Hi,
I am new to Hvac!! My Hvac system is acting strangely since the beginning of the summer. The system is a Goodman SSZ14 Heat pump with a Carrier Performance 93 air handler (5 tons both), both has 4 years of age. When I start the day (8Am) on cooling and when it's warm (85+) , my system is building ice (at around 3PM) on the suction line and into the coil inside the air handler. HOWEVER (very strange), when I start the days (8PM) in heat mode (not aux heat) for 10 minutes and then switch to cool mode, there will be no ice for the entire rest of the day. If I leave the system to cool for the next night, in the morning the system will build ice...
What I am trying to says here, is basically, if I don't want ice buildup on the low line, I need sometime in the day, to turn the system to heat mode for at least 10 minutes and then switch back to cool mode... This will make the system work nicely.
Now, I bought a set of gauge and printed some chart with psig to F chart, I came to a subcooling of 4F and Super heat of 34F. I took the temp and pressure measurement at the service valve outside the house, next to the heatp pump unit. I don't know if I should use superheat or subcooling, but did both.
Anyone has an idea of what's wrong ?
Thanks
Super heat : Line press 95 psig - Line temp 64F (if I recall correctly).
Subcooling : Line press 268 psig - Line temp 84F ( if I recall correctly).
I am new to Hvac!! My Hvac system is acting strangely since the beginning of the summer. The system is a Goodman SSZ14 Heat pump with a Carrier Performance 93 air handler (5 tons both), both has 4 years of age. When I start the day (8Am) on cooling and when it's warm (85+) , my system is building ice (at around 3PM) on the suction line and into the coil inside the air handler. HOWEVER (very strange), when I start the days (8PM) in heat mode (not aux heat) for 10 minutes and then switch to cool mode, there will be no ice for the entire rest of the day. If I leave the system to cool for the next night, in the morning the system will build ice...
What I am trying to says here, is basically, if I don't want ice buildup on the low line, I need sometime in the day, to turn the system to heat mode for at least 10 minutes and then switch back to cool mode... This will make the system work nicely.
Now, I bought a set of gauge and printed some chart with psig to F chart, I came to a subcooling of 4F and Super heat of 34F. I took the temp and pressure measurement at the service valve outside the house, next to the heatp pump unit. I don't know if I should use superheat or subcooling, but did both.
Anyone has an idea of what's wrong ?
Thanks
Super heat : Line press 95 psig - Line temp 64F (if I recall correctly).
Subcooling : Line press 268 psig - Line temp 84F ( if I recall correctly).
