Alright guys/gals I would like to get an online diagnosis of my problem. I am a home owner with a 2 year old Lennox 14ACX System. I am not in the industry but have some technical ability. It is currently cooling the house in Houston, TX fine but I had a Tech come out and do a “spring check up” just to see if there was anything wrong with the original install. He found that there was only a 16 degree split when cooling. 71 return and 55 supply when it should be 20-23 degree drop. I have plenty of return air, clean condenser/evap and filters. I will list the technical info below
Log Compressor amps
Condenser fan amps 1.0
Blow ramps 6.6
TXV 39L72 -- TXV kit (R410 a/c) 3.5-5 Ton
Links to direct purchase sites are not permitted.
The technician said that the temp drop was underperforming and the superheat / subcool data was telling us that there is a blockage at the TXV, either stuck in place or there is debris jamming it. The super heat / subcool are obviously both way out of tolearance along with the return and head psi. We checked temps on each side of the filter / drier which is located on the liquid side and they were identical. We popped on a hard start kit to see if that would unjam the TXV and that did not have any affect so we removed it. At that point he said I needed to replace the TXV because the evap was being starved. I decided to do some investigative work myself. I do not have a pressure gauge set but I do have an instant read thermometer. I took a reading on the return side and then stuck it in the supply side. While checking the thermometer I took off all the insulation from the TXV valve and bulb and held the bulb firmly in my hand warming it up considerably. After about 5 minutes I did not see any change whatsoever in the supply temp. Again I have no way of checking the return pressure.
Could the TXV be adjusted? Is this an adjustable TXV?
Do I need to replace this TXV? Am I going to destroy the compressor if I don’t?