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Electrical Wiring in the Home/A/C broken thermostat caused high electric bill+ leakage


Thermostats ( old and  new replaced)
Thermostats ( old and  

leaking ceilings
leaking ceilings  
Dear Will Babbitt,

1 year ago I moved to a new apartment and my first electric bill that I received exceeded my norma 9 times ($362 for 60 days, 1800kw/H for this period).For the thrid billing period when A/C was fixed  my bill came ($45 and 180kW/h for 2 month cycle). From beginning of our relocation the ceiling under the centralized A/C unit started to leak. Even I notified the complex manager about the problem, she ignored my complaint and did not come to check what is wrong with A/C. It was September and we did not switch on the A/C at all. The only electrical device in our apartment was our middle size fridge and laptop computer.

After I got that huge first bill, I became very concerned about the causes of high amount. By that time the ceiling started to leak heavily, and there were mold problems. Finally, after visiting the City municipality and requiring the inspector, the manager arranged to fix the A/C. Visiting A/C technician found that A/C coil was full of ice  during  these 2 months. THEY CHANGED the old Honeywell t/stat to a new one with digital display .

After 6 months they fixed  A/C, when my electrical bill became  a regular ($45 for 2 months), I wrote an official demand letter to the complex owner asking  to reimburse me electrical costs caused by faulty A/C. They refused to reimburse  mentioning that THE  HIGH BILL CAUSED not because A/C thermostat was broken, but because I did not fully turned off the thermostat and it continued to work all that time (it's not true), so he puts all problems on my shoulder. Besides, after replacing the old thermostat with a new one, my electrical usage became to normal. I believe, that if their A/C thermostat would be in proper working  condition where should not be any leakage, mold, and A/C thermostat would not be replaced as soon as I  complained to City Authorities. I have a small claim court soon and would like to know the opinion  of the A/C expert about that the OWNER wrote me in regards to my Demand letter refusing to reimburse me  A/C caused electrical costs.

Your opinion on explaining of the situation is highly appreciated.
Thank you very much!

Please have a look to the pictures attached."

Ann,  believe me I feel your pain.  My house caught fire from of all things, a bad coffee maker cord back in February,     and we just got moved back in home with all kinds of insurance and builder problems,   going on and on and on,

But your problem is just as much of a mess,   and a hard one to prove,   but I would suggest as opposed to your letter to me,   when you prepare for court, you put the problem in outline form, keep it simple,  try and keep the dates out beside the events,   when you contacted the owner, so on.

You like me,  try and put every thought and event we can into the written explanation and most people,  I don't care who they are, are busy and just prefer a simple format they can read fairly quickly,  plus most are not technically oriented,  so all that has to be put in layman's terms as best you can.

Your best bet is to get a look at the old thermostat,   now they probably destroyed it, but maybe it is still around,    if they use it as evidence,  your defense is they replaced it,  so they KNEW it was bad or else  why replace a functioning thermostat?

Second if you can get your hands on it,  [if they use it for defense, you get access for your side of the story]  and get it evaluated.

Their defense that you DID NOT FULLY TURN OFF THE AC,  is just not a possible contributing factor.  If you want to run AC   24/7  it should run  24/7  and even in the worst of conditions,  running the AC  does not in and of itself,  cause a specific problem.

If it is extremely hot, the AC can only drop he temperature  SO MUCH,   called the Delta T  a massive formula for determining the amount of temperature differential,     and to put in layman's terms,  if you have a properly installed and properly sized AC/Furnace unit,  and the temperature is  100 degrees,  the max drop may be somewhere around 15 degrees,   if it is 70 degrees the drop is the same PERCENTAGE,      

I say that for your information,   but the whole problem here,  assuming all you tell me is correct,   is the unit faulted,  be it the stat,  the wiring behind it,  and if you turned it on or off has NOTHING TO DO with frozen lines,      only if they told you     THE AC CANNOT BE RUN  IT IS BROKEN AND RUNNING IT WILL CAUSE SEVERE PROBLEMS,   and you ran it anyway,  OK  that could add to the problem,        BUT   

Why would someone who knew the AC was broken   put a sign or give you a warning,  when the absolute way to prevent more problems is to remove the fuses,  lock out the breakers,   there are a dozen ways to keep the AC off,  without depending on the tenant to not turn it on,   it makes no sense.

