I’ve been behind so many techs that have grossly overcharged a heat pump because of a restricted TXV in the cooling mode. If you dump enough gas in the system you can get it to stop freezing but it’s definitely not going to cool very well. Then when it comes time to run the heat the unit keeps going off on high pressure. I once removed over 8 pounds of refrigerant on a system that the factory charge was a little over 6 pounds! Before I ever get my refrigerant off the truck, I’m verifying airflow by checking all filters, the evaporator coil and blower wheel for cleanliness, and most importantly making sure the blower is working and if it’s a variable speed making sure it’s running at the correct speed. The scale always comes off the truck with the refrigerant every time. If I suspect I have an issue with the metering device, I will switch the reversing valve and look at the pressure in the other mode. This can help you determine whether it’s the metering device or possibly low on charge. I work on heat pumps primarily, I’d say about 99 percent of the systems I service and install are heat pumps.
It’s insane how many techs neglect to check filters. I was just on a job the other day that had a filter grill and a filter box at the air handler, both filters were still completely plugged up with sheet rock dust from new construction. Air flow was fucked coil was freezing up and they somehow managed to run a 1/4” liquid line instead of a 3/8s. lol wtf 😂
@ I saw someone saying you can decrease condenser air flow to boost head temperature and that ca help an oil logged evaporator…I was like..i wouldn’t know an oil logged evaporator if I had one…must to learn!
I’ve been behind so many techs that have grossly overcharged a heat pump because of a restricted TXV in the cooling mode. If you dump enough gas in the system you can get it to stop freezing but it’s definitely not going to cool very well. Then when it comes time to run the heat the unit keeps going off on high pressure. I once removed over 8 pounds of refrigerant on a system that the factory charge was a little over 6 pounds! Before I ever get my refrigerant off the truck, I’m verifying airflow by checking all filters, the evaporator coil and blower wheel for cleanliness, and most importantly making sure the blower is working and if it’s a variable speed making sure it’s running at the correct speed. The scale always comes off the truck with the refrigerant every time. If I suspect I have an issue with the metering device, I will switch the reversing valve and look at the pressure in the other mode. This can help you determine whether it’s the metering device or possibly low on charge. I work on heat pumps primarily, I’d say about 99 percent of the systems I service and install are heat pumps.
It’s insane how many techs neglect to check filters. I was just on a job the other day that had a filter grill and a filter box at the air handler, both filters were still completely plugged up with sheet rock dust from new construction. Air flow was fucked coil was freezing up and they somehow managed to run a 1/4” liquid line instead of a 3/8s. lol wtf 😂
Nice information knowledge hvac technician service time following good knowledge
I’d like more information on the oil in the suction line and evaporators in general
Yeah I run into this all the time.
@ I saw someone saying you can decrease condenser air flow to boost head temperature and that ca help an oil logged evaporator…I was like..i wouldn’t know an oil logged evaporator if I had one…must to learn!