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Is it too cold outside to run my AC?

Hi All,

I’m new here and hope that you can help me with some questions.

I just had a Heil H4A836GKD / FVM4X4800A (3 ton) installed in my home at the very end of March. A couple of weeks ago it was fairly warm for April in New England and our inside house temp was about 75 degrees. Outside temp was about 63-65 degrees maybe slightly lower. Because my wife has bad allergies and I was anxious to try out our new AC I decided to turn it on. It came on for about 3 minutes and then it turned off for about 2 minutes and then it came back on for about 5 seconds. This cycle of off for about 2 minutes and on for 5 seconds continued. I had my AC on but my house was getting warmer.  I went on the internet and what I read made it sound like it was cycling and the it was best for me to turn it off and call the company who installed the unit. So I turned it off and called the installer on Monday (this all happened Friday evening. It was by no means an emergency so I waited until Monday to call).

We were told they could come out in a week and a half to test it – this was a little annoying considering we had paid good money for this and the first time we go to use it it did not work – but it is not the heat of the summer yet so I can be patient. They were supposed to come yesterday but they called and said it will be too cool for them to test because it is set up to not operate below a certain outside temperature (it was only about 60 degrees for a high yesterday maybe not even quite that high).

Here is where I am running into a wall. <strong><span style="color:#ff0000">They either would not or could not provide me with the temperature below which the unit will not operate. They then they proceeded to tell me the day I tried to run it the unit it was probably too cool outside and that is why it would not run properly.  Is 60* too cool for my AC to run?


<strong><span style="color:#ff0000">Can anybody provide me with the temperature at which my AC will not run because it is too cool outside?</span></strong> And <strong><span style="color:#ff0000">is it possible to lower this cut-off temperature if necessary?</span></strong> I ask because this could potentially be a problem for us because on sunny days our house can run 10 to 15 degrees hotter inside than outside and simply opening windows will not bring the inside temperature down to the outside temperature. Also as stated above my wife has bad allergies and one of the reasons we purchased the system was to try and keep the windows closed more to help ease her suffering. So it is conceivable that on a very sunny 70 degree day it could be 85 inside the house (that would be extreme but not beyond the realm of possibility). If we cannot run this AC at 65 degrees outside we could potentially have a system that does not fully meet our needs.

I have tried to find documentation for this system that would provide this information but have I have been unsuccessful.

<span style="font-size:12pt"> </span>

I called yesterday and asked to speak to the owner of the business because his assistant initially called to reschedule because it was going to be too cool yesterday. They wanted to reschedule for tomorrow which seemed silly because tomorrows high looks to be very similar to yesterday’s high temp. I can’t keep rearranging my work schedule so I can be at home only to have them continually reschedule because it is too cool out. I just wanted to know when and how this would be fixed.


During our conversation <strong><span style="color:#ff0000">he mentioned that the units are often shipped to them undercharged and that it may need to be charged. They were unable to determine if it was adequately charged at the time of installation due the low outside temperature</span> </strong>(again it was March). He stated that when we get a day “warm enough” (I’m still unclear what warm enough equates to in degrees Fahrenheit) they could come evaluate the system and <strong><span style="color:#ff0000">charge it if needed and this would most likely take care of the problem.

Does that sound reasonable?

</span></strong>I got the feeling he just wanted me off the phone and I don’t know if I should believe what he was telling me.

I want to believe him.  He came very highly recommended and on the day of the install everything went very well and his crew was very professional.

So at this point I am just trying to educate myself as much as I can because he seemed unwilling to help educate me with regard to exactly how the system should work and what my expectations should be.

I am still hopeful that it will all be taken care of fairly easily but I want to be as educated as I can just in case he is feeding me a line of BS.


Thanks in advance for your help.



  • Paul Fredricks_3
    Paul Fredricks_3 Member Posts: 1,549
    I think

    65° is the lowest. When you say it turns on then turns off, then turns on, are you talking about just the outdoor unit, or the whole system? I suppose if the charge is low or if it's cool out the outdoor unit could cycle on pressure, but the indoor fan should stay on the whole time. If the indoor fan is cycle on and off like that something else is going on.

