A/C freezing up...


  #1  
Old 07-10-01, 05:18 AM
Goodwrench
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Unhappy

Bought a house with an A/C unit & it seems to act up quite a bit. At first it would run cool then the air would blow room temperature. Called in a repair guy & he claimed the freon level was way too high. Thus he bled the system & everything was O.K. for a day. Now the air blows cool, not cold, and within hours the lines outside freeze over & the air flow is next to nil. The filters are clean & we cleaned the " A " coils last nite. It greatly improved the air flow ,but again after a few hours it freezes up & the airflow trickles. Any thoughts would be greatly appreciated...thanx in advance
 
  #2  
Old 07-11-01, 07:04 PM
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Talking a/c freezing up

When A/C systems freeze up, usually the culprit is airflow or a low freon charge. Having purchased your house with an existing system, you have no idea what service has already been done, or that the components are correctly sized, i.e. a 2.5 ton condensing unit with a 2 ton evaporator. Or the installer may have chosen an improperly sized orifice for the metering device. I hate to assume, but let's say the units are correctly sized for each other with a proper orifice......And, considering that your airflow i.e. fan is runnig at proper RPM's and duct system is free of obstructions.........I would reclaim all refrigerant from this system. Change out the filter dryer. Check for leaks w/ dry nitrogen. Triple evacuate the sytem till it would hold a vaccum of around 300 microns. Then I would re-charge the system with the manufacture's recommended amount of refrigerant. If all the duck's line up, you should be cool as a cucumber. Please contact a REPUTABLE HVAC servicer, let me know if he agrees. Have a good one...
 
  #3  
Old 07-12-01, 04:31 AM
Goodwrench
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Cool

Thank you for the info. I will let you know how it turns out.
 
  #4  
Old 07-16-01, 05:07 AM
Goodwrench
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Cool

It seems that I was low on freon & a leak is suspected. Because the "A/C guy" purged freon from the system the previous week, he added some to the system to get it working correctly. He also told me that it could cost around $1000 to remedy a leak. Doesn't seem worth it to me. Surely replacement would be a better option. Two questions though. Could a clogged "A" coil cause a false reading with regards to the amount of freon in the system? Secondly, I'm currently electric & pondering switching to gas. Furnace & A/C. Being a new home owner not sure if this would be a wise move or not. The furnace is about 9yrs. old & the A/C unit is about 23yrs. old. Should I switch or not? Thanks in advance for your thoughts...
 
  #5  
Old 07-16-01, 06:50 AM
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Talking A/C problems

$1000.00 to repair a leak. That is quite an estimate. Has it been determined where the leak is? If not, I guess I would think that your "serviceman" is trying to lean you towards some new equipment. Which may not be a bad idea considering the age of your equipment. If you do decide to change out your system, make sure your new system has high SEER ratings "10" or above. the higher the rating, the less it will cost you to run it. Alas, initial cost will be more. The price for efficiency.....A second opinion/bid may be in order, ...your choice.........
A-Coil being plugged (I am talking now about on the outside of your coil dirt, dust, whatever). will cause a lot of trouble. Airflow obstruction (dirty coil) will many times cause a person to undercharge a system. It also causes extremely inefficient cooling capacities because the coil cannot pick up the heat in your house. Your coil is more likely to freeze over, then you get no airflow at all. Use high quality filters, and check the coil itself for any obstructions once a year. In a new system (if you decide to go thqt way)have the coil installed in such a manner that you can gain acess to it easily to do your yearly check. Discuss that with the installer.
In most areas natural gas is cheaper to heat with. In my area electricity is almost twice as expensive to use than gas. Contact someone who is using gas, quiz them a little about why they are using gas. If gas is cheaper, you may want to consider other gas appliances such as dryer, water heater, stove. I like nat. gas, but I would use electricity if it were cheaper. Hope this helps
 
  #6  
Old 07-16-01, 07:28 AM
Goodwrench
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Thanks ifix4u. The $1000 est. was for purging the system, finding the leak, then fixing & refilling the system. Not even sure there was/is a leak. Think I will switch to gas. What do you think about the installers advice to put a 2 ton evaporater with 1.5 ton A/C unit? He said it would perform better. A 1.5 ton unit is plenty for the size of the house.
 
  #7  
Old 07-16-01, 08:57 AM
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Talking matching up?

Hi again,
Sounds to me as though your installer is not really sure what you need. I wholeheartedly disagree with mis-matching system components!! If that were the case then manufacturers would encourage the idea. They do not. If all you need is 1.5Ton, then have your installer put in a matched unit with an SEER of "10" or better. Make sure your installer has used the Manual J calculations to size the system properly. Don't put in the same size system just because that's what is there now. Newer systems are capable of being much more efficient than they were 20-30 years ago. If he is going by the old "rule of thumb", get another installer who uses the above type calculations, you will be much happier with the over-all performance of your heating and A/C system, because it will run more efficiently and cost you less money to operate. Hope this helps. CraigL..............
 
  #8  
Old 07-16-01, 11:25 AM
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Let's see

purge gas out,oops too much purge,add gas charge the customer again...1 grand to repair a leak,no way.Oh,yes the illegal purge of freon into the atmosphere.Listen to ifix4u.Call another company for an experienced "TECH".PDF
 
  #9  
Old 07-17-01, 04:43 AM
Goodwrench
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Smile

Thanks very much for your insight...
 
 

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