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A/c won't shut off unless we turn the system off - honeywell pc8900

A/c won't shut off unless we turn the system off - honeywell pc8900

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  #81  
Old 10-01-17, 01:54 PM
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AC running all the time/not cooling ..low Freon(R22) ~ 50 psi

I noticed recently that my AC was running all the time still unable to reach the set cooling point of 78 degrees. Sometimes it was not blowing as hard and air temp was not as cool. So I have it checked. I was told Freon (R22) is low and there must be a leak. Until tech does the leak test (extra cost to do it - N2 test) he would not be able to tell me where the leak is and it is even repairable or not. Since the system is 12+ years and the fact that I got old Freon, he is suggesting that I replace the unit with 410 Freon. He is also suggesting I can keep existing blower/furnace(gas) which normally lasts 20 yrs, and I can keep my control panel/T-stats. Is this true?
Can someone please suggest me what capacity I should be installing for a 2 story house, 2450 sq ft. Should I be replacing copper lines that connects condenser to coil and the thermostats. Currently my system is 3.5 ton, is this about right?
Thanks for any information.
 
  #82  
Old 10-01-17, 01:59 PM
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The unit can be leak tested with an electronic leak tester. Harder to find leaks require removal of refrigerant and the use of nitrogen.
Providing the lineset is correctly sized, not damaged and correctly brazed it can be reused.
Sizing must be done via manual J. Sizing just by square feet is wrong.
I would find the leak before I made a decision regarding repairing or replacing.
 
  #83  
Old 10-01-17, 02:02 PM
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Sometimes it was not blowing as hard
Sounds like a zoning issue. Not a refrigerant issue.

You could re-use the furnace. The condensor and inside coil get replaced.
 
  #84  
Old 10-01-17, 02:39 PM
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How expensive is this electronic leak test?
 
  #85  
Old 10-01-17, 05:57 PM
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You'd have to ask the company. Some do it as time and material, others do a flat rate. We do it as T&M.
Hopefully the tech carries the appropriate tool.
An electronic refrigerant detector is an expensive tool. Probably $400-$1,000 for a good one.
I carry 2 of these

https://www.amazon.com/Inficon-712-2.../dp/B00063VK6Y
 
  #86  
Old 03-17-18, 09:29 PM
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OK, I had a quote done today from a company and it is 20K plus for a 4 ton 2 zone system. Currently I have 3.5 ton system...please suggest. I was hoping somewhere around 8K. What brand do you guys recommend I currently have RHEEM.
 
  #87  
Old 03-17-18, 10:14 PM
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Was the leak ever found? Do you really need a new unit? Do you need 4 tons of cooling?
Read here for best brand information-

https://www.angieslist.com/articles/...vac-brands.htm
 
  #88  
Old 03-17-18, 10:20 PM
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Yes this company suggested me 4 ton. No, I have not done leak test yet. I was just looking around for different options.
 
  #89  
Old 03-18-18, 05:22 AM
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But how did they determine 4 tons was needed? Was a manual J/S/D run for your home?
Sizing isn’t done via opinion.
What duct modifications will be done to accommodate a larger unit?
I highly suggest finding the leak first. It may be a simple repair.
 
  #90  
Old 03-18-18, 09:57 PM
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I guess this company is just going by square footage...I would not probably have to change the capacity.ok can someone point me to to the right direction as to what website or resources I need to research to find a good honest company/person for the leak test/repair. I am in Cedar Park TX area. Also, there is a big duct coming out of plenum to return and this company was telling me it was a bad design, very old and causes issues.. Is that correct? I have two zone system.

Another question I have is if there is a slow leak would my system still cool but just work harder. I was thinking if there is a leak freon would all escape and I would have the cooling problem seen immediately...
 
  #91  
Old 03-19-18, 06:43 AM
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Sizing by square footage is incorrect.
Ask your friends and family who they can recommend.
Leaks can be very small or very large and everywhere in between. A leak doesn’t mean the unit works harder, it means it looses capacity due to insufficient charge to transfer heat. Running the unit with incorrect refrigerant charge can cause major damage that can include compressor failure.
 
  #92  
Old 03-20-18, 07:37 PM
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I had another technician come today. He used electronic leak detector and said that my ac is low on refrigerant and leak is at the coil which he said needs to be replaced. My condenser is 3.5 ton but coil is 4 ton., is this normal?
What do you guys suggest - should I be better off replacing the coil and condenser at this point keeping the blower?
 
  #93  
Old 03-20-18, 08:34 PM
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Differing sizes is normal. Nothing wrong there.
The evaporator is fairly simple to replace. How old is the system and what kind of shape is it in?
 
  #94  
Old 03-20-18, 09:32 PM
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Mfr date on compressor shows 2004. House was built the same year so I am assuming it is 13 or 14 years old.
 
  #95  
Old 03-20-18, 09:44 PM
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I’d likely start planning on new equipment with existing equipment that age.
 
  #96  
Old 03-26-18, 09:32 PM
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OK. so should I consider 1-stage or 2-stage, constant speed or variable speed? What SEER? There are simply too many parameters. I don't want to spend to much, just the bare minimum to keep the home cooling efficiently. Thanks for any suggestions.
 
  #97  
Old 03-26-18, 09:55 PM
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If you are on a budget..... you will stay with one stage and constant speed. Two stage units and variable speeds ups the price considerably but lowers the energy usage.

You should get several estimates from different companies now before the hot season. There are too many variables for us to pick a system for you.
 
  #98  
Old 04-05-18, 06:29 PM
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Got another quote today. Here are the options I was presented with...
14 SEER 3.5 ton
14.5 SEER 3.5 ton

15.5 SEER 2-stage compressor w/ variable speed blower 4 ton
17 SEER 2-stage compressor with variable speed indoor blower 4 ton


Which option do you guys recommend? Should I really need to consider 2-state variable speed blower?

1.
 
  #99  
Old 04-07-18, 10:56 PM
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Originally Posted by sghimire View Post
Got another quote today. Here are the options I was presented with...
14 SEER 3.5 ton
14.5 SEER 3.5 ton

15.5 SEER 2-stage compressor w/ variable speed blower 4 ton
17 SEER 2-stage compressor with variable speed indoor blower 4 ton


Which option do you guys recommend? Should I really need to consider 2-state variable speed blower?

1.
any suggestions/input please.
 
  #100  
Old 04-08-18, 03:38 PM
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Hi Houston204,
Here are the few pictures...sghimire's Library | Photobucket
How can I turn this on and off using the thermostat? I can manually turn it on using the knob shown on the picture though.
 
  #101  
Old 05-18-18, 03:41 PM
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Please help. I am replacing my HVAC coming next week...
 
  #102  
Old 05-18-18, 08:21 PM
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https://customer.honeywell.com/resou.../68-0171EF.pdf

I like figure 16...

Do you have the Prestige IAQ at this time or the 1st generation that we discussed way back when?
 
  #103  
Old 05-26-18, 12:04 PM
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HVAC system has been replaced last week with the existing zoning board and thermostats. Fresh air ventilator circuit is confusing me. I plan to now purchase new Prestige IAQ thermostat kit and connect it to the ventilator.
 
 

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