    Of course, I don't know what system you have or how it's wired, just my 2 cents.

    I'd wait till it warmed up, like 70° to be safe. Then see what they find.
  • kentalope
    kentalope Member Posts: 4
    Just the outside unit

    Thanks for the reply. I am refering to the outside unit.  The inside fan runs continiously. We have it set to run all the time.  If we turn it off it turns off - no problem with the inside fan. 
  • icesailor
    icesailor Member Posts: 7,265
    "I" Think:

    I think that the installer is a maroon.

    If the installation has been paid for (and even if it isn't), the installer should have ran, not walked to the job to check it out. Even if it was too cool out. And I don't see that THAT was a problem. Just showing up and looking at the installation will make the customer feel like someone cares. Obviously, this installer doesn't care a lot because now that "I" know that the owner will post questions on The Wall, shows me that he knows just a little bit more than your average Ranger.

    The fact that the installer suggested that sometimes, the units aren't charged enough from the factory and may need more liquid, WTF? They always need more liquid. That's what the gauges are for. Was it even filled upon install?

    Because the owner couldn't be bothered he now has an upset customer. If the owner calls someone else and there is a problem, he won't be covered.

    The customer wouldn't be posting here if the owner had taken the time to go by and put in an appearance. A good customer relations practice.
  • don_9
    don_9 Member Posts: 395
    Charging ac

    Well to be fair to my hvac brother,personally I like to see more of a load when dailing in an ac unit.What I mean by load is higher outdoor and indoor ambient temps.

    The reason why one does not like to charge with low loads are the refrigerant does not have enough heat to boil off the liquid to a gas and the coil become flooded sending liquid back to the compressor that could damage the compressor over time.and the possibility of the unit freezing up.Also alot of time you will find that on the charging chart with low ambient temps that the manufacturer does not list what the superheat and sub-cool temps should be.

    The bottom line most unit now come with txv that maintain evaporator superheat and one could also weigh in the charge for the customer that has to have it now.

    Again I prefer to wait when there is a greater load place on the ac bc, I would like to see all the numbers with a wet coil verse a dry coil.I also like how much easier it is to dail one in with a load verses no load.
  • Empire_2
    Empire_2 Member Posts: 2,343
    edited May 2012
    50* and Above.

    I have no problems with it running or charging it.  Below that, it will need some kind of lo ambient control to keep head pressures up.  Even when checking at 50* or 55* the pressures across the board will be lower than desired, but the load should satisfy relatively quickly.  If you are trying to keep your house below 70* when cool outside, you will have problems.  Your HVAC guy should be able to help with the on off that you hear.

    Mike T.

    Hey Don, getting ready for the heat wave?
  • don_9
    don_9 Member Posts: 395
    you know it

    I have been ready for it.Always am this time of year.ask me again come august and i will have another opinion about out the sun block and lets get to work.Stay safe out there mike.
  • kentalope
    kentalope Member Posts: 4

    While I agree the installer could have handled the situation better I am also glad to hear there may be merit to his explanations. He also should have done a better job setting my expectations. In no way did he ever indicate that they may have to come back and charge the system on or before the day of the install. This only came about after I called saying it did not work. They showed me how to operate the thermostat and told me that if some rooms were too cold and some not cool enough to give them a call and they would come and re-balance the system. This certainly left me with the impression that when I turned it on it would work with out having to have them come out and add charge to the system.

    Also with regard to the thermostat, the person who explained it to me did not fully understand its capabilities - he explained it as a 5-2 thermostat. The box indicated it was 5-1-1 which was preferable because our Saturday and Sunday schedules are very different and we could befit from a 5-1-1. He stated that it was 5-2 and thought we would need a different thermostat for 5-1-1. He did not know why the box listed it as 5-2 or 5-1-1. Luckily the electrician left the box and the install guide (and not just the users guide which makes no mention of changing any of the settings via the service mode) which explained how to go into the service mode and program it to go into 5-1-1 mode. If I had not seen the box I would have never known it was capable of 5-1-1. It was not the electrician who explained the thermostat operation. He had already left. I'm sure he would have known how to change the mode from 5-2 to 5-1-1.