Their very statement that you did not FULLY turn off the AC,  [whatever that means]  is just some sort of diversion or shifting of blame.     Like I said if it was in proper working order,  you can run it all day and night.

So they KNEW it was low on refrigerant,  or had a leak, or some other problem and did nothing about it,  or they did no maintenance and had no idea it was faulted,  which means they did no maintenance.

It takes two small very small wires to turn on the Condensing unit,  [the unit outside that blows hot air out, usually the top of the unit]

These two wires are normally thermostat wires,  can and are often shorted, or touching turning on the outside unit,  and it would be transparent to you.

It sounds fairly simple to me:

You move in and it takes some time to get your first bill.

It is multiples of what you normally expect.

You have to allow time for an invoice to even notice in the first place.

Once you get your very high bill, you investigate.

Water is now leaking into your unit.

You complain, the thermostat is changed, and the high electrical goes away.

To any reasonable person there you have it.

I have no idea what your rental contract says,  some are written where the owner is not responsible for consequential damages from any faulted event,   I would read the contract or have a lawyer read it,     in reality,  it seems to me he owes you for the damages of high bills,   these are tricky, and you might look up one of our Lawyer experts for more information on that,     

But as far as you running the unit,  on purpose or by accident, running the unit IN AND OF ITSELF does not cause the unit to freeze,     only if the unit was the wrong size,  had low refrigerant,  clogged filters,  clogged air flow into the condensing unit,   or some other issue,   would running the unit cause more problems.

But I have actually found a frozen unit,  low on gas,  in an emergency,  let the lines thaw,  turn it back on and let it cool as best it can,  and running the blower by turning the unit on after allowing time for some thawing, actually helps melt the clog,   it is not a permanent fix, but it works in an emergency some times,  

NEXT  there should be provisions of the unit,  a drip pan or containing pan of some kind with a cleaned out drain hose,   because all refrigerant type units, have condensation as a normal part of operation,  it condenses the humidity in the air to water,  this water has to be drained away,     it also appears that not only was the unit defective causing the freezing,  plus a shorted control signal from a faulted thermostat,  or DO NOT FORGET   changing the thermostat could have by accident or on purpose cleared a short in the thermostat wires,  

So do not let them bring in the old thermostat and say they had it tested., and just because it was old,  it worked,      well,  that does not mean the wires behind it were bad,  or another short somewhere in the control circuit,        don't let them try the "this thermostat works,  we just put a new one in to be kind to our tenant"

And if the old thermostat proves to work,   how do you not fully turn off the AC?   That makes no sense,    it is on, or off,  by any control you have over it,    it matters not if you had it on or not,   it was frozen,  you cannot make it freeze,  UNLESS there was some kind of written warning not to turn it on,  but again  if they wanted the unit off,   you don't count on tenants to turn off their thermostats,  the owner locks out the unit so no matter what a tenant or anyone does, or what signal from a shorted wire or whatever goes to the unit,  it cannot come on,   a very good site to help you understand these issues   

It is not uncommon for the thermostat to be bad,   where say the cooling contacts stuck,  it looked like an older stat,   BUT often what also happens is the wiring behind the stat had shorted, intermittently or permanently  and by changing the stat,  the wiring problem is resolved,  sometimes it is not even noticed by novice installers.

As far as you turning the AC on or off,  there is no provision for you to partially turn it off,   it was either switched to AC and set to a temperature,    if it and the AC unit worked properly it would blow cold air.

If the lines were found frozen, and the cause of the leak,  there is nothing you could have done to cause that problem, even if you ran the AC,   how would you know the AC was frozen?

The most likely cause of a frozen AC blower unit,    is the "A" coil,  and not enough gas in the system to operate correctly,   this happens all the time.  Causes include, leaking joints, tiny punctures,  lack of maintenance,  [you might try and get a copy of the maintenance of the unit,  ie  when they changed the filters,  when they cleaned the condensing unit,  when they oiled the blower bearings, checked the belts,  typical stuff you do to an AC unit to keep it running in proper order]

They can no more prove you did not turn the AC off than you can prove you did,    EXCEPT  the OBVIOUS,    new thermostat,    much lower electric bills.

Now someone could say you used power on something else but it would have to be an amazing amount of small items, all the way to one HUGE electricity eating device of some kind,  which just does not seem probable.

