[bob22]

New a/c unit.
Should the one line in the picture have more insulation on it?
I noticed when unit is running that both tubes seem cold. Shouldn't one be warm/hot and the other cold?
Thanks,
Bob

 

[Marty S.]

That missing cap on the suction valve is a bigger problem then the missing 6" of insulation. Call the installers back and make sure they check the subcool or superheat according to the directions. The little line should not be cold.

 

[yuri]

The small liquid line should be warm and the big one should be cool. (general statements depending on where you live, outdoor temp and humidity, heat load in house etc). Older units used to run where the big one/suction line was COLD and sweating and the small liquid line could get warm to hot. The newer higher SEER units don't go to those extremes. A bit more insulation would help but is not necessary. Most important part is that the installer checked the operating pressures and superheat or subcool depending on what system you have.

 

[bob22]

Thanks all. So the missing cap can lead to leakage? This was done about 3 weeks ago. Is this enough time for sufficient leakage to have occurred to demand that they check operating pressures and superheat/subcool? Should I assume the unit has a low pressure cut-off to prevent damage to compressor if it goes too low (a new York unit)?

 

[Marty S.]

Schrader valves are not supposed to leak but sometimes they don't seat correctly. Checking the charge with SH/SC is standard procedure so ask them to check it and note the results on the service ticket along with the factory recommendation. Techs get paid to keep customers satisfied with the company service and we'll gladly do it, shouldn't be any need to demand.