Cooling troubles.

[SixStringMadness]

I have a Carrier 8000 weather maker, 58WAV091-14114

I replaced the blower motor and capacitor, due to very low air flow.

Now the unit blows, but the difference in air inlet and outlet temps is 10 degrees or less depending on which vent I check, and is having a difficult time bringing the temp down in the house. I'm trying to get to 74, but can't seem to get below 78. Outlet temps average 66, and inlet are about 76.

The condenser/compressor unit is new (previous owner) maybe 2 years old, but the Carrier unit is 10+ years best guess.

Any assistance is appreciated. I'm one of those guys with well rounded mechanical skills, and generally fix most items in my home or driveway...

 

[kokomochandler]

a big problem with not dropping temps as long as the freon is full is the evaporator core fins either being full from dirt by using crappy filters or the fins deteriorating and restricting air flow.

it works just like a car. all it does is take the hot air in the house run it across the evaporator and tranfer it to the freon . take it outside and the fan pulls the heat out of the freon at the condenser. pretty simple but if the the evaporator core in the house gets clogged the hot air cant be tranferes across. same outside if its clogged the fan cant pull the heat out so it builds up and up. a set of gauges will easily tell you whats going on cheap gauges are ok if your not going to use them on a daily basis.

my evaporator core is getting clogged so mine is running all the time. my st bernard and lab dont help with dog hair getting into the filter all the time. it will also hurt furnace flow as the air travels thru it to get to the heat ducts so it makes the furnace fan harder to push the heat thru.

 

[General Lee]

Have the coolant checked, sounds like its low. Have you noticed anything lines or coils freezing up? Large copper line from the indoor coil to outdoor unit should cold, thin copper line should be warm, not HOT. If they are not, coolant problem or air flow problem.

 

[SixStringMadness]

Okay, I've allowed the unit to run for about an hour and I have now noticed the large copper line is freezing where not covered with insulation. It was not doing this with the old blower motor yesterday. I looked inside the condenser (outside) and the compressor was starting to freeze also. I have now powered the entire system down.

It appears, that to reach the coils inside I will have to tear apart the duct work on top of the furnace unit in the garage. Is this standard practice?

 

[lzenglish]

I wrote a long winded response to your original post, and now I see your latest one. I think you may have wired your blower motor to run backwards. If the coil was not plugged yesterday, (no Noticable Icing on the suction line), then I doubt if it plugged up over night. Also, some motors have 3 speeds, make sure yours is on the proper terminals to get the correct amount of rpm. If you need to access the evap coil, there is usually an inspection plate on the side. BUT, Before you do that, see if your squirell cage is running in the correct direction, and speed first.

Wayne

 

[General Lee]

After you try what LZ suggested and if everything checks ok, you are low on coolant. Gotta be. Before you made the repairs, even though you had low air flow did you have cooler air from the vents? Sub par temps from the vents is usually one of 3 things: Low coolant, poor airflow (dirty coils, filters) or a bad expansion valve.

 

[SixStringMadness]

I wrote a long winded response to your original post, and now I see your latest one. I think you may have wired your blower motor to run backwards. If the coil was not plugged yesterday, (no Noticable Icing on the suction line), then I doubt if it plugged up over night. Also, some motors have 3 speeds, make sure yours is on the proper terminals to get the correct amount of rpm. If you need to access the evap coil, there is usually an inspection plate on the side. BUT, Before you do that, see if your squirell cage is running in the correct direction, and speed first.

Wayne

I appreciate your input, I do, but of the HVAC things I could screw up, the electrical portion is not one of them. It will **** the air filter in both returns right out of you fingers. I did not wire the fan backwards, nor reverse any of the speeds.

After you try what LZ suggested and if everything checks ok, you are low on coolant. Gotta be. Before you made the repairs, even though you had low air flow did you have cooler air from the vents? Sub par temps from the vents is usually one of 3 things: Low coolant, poor airflow (dirty coils, filters) or a bad expansion valve.

We have not used the AC all that much this year as I have a fair amount of tree coverage. When it did run, I felt like it ran too often. The condenser unit sits right outside my office window and blows around a large rose bush, so it caught my attention each time.

I guess it was sufficient, but never impressive would be my description...

 

[lzenglish]

I appreciate your input, I do, but of the HVAC things I could screw up, the electrical portion is not one of them. It will **** the air filter in both returns right out of you fingers. I did not wire the fan backwards, nor reverse any of the speeds.

Great! Now, are you getting a good supply air flow out of your registers?

 

[SixStringMadness]

Great! Now, are you getting a good supply air flow out of your registers?

I would like to give you an answer of such and such psi or flow rate, but my answer is completely subjective. It's better than it was.

Upon removal of the coils inspection panel, with the unit running, the air coming out is quite chilly. Enough to make me want to go put a shirt on.... But my air split inside is still below 10 degrees.

Here is a picture of the coils. I would imagine that if I were to clean the coils though, it would be the underside, which would require removal of the furnace exhaust fan to access the portion of the AC coils. Looks easy enough, I don't have to fool with any gas lines, but it appears to be glued in as well as screwed in. What type of glue is that?