I have done work for some of these rental homes and apartments, and most want everything patched or cheapened, anything but done  correctly.  Now I cannot say that about every owner,  some do what they should, but there are so many that do NO maintenance,   to save costs.

I understand they are trying to make ends meet,  but you HAVE to have some kind of maintenance program on a schedule for AC and HEAT.

Even a clogged furnace filter can cause issues where the blower driven air cannot blow across the cooled A COIL,   this can cause the condensing unit to freeze,     so asking for a copy or bringing up the question of how often and what was included in their maintenance is a valid point.

You have no way of know if there was a leak for years and years and how much mold is there, has been there, is still there.

I can tell you the last thing the owner wants to do is to turn in a claim to his insurance for mold,   it is as bad as a fire,     if he has insurance, or even a home owner,  when you turn in a claim for a fire,  or for mold,  most likely you will not be renewed,  most states will not allow canceling but they will non renew,  and trying to get insurance from anyone when you have a non renewal is a huge problem.

So you have some bargaining chips to keep that from happening.

You of course do not want to live with mold,   any and all mold must be removed,   and treated with the right kind of paint or other to seal the area and make sure it does not continue to grow,   hopefully it is not huge,  and the owner can get it done without a claim to insurance,  and done correctly  but I can promise you if he/she does turn it in,  it will bring on lots more problems.

I would hope that common sense would be a way for you and the owner to work out a deal without court,  but whatever you need to do   do it.

Research "frozen AC units" as a Google or whomever search,   and pluck out forums and technical documents that fit your situation as more evidence,   I would be happy to proof whatever you find,  and make sure it is in your favor,  as I only have one side of the story and believe what you say.

It is not going to do any good to say there are probably millions of rental units that are never given two minutes of maintenance,   but it is reality.

If the AC was on,   be it by switch or short,   and frozen,  you would notice nothing much of anything,  maybe some air would push by the frozen lines,  but it most likely would not be cold.

This is so typical and it is frustrating to me to hear it,  I see it happen all the time,   but I think you have a good case       other than what your rental agreement says,  it might say we do not pay for damages from broken whatevers,        most of the time those never hold up,  but it could be in there so be prepared by knowing what is in the contract and any kind of small print denying liability up front,         I think you can win,    even if there is such language,    but make sure you know   surprises are not what you want,        

I don't know the entire total value of all this,  if you have a bad relationship with the owner now,  maybe you need to be looking to move, and maybe you can strike a deal with the owner, where you go,  he reimburses you for X,   forgives any lease time,  and you part ways,  that gets you away from any mold issues,      you might want to buy a mold test kit,  remember you have send in a sample  so if you need it for court  you need to get going on it,     

Lastly do you have renter's insurance?  That might be an avenue, but let me warn you,  a claim can cause you more problems than just leaving them out of the picture and dealing with the owner,      but mold is going to cause him problems,   if he uses insurance,  that will be a problem down the road in all likelihood,    and costly to remove and contain,      and I would suggest you do the mold testing for your own peace of mind,    but if mold shows up in your living area,   then you have a whole new situation where a lawyer would probably take the case  if the owner has anything to go after,  

     something else to think about,       just be careful dealing with your insurance, if you have it and decide to go that way,   they would have to go after the owner if they cured your problem to recover their expenses,  but then you have a claim on your insurance history and that is not good,     so if you are going to investigate the renters insurance,   you might call and ask,   or read the policy,  but if you contact them,   I would ask for a " what if" scenario,          don't reveal you even have a problem until you get a feel for any issues for turning in a claim,     


If you need me quickly     my personal email is,   my shop is MEAR Services Inc,  in Kansas City Missouri,   phone is 816-650-4030,  email at MEAR Services is    name is plural   address is singular,       feel free to get back to me anytime,   and good luck,      I hate to hear these stories,  why people cannot own up to their own responsibilities,  I don't understand,  but we live in a changing world where half the country wants many things for free,   and have not a care how it works,  what it costs or what the ramifications are going to be down the line,     

No one is ever at fault,   especially in these rental things,  and again,   who puts out there    has Lawyers who will answer contract questions for you, deserves a ton of credit for their generosity in helping people by gathering and vetting experts,   and allowing the public a chance for help at no cost at all,   they are paying it forward and everyone who uses allexperts,  should at the very least   drop them a note of thanks,  it is not cheap,  or easy,  but they never ask for a thing,      

