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How can refrigerant be low on one day, but ok on anther day
When the indoor temp is down near normal set point, and the outdoor temp is not real hot. Its possible for the SH and SC to be in allowable range. But when checked when the indoor temp and or outdoor temp are hot, the low charge show up.

Can also be, the tech made a mistake on either day.We aren't perfect.
 
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Discussion Starter · #23 ·
When the indoor temp is down near normal set point, and the outdoor temp is not real hot. Its possible for the SH and SC to be in allowable range. But when checked when the indoor temp and or outdoor temp are hot, the low charge show up.

Can also be, the tech made a mistake on either day.We aren't perfect.
Even a non perfect AC technician would first look for a leak, before charging me $500 for refill, as it will leak out again anyway.
I think the probem is in my thermosat. I need one of those that keep running the fan after the compressor was turned of (Fan off delay). As it is right now the compressor and the fan are turned off at same time. The heat exchanger coil is still cold, and ice will build on it without fan blowing.
Right or Wrong ?
 

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Even a non perfect AC technician would first look for a leak, before charging me $500 for refill, as it will leak out again anyway.
I think the probem is in my thermosat. I need one of those that keep running the fan after the compressor was turned of (Fan off delay). As it is right now the compressor and the fan are turned off at same time. The heat exchanger coil is still cold, and ice will build on it without fan blowing.
Right or Wrong ?
Wrong
 

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Even a non perfect AC technician would first look for a leak, before charging me $500 for refill, as it will leak out again anyway.
I think the probem is in my thermosat. I need one of those that keep running the fan after the compressor was turned of (Fan off delay). As it is right now the compressor and the fan are turned off at same time. The heat exchanger coil is still cold, and ice will build on it without fan blowing.
Right or Wrong ?
Wrong
 

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Even a non perfect AC technician would first look for a leak, before charging me $500 for refill, as it will leak out again anyway.
I think the probem is in my thermosat. I need one of those that keep running the fan after the compressor was turned of (Fan off delay). As it is right now the compressor and the fan are turned off at same time. The heat exchanger coil is still cold, and ice will build on it without fan blowing.
Right or Wrong ?
Incorrect. The coil begins to warm up as soon as the compressor stops running.
 

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Hello! When our central AC system started to be low on refrigerant it would have times that the air flow was poor in the rooms and other times when it was not. When the airflow is low, take a look inside the air handler and you will see that the coil is frozen over, which restricts air flow.

What happens as the refrigerant gets low is that the coil temp begins to drop too low and causes water in the air to freeze on the coil. It's the opposite of what you would expect, but that is what happens.

After the coil warms up when the unit is off and the ice melts, then air flow is fine the next time the AC goes on.

The reason for low refringent is always a leak, and it's really expensive to fix. If your units is older than 10 years and no longer has a part warranty, it's better to start looking for a new system.

Since you did not trust the first tech, get another opinion by a different company, and see what they say.

Hope that helps!
 

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Even a non perfect AC technician would first look for a leak, before charging me $500 for refill, as it will leak out again anyway.
I think the probem is in my thermosat. I need one of those that keep running the fan after the compressor was turned of (Fan off delay). As it is right now the compressor and the fan are turned off at same time. The heat exchanger coil is still cold, and ice will build on it without fan blowing.
Right or Wrong ?
For some technicians, everything they do is a la cart. One would think that in this day and age, along with EPA laws and rules in the US, that if a tech finds a system in need of an estimated 4 pounds of R22 or even R410a, that they would recommend a leak search.

There are obviously those that do not, many on youtube and in your area! A good tech is hard to find. Like any profession, there are good and bad! We were not there so we dont know exactly what he did, didnt do or recommend prior to the recommendation of 4 pounds of refrigerant.
 

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More like the customer doesn't have good listening skills.
Sorry, I'm from the era when the teacher is at fault if the student doesn't understand.
 

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How can refrigerant be low on one day, but ok on anther day
You ever looked at a P/T chart? You even know what one is? Pressure and temperature with regards to refrigerant have a correlation. At one temperature you will have x pressure, and at a different temperature you will have y pressure. If he checked your charge on a 90° day and had an evap coil temp of 38° and then the next week the temp outside dropped to 75°, I would expect a coil temperature below freezing. If you hire a QUALIFIED tech he will know these things which you obviously do not.

Something as simple as an extremely dirty filter can look like a refrigerant leak to an inexperienced tech.
 

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Discussion Starter · #34 ·
You ever looked at a P/T chart? You even know what one is? Pressure and temperature with regards to refrigerant have a correlation. At one temperature you will have x pressure, and at a different temperature you will have y pressure. If he checked your charge on a 90° day and had an evap coil temp of 38° and then the next week the temp outside dropped to 75°, I would expect a coil temperature below freezing. If you hire a QUALIFIED tech he will know these things which you obviously do not.

Something as simple as an extremely dirty filter can look like a refrigerant leak to an inexperienced tech.
What is Qualified tech ?
How do they differ from not qualified?
How am I going to determine that, without been expert in HVAC my self.
Reading P/T charts, are you kidding.
 

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Discussion Starter · #38 ·
If you're not going to do it yourself, and you don’t trust the tech that came out because you “ran him off”, who’s going to fix the issue?
You are avoiding to answer my question.
What is Qualified tech ?
How do they differ from not qualified?
How am I going to determine that, without been expert in HVAC my self.
 
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