TXV

[beenthere]

Whats the indoor wet bulb?

Whats the outdoor ambient?

What the coil delta?

What is the complaint, not cooling at all, or just at higher outdoor temps?

[joe2003]

Originally posted by beenthere
Whats the indoor wet bulb?

Whats the outdoor ambient?

What the coil delta?

What is the complaint, not cooling at all, or just at higher outdoor temps?

indoor wet bulb not taken because txv metering device, od ambient 85-90, I took coil delta but i'm not sure what it was at this time, complaint is unit not shutting off

[beenthere]

With a txv, if you take your indoor wetbulb, you know what your keaving drybulb temp should be.

Does it get to set point but continue to run, or is the temp not coming down?

[joe2003]

[QUOTE]Originally posted by beenthere
[B]With a txv, if you take your indoor wetbulb, you know what your keaving drybulb temp should be.

Does it get to set point but continue to run, or is the temp not coming down? [/B
braburn t-stat 5000, last night temp was 75 t-stat read 75 unit still running. lowered temp to 71 and let run for 24 hours unit got to 72 degrees, raised temp to 74 degrees and unit shut off, i don't think tstat is the problem, again why is subcooling relatively low and superheat low, I still feel that TXV is opening too much, please help.......lol

[beenthere]

For a 14 seer thats not a low subcool.

It is a low super heat.

Is this a swap out, or a new install.

If a swap out, is it the same size as the old unit.

If new was a load calc done.

[bb]

Originally posted by mrbillpro
No!

Wouldn't the air traveling around the bulb cause some differance in the sensing? Or would it be negligable?

[karsthuntr]

Metal is a good conductor of heat, air not so good. The effect of the air would not be noticeable. I never insulate the bulb on walk-in's, and they work fine.

[bb]

Originally posted by karsthuntr
Metal is a good conductor of heat, air not so good. The effect of the air would not be noticeable. I never insulate the bulb on walk-in's, and they work fine.

Thanks. It makes me wonder why Rheems come insulated and they are enclosed.

[dave_slo]

The simplest answer is that insulating the bulb will not hurt anything. It will just ensure that the bulb is sensing the temp of the discharge line of the evap, like it is designed to do.

So if you are looking at it, and questioning whether or not it will make a difference in the unit's operation, slap some wrap on that sucker and see what happens...

[thorton]

Originally posted by joe2003
Does a TXV bulb need to be insulated if it is inside the plenum on the outlet of the evaporator?? I have a new replacement that has low cooling and the unit runs all the time. I spoke of this unit in a post earlier today but didn,t get but 1 reply...lol. If I add r22 to system or take it out my suction pressure stays at 75 pounds. Could the problem be that the bulb is not insulated, it came from the factory like that, should it be insulated?? This is a Tempstar coil.

On my Carrier FV4A fan coil it says the TXV sensing bulb must be insulated on slope coils in horizontal right and downflow applications. Failure to insulate bulb will result in performance loss. Hope this helps

Thorton