Keep me up on what is going on,     again    keep your court documents much less than I have here,         move in date,   first bill date,   past utility bills from another place showing you did not use AC there either would be very powerful,  what you did after the first bill,  first notice date to owner,   to city,   when the technician came,   what he said,  maybe you could get something in writing from him?,   and research inspectapedia and other sites for examples       why AC Freezes,        it will show you cannot freeze on from the thermostat,       without it being bad to begin with,    and then when the water showed up,   which shows the drain was inadequate or clogged too,     finally the blame of you not fully turning off the AC,  whatever that means,     

Running the blower by itself would do nothing,   there just is nothing you could do to cause this,  
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Will Babbitt


Electrical issues of all types, wiring, control, appliances, components, specialty in Electric MOTOR or APPARATUS trouble shooting, electric motors, electrical problems, single phase, three phase, DC, capacitors, elevator MG-Sets, modifications, reverse engineering, VFD Drives, single to three phase convertors. Repair of most any electrical/mechanical/electronic apparatus, OEM, AC, DC, Industrial Applications, Three phase, single phase failure mode, determining the root cause of the equipment failure BEFORE failure repeats, Antique appliances, electric motors, fans, ceiling fans, base mount fans, poor equipment performance, Modifications, habitual failures, vibration, redesign, obsolete issues, collectible items restored, rewinding. Owner of EMR Repair Inc More information on electric motors, under Engineering/Motors Ask about any electrical or mechanical problems in the home, office, or even at your work. B2B or business to business CONSULTING I can do but it would be a much more complex issue, that would require a significant amount of time. from there we can discuss and begin work on about anything. Industrial electric motors, controls, troubleshooting, vibration, alignment, any type of industrial or commercial electric/electrcical equipment For the home owner, renter, apartment if you have odd things going on, describe to me, photos are normally very helpful, appliances, heating and air conditioning issues, light switches, installation, DIY PROJECTS FOR THOSE NOT EDUCATED IN ELECTRICAL, we can do some things, but for safety and sanity reasons, I may refer you to a local electrician, and help you find one, help you with pricing and even speak directly with anyone you hire if you have issues,


Over thirty years with a major repair and sales company, VP of Operations, and former owner of my own specialty repair shops, MEAR Services local to Kansas City Missouri EMR Repair Inc., located in Kansas City Missouri, 2014 sold both businesses to JCI Industries, Lee's Summit Missouri Evaluation and repair of electrical/mechanical apparatus. Electrical and mechanical repairs, trouble shooting including, vibration and balance issues. provides this service, and the huge costs to provide help on about any subject. They provide the servers, the people to vet the experts, costs that would be the same as operating a good sized business, They should be appreciated for what they do, the huge costs and the great help they provide for free, Electric motor questions, can be answered here but there is a dedicated category that has other experts to help and add to a solution. Other common questions, are noises in the walls, breakers tripping, devices not starting or shutting down for no apparent reason, smoke alarms buzzing, thermostat change outs, or sizing wire or needing information for a new project, but anything can be resolved, anything, with enough effort and patience, DIY, with electrical is possible, but in most cases the use of a simple ohm meter or volt meter is needed, they can be purchased at any hardware store for a few bucks. If you have smoke, or smell smoke, don't be writing me, call 911 the Fire Department has no problem looking for smoke smells, better then spraying water on a blazing fire. DO NOT GET CAUGHT INVESTIGATING AND TRAPPED IN A BASEMENT LOOKING FOR A BLOWER FAILING< As to the tip jar, it is up to you, it is appreciated, every expert spends out of pocket that I know, we spend on IP time, computer wear, printing documents, books, and of course our time, but if we prevent a $400 service call, we did well,

Former IBEW, EASA, IEEE, UL, ..............


10 plus years, various Technical Schools, followed by Industrial College Credit and non Credit Courses, electronics courses, experience in most any electrical apparatus, electric motors and generators, AC OR DC, fractional to above 5000HP, other electrical apparatus, slip rings, sleeve [plain] bearings, lubrication, identification-no data plate, control components, service and sales. I have continued night schools for decades, the list is extensive. I have been in the business of repairing most anything with wires or mechanical parts for decades, I have some helpful hints and directions you won't have to dig up. Or hopefully not have to pay a huge service call invoice to find.

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