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Last year my highest power bill was $320. This month my bill is $598. My outdoor unit is running around the clock. The inside temperature reaches 84F around 2-3pm. It's putting out cool air, but it does not seem to be as cool, or as strong (the air flow) as it was in the past. I called a local HVAC company last month for a diagnosis. He came out and said my coil was probably clogged up with grass clippings. He sprayed it out with the hose. Then he put gauges on it and said everything was fine including the refrigerant levels. I got a bill for $150 but the problem was not solved. Since then I have cleaned the indoor coil. That did not help. I used a fin comb to straighten any that had been bent. No change. The compressor does not seem to have any issue starting, and seems to run continuously. What can I check for now? The unit was installed in 1998 I believe.
 

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First find another company that will check both the indoor & outdoor unit. What is the temp at the supply & return? Also, is your fan running at the highest speed. Another is, where are you located, the tonnage of the outside unit (if do not know, post model# of both indoor & outdoor, with manufacturer). Did the tech write down the Super Heat & Super Cool when they checked with the gauges, and pressure? Also, how old are both units, do you have drapes closed on all windows, air leaks sealed at doors, windows, outlets & switches, and how well is the attic insulated (aprox depth measured with a ruler if blown. All of these factors can account for improper cooling.
 

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First find another company that will check both the indoor & outdoor unit.
I'm in a small town. There's only one local. I can get a guy out of another town but they charge a pretty high trip charge.
What is the temp at the supply & return?
I'm guessing you mean at a ceiling vent and at the filter where the air is sucked in?
Also, is your fan running at the highest speed.
As far as I know it only has one speed. And yes it seems to be running at full speed
Another is, where are you located
Central Alabama
the tonnage of the outside unit (if do not know, post model# of both indoor & outdoor, with manufacturer).
Outside unit: RPKA-030JAZ Inside unit: RCBA-3765GG17
Did the tech write down the Super Heat & Super Cool when they checked with the gauges, and pressure?
No I'm lucky he had time to speak to me. He was too busy talking on his cell.
Also, how old are both units
It was replaced around 1996-1998 i think.
do you have drapes closed on all windows, air leaks sealed at doors, windows, outlets & switches
Yes. I have sealed every possible leak I could find. I even had ridge and soffit vents installed last year. That was supposed to help keep the house cooler this summer.
and how well is the attic insulated (aprox depth measured with a ruler if blown. All of these factors can account for improper cooling.
12 inches
 

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The ridge vent? No clue. The insulation doesn't go that high anyway. The soffits on the front are on the front porch which runs the entire length of the house. There is a dam that keeps the insulation out of the porch area. So no insulation could get to that anyway. (In other words the insulation only covers the indoor part of the ceiling.) I'm pretty sure there was something additional installed with the rear soffits though.
 

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I suggest you call the service guy back.You called with an insuffient cooling complaint.He charged you to fix that complaint,and you still have the same problem.Call him and tell him you paid to have a problem fixed and you still have the same problem so what did you pay for.Tell him you expect it to be fixed.
You are well within your rights to expect that he fix the problem that you have paid to have fixed.
Do not let him leave without giving you the super heat or the sub cooling numbers.
If you post back to this thread please give us the temp at the supply register and at the return grille.Then give us the tempatures just before the inside blower and just after the inside coil.Believe it or not you can use a cooking thermometer for these mesurements.
 

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You still need the baffles at the soffit vents, to allow proper air flow, and to also make sure insulation does not migrate over time over them. As for the hvac system, find a reputable guy, or company that can come over and do a good through check on the system. You can also run the manual J calculator from http://www.hvaccalc.com/main.asp to make sure that your current system is sized properly for the house.

Things you can do, has already been explained previous, as for the system fan, you can go and look in the furnace to make sure the fan is set on high for cooling, which should be on the schematic on the access panel for the blower, or in the instruction manual. Get a thermometer and take the air temp from the nearest supply from the furnace, and the return. Also post the thermostat setting for indoor air temp that you are wanting it to achieve. Another thing you can do, is make sure the duct work has no leaks, and if insulated flex-duct, make sure it is the straightest it can, and that metal duct was used for the turn to the vent.
 

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For the description of your problem. The AC was working correctly. I think your system is running under charge. Since the coils are clean.
 

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Discussion Starter #9
You still need the baffles at the soffit vents, to allow proper air flow, and to also make sure insulation does not migrate over time over them. As for the hvac system, find a reputable guy, or company that can come over and do a good through check on the system. You can also run the manual J calculator from http://www.hvaccalc.com/main.asp to make sure that your current system is sized properly for the house.

Things you can do, has already been explained previous, as for the system fan, you can go and look in the furnace to make sure the fan is set on high for cooling, which should be on the schematic on the access panel for the blower, or in the instruction manual. Get a thermometer and take the air temp from the nearest supply from the furnace, and the return. Also post the thermostat setting for indoor air temp that you are wanting it to achieve. Another thing you can do, is make sure the duct work has no leaks, and if insulated flex-duct, make sure it is the straightest it can, and that metal duct was used for the turn to the vent.
I'll go out and buy something to check those temps.
 

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Discussion Starter #10 (Edited)
For the description of your problem. The AC was working correctly. I think your system is running under charge. Since the coils are clean.
Yes it was running fine last summer. The problem started when I first turned it on this year. Only one change has been made since then. The heating elements in the air handler were replaced in January.

I will say this. I didn't run heating or AC during the spring. When I first turned the AC on this year, I noticed a strong odor coming from it. An odor similar to what I smell when I turn the heat on for the first time in the winter. I have never noticed that before. I ran outside to make sure the unit was ok.
 

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Do you have a separate breaker for the electric heating elements, if so I would shut it off to eliminate unwanted heating as a possible cause.

Two years ago I had a relay fail on my ground source heat pump, the contacts arced, stuck together and caused the heating elements to stay on even when the unit did not call for heat. If you could smell the elements when you first started the AC you may have a similar issue. The odor of coils heating up after a period without use is very distinct. This could also explain why the unit checked out OK but still can't keep up.

If you don't have a separate breaker you could turn the AC off, run only the fan and check the temp of the air coming out the vents. A more reliable method would be to test for voltage or amp draw at the heating coils while the AC is running.
 

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Hmmm heat smell with the AC on could be an element stuck on. Pressures would look normal but an additional 15,000 btu load on an AC is hard to overcome.
 

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Heat strips may have been mis-wired, and one of them is coming on with the A/C.
 

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I've disconnected the heating elements and taped them off. The relay seems to be in bad shape. I will see if there is any difference. They were hot to the touch when i opened it up.
 

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Good news. I'm down to my thermostat setting and my unit shut off. :thumbup:

I'm going to try replacing that relay to see if the issue is fixed. Anyone know where I can find a part number for it? I cant see one on it anywhere.
That section has the model number: RBHA-17J10SFDA
 
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