how could he have 14SC and 12SH with no way of measuring??
My Service tech moved the TEV bulb mounting from horizontal to a Vertical position on the suction line. He told me that in the horizontal position it was too close to the TEV pressure line. He stated 3 inchs of space needed.
He was never able to achieve the factory specs of 7 to 9 degrees on the sub cooling and 7 degrees on the SH. Even though he adjusted the TEV to wide open. He ended up with 14 on the SC and 12 on the SH.
I was reading the instructions from the TEV and it is saying to only mount in the Horizontal position and only at 10 oclock or 2 oclock position
What do you experts say about this. I have now had three service guys out in the last year. None of them even had a proper way of measuring the SH and SC.
And yes, all of them where NATE certified.
how could he have 14SC and 12SH with no way of measuring??
The sensing bulb should always run with the suction line. If the cap tube is too close to the Liquid line he needs to remove the bulb and pull some slack from coiled up cap tube that connects the bulb to the valve and get the clearance and secure it back to the suction line. Hope he has the bulb tight and insulated. Not a complicated job. Did he bother checking airflow across the coils, dirty filter/evap/condenser before adjusting the Valve? How are you determining they have no proper way to check the SC/SH?
Never mind my last sentence on the SC/SH... no way he should be using an IR no contact meter for determining the actual temps. sigh...
Call the company back and explain to the manager what was done.
BTW, I forgot to mention about the bulb position. The bulb basically has a liquid refrigerant in it. the reasoning for the bulb to be mounted between 10 - 2 is to prevent liquid from blocking the cap tube thus requiring more pressure to push the liquid through the cap tube resulting in inaccurate adjustment from the power head.
You seem to be very concerned about SC and SH but you didn't mention in your post what the problem is that you are having with the system. You have had 3 techs out in the last year you say. Why?
Why are these guys adjusting the TXV wide open? Why are they moving the bulb? What is the system doing/not doing?
Knowing the problem and symptoms would really help us out here.
"If you aren't living on the edge, you are taking up to much space!"
An IR thermometer isn't accurate enough to know what SC and SH the system really has.
liquid in the buld should never cover the cap tube inlet of the bulb and the Sensing bulb should never be on the liquid side of the suction line.. At least that is all I have ever read and was taught.
Didn't think that bulb placement was a DIY infraction. Sorry
I agree with jpsmith1cm. He has more issues than the bulb. I would suggest the tech's being sent are one of them. No way he is getting anywhere close with IR no contact temp equipment for SC/SH.
Yep ......... back to post #6. OP what is the problem ?
The original problem was low Delta T across the evap.(8 degrees) But now problem is solved and all I can tell you is NOT to mount the TXV bulb Vertical on The suction line. Placement of bulb was correct to begin with.
To answer everyones questions. The CFM is correct and the SP is correct. The original problem was not a correct charge to begin with. Unit insalled in December and believe me when I say the factory charge must have been way off. Sight gauge was clear and that is what they left it at.
Without a correctly functioning TXV, it is impossible to correctly charge a unit.
Without the correct airflow it is impossible to correctly charge a unit.
Without the correct instruments, it is impossible to determine proper TXV function, proper airflow, OR proper charge.
If your techs were using an IR thermometer to guess at line temps, I can only imagine what sorts of guesses they made at airflow.