    Bottom line is I am relived that this will probably be resolved with a visit after it warms up. The owner needs to do a better job educating and setting expectations for his customers and do a better job educating his employees with regard to the operation of the equipment. I will provide him with that feedback in hopes that he will listen and do a better job going forward.

    I don't want to make it sound all bad - there were many positives with my experience but of course it is the negatives that the customer tends to remember. I just hope he will take may feedback and use it to improve customer relations. But I can also say that I will not be referring any of my friends to him for future business.

    Thanks to everybody here for your feedback. I has helped put me at ease. Much appreciated.
  • icesailor
    icesailor Member Posts: 7,265

    Which was MY point in responding. The installer may have done the nicest job in the world. But not being thorough is like leaving a mess behind. The customer will always think that you did a poor job.

    But be thorough in your explanations, and leave the area spotless, and explain everything you can to the customer and respond promptly, and they will think you are a hero. And recommend you to all their friends.

    Even if the job didn't come out as well as you liked.

    "A clean job is a happy job".

    I've gone to jobs where Sparky and the Wood Hackers had piles of crap up to my ankles, in the area where I needed to work. I've spent a day cleaning up my areas before I even start. I don't want to step on a nail, or twist my ankle. Then, when Sparky and the Wood Peckers come into the area where I work, I tell them to be sure to clean up after themselves. If they tell me that they will clean up when they are done in a few days, I tell them that I will be cleaning up after them and dumping all their $hip where they are working and in front of where their panel is. I don't usually have to do that.

    My old late boss DEMANDED we clean up at the end of EVERY DAY and every truck had a corn broom and a dust pan and brush. No exceptions.
  • Techman
    Techman Member Posts: 2,144
    edited May 2012
    Residential AC

    A simple explination @ the end of the install would have elimated this minor problem ,that being, we MAY have to come back in warmer weather to start and check the operation of the system.Now, that being said, the regular/normal/typical home AC is NOT designed/installed to operate when O.D. temps are lower than 65-70*. But they can be ,if proper "low ambient" controls are added.Commercial application's of your unit have them installed so their AC can run properly in any ambient temp.Most mfg's of residential AC  put in only enough freon for "about" 25' of copper tubing. Longer distances need more freon to be added.Your system is a 13SEER and most 13SEER unit's do not have a "low pressure safety" control that is factory installed,but, something is causing your unit to short cycle, so maybe Heil does have that safety control. I will check that out.                                                                            

          Now, as to your wifes allergies.What was put into the AC system to relieve her discomfort? A super good air filtration device or a UV light ? The normal 1" air filter's do a lousy job of cleaning the air of allergins. Keep us upto date on your situation. Now, if there was no converastion about you needing to run the AC when the indoor temp's get warm then I would give the AC guy some slack.But,when you called for service I think someone should have responded ,IF ,you said "We need our AC on due to my wifes allergies " .Then the AC Co.should have told you about the extra/chargeable controls , AND then  sent a tech out to solve the situation. We have a couple of customers a year that want what you want.NO PROBLEM!
  • kentalope
    kentalope Member Posts: 4
    TX Valve

    So it finally got warm enough for the installing company to come out and check out my system.  It seems it is a faulty TX valve.  It has to be ordered.  It should be here next week.

    It makes me feel a little better with regard to the owner basically telling me to clam down because it was most likely just too cool outside - WRONG it was (is) broken.  Don't treat me like a child just fix it.

    I'll let you all know when it is finally fixed.
  • Brp814
    Brp814 Member Posts: 22
    5-1-1 thermostat

    Do you have a Honeywell 6000 thermostat? If you do, it can be changed to a 5-1-1 program. The 6000 thermostats come set from the factory in a 5-2 mode. It is up to the installer to change the settings in the Installer mode. The installation instructions tell you how to access this. Very easy to do. Once you are in, you can change systems, like cool only, etc. The one you want to scroll to is 16. 0 is a 5-2 mode, 1 is the 5-1-1 mode. Again the installation instructions explain all of this. Hope this helps.
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