 

[philip_g]

if the suction line is freezing likely the coil is freezing as previously mentioned.. The 2 causes of a frozen coil are low on refrigerant or lack of airflow. If your filters are good and you're positive you wired the motor correctly, and to run on high speed when AC is on I'd say it's the charge. So, either you're low on charge and it's causing your lack of airflow or your lack of airflow is causing it to ice up. Let it run a bit and post a pic of the suction line out at the unit at the service valves, I'm curious..

You don't need to remove the coil to clean it. ZEP and others sell chemical coil cleaners that will handle it. Grainger sells it for about 10 bucks.

My money is on a miswired fan motor, they're multiple speed motors.

the goop on the gas line isn't glue, it's pipe dope.

 

[SixStringMadness]

I'm not talking about the gas pipe, I'm talking about between sheet metal. The exhaust fan housing, and removing it to get to the underside of the coils to clean them.

As far as the motor goes, the red wire says high speed, and it terminates on the cool terminal of the control board, just like the one that I removed, and I would be considered an expert in the electrical field. I think I have that covered, and correct.

Here a shot of the gauges, can someone assist me with interpreting what this means?

The manufacturer tag says factory test pressure, low 150, high 300.

It's a Goodman CLJ42-1C outdoor condenser unit.

 

[Mike007]

You are low on refrigerant.

 

[philip_g]

Look at the inside of the service panel, there should be a charge chart for the pressures based on temps.

Just because you wired high to high and low to low doesn't mean that furnace wasn't a 4 ton blower and you put a 3 on it.

 

[acmikee]

the refrigerant is 410. if yes you are low on charge. look for an oil stain on the cond coil. get some soap and soap up around the brazed joints, the bottom joints in the indoor coil and the mettering device in the indoor coil (the nut w/tubes coming out).

 

[SixStringMadness]

At this point I just got tired of guessing, and found a guy to come out. He added 3 pounds of R22 for $150.00. I'm a little concerned he didn't look for a leak, even when I questioned him about leaks, but for now the temps are dropping inside, I'm taping the air leaks on the coil box, and we'll wait and see how it goes....

 

[JakeKohl]

I'm not talking about the gas pipe, I'm talking about between sheet metal. The exhaust fan housing, and removing it to get to the underside of the coils to clean them.

As far as the motor goes, the red wire says high speed, and it terminates on the cool terminal of the control board, just like the one that I removed, and I would be considered an expert in the electrical field. I think I have that covered, and correct.

Here a shot of the gauges, can someone assist me with interpreting what this means?

The manufacturer tag says factory test pressure, low 150, high 300.

It's a Goodman CLJ42-1C outdoor condenser unit.

These gauges indicate you are low on refrigerant. In a rough generalization, you want to see the suction temperature around 40 degrees on an R22 system (assuming this is what you have). If you look at the green part of the low side dial, at 40 degrees, the low side pressure will be around 70psi. Also in a rough generalization, you want to see the high side temperature about 20 degrees above outdoor ambient air temperature...so if it's 80 degrees outside, you want to see a high side temperature of roughly 100 which translates to about 95 psi. Temperatures and pressures with different types of refrigerant are vastly different scales.

Because the system is low on refrigerant, the system is cooling below freezing at the evaporator in the house. Because of this, the condensate on the evaporator turns to ice...which, consequently, blocks the evaporator and will reduce air flow. Reduced air flow leads to lower evaporator temperatures and more blockage...hence, your evaporator was probably half solid with ice and your blower was probably fine.

 

[JakeKohl]

At this point I just got tired of guessing, and found a guy to come out. He added 3 pounds of R22 for $150.00. I'm a little concerned he didn't look for a leak, even when I questioned him about leaks, but for now the temps are dropping inside, I'm taping the air leaks on the coil box, and we'll wait and see how it goes....

Leaks are sometimes very difficult to find - if they can be detected at all. Given that you still had a good bit of refrigerant in the system, it's possible you have an extremely minor leak. If you have to recharge the system within the next year, a leak check would definitely be warranted.

 

[SixStringMadness]

These gauges indicate you are low on refrigerant. In a rough generalization, you want to see the suction temperature around 40 degrees on an R22 system (assuming this is what you have). If you look at the green part of the low side dial, at 40 degrees, the low side pressure will be around 70psi. Also in a rough generalization, you want to see the high side temperature about 20 degrees above outdoor ambient air temperature...so if it's 80 degrees outside, you want to see a high side temperature of roughly 100 which translates to about 95 psi. Temperatures and pressures with different types of refrigerant are vastly different scales.

Because the system is low on refrigerant, the system is cooling below freezing at the evaporator in the house. Because of this, the condensate on the evaporator turns to ice...which, consequently, blocks the evaporator and will reduce air flow. Reduced air flow leads to lower evaporator temperatures and more blockage...hence, your evaporator was probably half solid with ice and your blower was probably fine.

Leaks are sometimes very difficult to find - if they can be detected at all. Given that you still had a good bit of refrigerant in the system, it's possible you have an extremely minor leak. If you have to recharge the system within the next year, a leak check would definitely be warranted.

Good info, thanks for the help!