, but at $72,520.00 I belive you are going to have a hard time acquiring one. Lockheed Martin has them...

Your neighbor

Link to comment
Share on other sites

Remove "pressurization and Air conditioning" from the same sentence. The only common point would be the AC Press Master switch. Make sure the wires on the back are tight...

Jump both of your temp control boxes. B to E and then C to F.

This will remove all the voltage sources except the manual temperature control.

Be carful as you do not have any duct protection.

If the valves respond to your temperature switch then your basic system is operable.

Then you can tshoot the control system.

Link to comment
Share on other sites

  • 2 weeks later...

B-E and C-F . Yes "Big Ethel Can F" does anyone remember any others for the jump out cheats, or t/s tricks.

Just curious, probably should be another thread.

(B)ad (B)oys ®avish (O)ur (Y)oung (G)irls (B)ut (V)iolet (G)ives (W)illingly

Link to comment
Share on other sites

  • 2 weeks later...

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share

×
×
  • Create New...