Troubleshooting HVAC

It does, but the meter defaults to continuity first on the ohms setting and I have to hit the SEL button to read resistance. I believe I have to hit the button while the leads are attached, which is difficult by yourself. I could be wrong. Its an IDEAL 61-347.

 

I wish my meter had them separated out like yours does. That would be much easier.

 

That's not mine, it's just a random picture of one I found with labels but pretty much every meter I ve seen even the dirt cheap ones have resistance and continuity separated.

 

100% Correct. I plugged the temp sensor back in and jumped the pressure switch. I have A/C now. Can this damage anything by running it this way short term with the sensor jumped? I won't have time to tear it apart until next week and A/C would be nice.

 

That depends, if the system is low and you run it, yes there can be damage. I do not read where you have put a set of gages on it, have you? If so, what is the static pressure, with the system off they should read the same and close to ambient air temp. In operation with a proper charge, 30 ish on the low and 175- 225 ish. I say ish because temperature affects pressures in AC.

 

No I have not put gauges on the system. I had the system charged at a local shop. They put dye in so if there was a leak I hope I would have seen it.

 

Refriderant dye, nooooooo. Unless there has been a change, as far as I know the dye damages the AC shops extraction equipment and other shops might not work on your AC knowing that.

I dont know how to answer your inquiry as to if you can run the system with the low pressure switch bypassed, Toyota put it in there to protect the system from running with low pressure. As the refriderant flows through the system it carries lubricating oil with it so running with low pressure means low lubrication, your call.

 

I appreciate your answer, I'll just have it evac'd as soon as I can. In the meantime I'm going to try and build a simple test rig for the switch so I can check its function off air pressure.

 

As long as you don't have a situation where the refrigerant leaks out or thebhead pressure goes through the roof you should be fine for a bit.

Dye is fine as long as it's just dye, most A/C systems nowadays have factory dye anyway.

Problem is alot of those "quick charge" cans have stop leak in them and sometimes dye too. Stop leak is the worst thing you can put in an A/C system.

 

Well I was going to just run it and then the fellow who charged it told me to swing by and he could drain the system real quick. Turns out the belt was loose and squealing so I had him drain it. Off to Lowes to come up with an adapter to mount this sensor to my compressor so I can test it.

When I put in the new evap coil, the oil I got was green so I guess that was similar to the factory dye.

 

Your fine with that, the only time I've seen dye mess up a system is when somebody kept stuffing dye into one because they couldn't find a leak.

Stop leak on the other hand will wreck a system if any moisture or air ever gets in and alot of those cans you find on the shelf at random stores have it in there.

 

I stand corrected... dye ok stop leak not.

 

Yea, at least I've never seen any damage from dye other than like I said if you get an extreme amount of it in there or somehow mix two incompatible dyes.

Dye is great for finding leaks, I was glad when they started adding it at the factory.

 

So I got the evap box out again and sure enough I did not connect the pressure sensor to the pigtail. So with that mystery solved I also discovered that the heater door would not open all the way. The bottom pivot was a bit rusty so I lubed it up. The issue was/is the heater valve cable. It was so stiff, when I disco'd it the heater door opened right up. I dropped some oil down the end and it got better but I may need to swap out the cable. Anyways I'll have the system recharged on Tuesday. Thank you folks for all the help.