Defrost Setting
1 - 7 of 7 Posts
kenmac states: "as far as I know it's set up by each manufacture & operates through the sensor / defrost board"
Makes sense and I agree with that. I would think that climate conditions would determine the settings and looking to understand how the actual time settings are made and if it is feasable to increase from 60 to 90 minutes.
Makes sense and I agree with that. I would think that climate conditions would determine the settings and looking to understand how the actual time settings are made and if it is feasable to increase from 60 to 90 minutes.
Joined
·
1,517 Posts
On most defrost boards there are a series of jumpers to either increase or decrease defrost time from 30,60,90
Defrost happens when the sensor on the suction line reaches (I think) approx 27 deg. The unit will go into defrost until the temp is raised to a spec temp and return to heating. If you notice long defrost cycles you may be low on charge or the temp outside my be really low. Most of the time I have seen that 60 mins are fine.
If you still have the installation instructions this would be a good place to start
Defrost happens when the sensor on the suction line reaches (I think) approx 27 deg. The unit will go into defrost until the temp is raised to a spec temp and return to heating. If you notice long defrost cycles you may be low on charge or the temp outside my be really low. Most of the time I have seen that 60 mins are fine.
If you still have the installation instructions this would be a good place to start
Joined
·
42,671 Posts
Your winter ambient conditions determine defrost timer setting.
High humidity ares, may need 45 minutes, dryer areas can use 90 minutes.
See how frosted your outdoor unit is when it goes into defrost now.
If its getting heavy, then 90 minutes will be too long. And you won't get much heat for the last 30 minutes of compressor run time.
And will end up using aux heat more then needed.
High humidity ares, may need 45 minutes, dryer areas can use 90 minutes.
See how frosted your outdoor unit is when it goes into defrost now.
If its getting heavy, then 90 minutes will be too long. And you won't get much heat for the last 30 minutes of compressor run time.
And will end up using aux heat more then needed.
While the manufactures do consider many climates, the final factory settings are a guess to do no harm for all climates. Now that you know it might be too short for your climate you could try changing it. If you are considering a longer timer setting let us know how that changes your energy consumption and performance.
Winter humdity levels are somewhat high here in eastern NC with the exception of January and February which can have humidity levels in the low 20°'s. As far as frost build up, I have only noticed during one mini snowstorm and possibly a couple of rain storms with low temps. I never noticed any severe frost. And for these reasons and a now better understanding of the defrost cycle, it is probably best to leave the setting of 60 minutes right where it is.
1 - 7 of 7 Posts
