HVAC

Have HVAC questions? Ask an HVAC Expert for answers

Ask an Expert,
Get an Answer ASAP!

I have a 4 year old central heating/air unit (gas/electric)

Customer Question
Hi, I have a 4...
Hi, I have a 4 year old central heating/air unit (gas/electric) that's not working quite right. During the hottest part of the day and into the late evening (around 1 pm - 9 pm) the unit only works intermittently, but doesn't cool the house below 77 degrees (set at 72) and won't come on until it's 78 or warmer. Overnight and early day it works, but it constantly resets the clock. Power transformer in the attic shows 19.x vac while the thermostat shows 27.x vac.Changed the thermostat (from digitial programmable to digital programmable wifi capable) but it's doing the same thing all over again.One more oddity: late at night the thermostat display will essentially disappear, but then the unit begins working.A/C mfg: Amana, 3.5 ton
Submitted: 11 months ago.Category: HVAC
Show More
Show Less
Ask Your Own HVAC Question
Customer reply replied 11 months ago
Also, I had my brother in law, who completed HVAC school a couple of years ago, check the voltage transformer. It was 19.x next to the blower and 27.x volts at the thermostat
Answered in 1 hour by:
8/5/2017
HVAC Technician: Daniel Plourde, HVAC Technician replied 11 months ago
Daniel Plourde
Daniel Plourde, HVAC Technician
Category: HVAC
Satisfied Customers: 455
Experience: I've been in the HVAC buisness since 2008 working on residential, commercial, and industrial buildings
Verified

hi i am dan i can help you with this. one possibility is a safety switch is turning the unit off. the first one i would check is if it is in an attic there should be a large pan under the unit in this pan there is a water sensor that will turn off the unit if any water leaks into that pan. i would check to see if any water is in the pan during the times when the unit is not working.

Ask Your Own HVAC Question
Customer reply replied 11 months ago
No water in the pan. At all.
HVAC Technician: Phil, Mechanical Engineer replied 11 months ago
Phil
Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 7,426
Experience: Retired HVAC/ Electrical & Boiler contractor. Industrial
Verified

I see that you have requested a new professional, if that is correct, tell me if you think I will be able to help you or not.

------------

I am a retired mechanical engineer and HVAC/electrical/ refrigeration and boiler contractor... with 56 years in this business. The last 20 of those years consulting for major firms nationally..

.

All I ask is please select the***RATING LINK***at the top of your page, that is the only way I am credited through the site. Rating does not affect your charges nor ability to refund if not satisfied.

.

If you need to be coached through a full diagnosis/repair,and wiring etc. for up to two days, and wish to be trained to use test instruments...... that goes well beyond' Just a simple Answer' of course, and goes beyond what most other experts here offer.....rate my simple answer so far positively.. and I will deliver that training and coaching to you All on the same dime so to speak.

.

Attach a close up photo of the wiring diagram glued to the inside of the blower access door and I will mark it up with troubleshooting instructions then follow up with step by step training and coaching until you have a solution.

.

Photo must be exceedingly well focused. Use the 'add files' link next to your send button to get the photo to me.

.

Phone call offers:

If you wish to accept the companies $25 phone call offer,if indeed they send you one, this will go a *lot faster, but it IS 100% optional... or we can continue here in this dialog box at no additional charge.

---------------

Regarding the issue with your amana unit. Here is a list of things that will cause the problem, we can address each one id detail if you choose to continue with me:

1. Older unit that has not had its condenser coil cleaned in some time.

2. A service person has recently worked on it and added refrigerant that it did not need so now it is

over charged with refrigerant

3. As the previous expert suggested, there may a float switch in the condensate line shutting the system off

as the condensate drains too slowly, that would be the hidden drain pan, inside the box with the cooling coil in it, not the back up safety drain pan visible under the entire unit which normally runs dry

4. Unit is newer, and is undersized for the home,

5. If the system worked well before you changed the thermostat, you may have made a wiring mistake, or

programmed the thermostat for the wrong type of system. or with too great a differential,

Let me know on each of those points, we can go from there

Ask Your Own HVAC Question
Was this answer helpful?

How JustAnswer works

step-image
Describe your issueThe assistant will guide you
step-image
Chat 1:1 with a hvac technicianLicensed Experts are available 24/7
step-image
100% satisfaction guaranteeGet all the answers you need
Ask Phil Your Own Question
Phil
Phil
Phil, Mechanical Engineer
Category: HVAC
Satisfied Customers: 7,426
7,426 Satisfied Customers
Experience: Retired HVAC/ Electrical & Boiler contractor. Industrial

Phil is online now

A new question is answered every 9 seconds

How JustAnswer works:

  • Ask an ExpertExperts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional AnswerVia email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction GuaranteeRate the answer you receive.

JustAnswer in the News:

Ask-a-doc Web sites: If you've got a quick question, you can try to get an answer from sites that say they have various specialists on hand to give quick answers... Justanswer.com.
JustAnswer.com...has seen a spike since October in legal questions from readers about layoffs, unemployment and severance.
Web sites like justanswer.com/legal
...leave nothing to chance.
Traffic on JustAnswer rose 14 percent...and had nearly 400,000 page views in 30 days...inquiries related to stress, high blood pressure, drinking and heart pain jumped 33 percent.
Tory Johnson, GMA Workplace Contributor, discusses work-from-home jobs, such as JustAnswer in which verified Experts answer people’s questions.
I will tell you that...the things you have to go through to be an Expert are quite rigorous.

What Customers are Saying:

You did one super job of explaining to me everything there is to know about this fridge. I'm looking forward to asking you questions in the future.

JimmyBagley, IA

Wonderful service, prompt, efficient, and accurate. Couldn't have asked for more. I cannot thank you enough for your help.

Mary C.Freshfield, Liverpool, UK

This expert is wonderful. They truly know what they are talking about, and they actually care about you. They really helped put my nerves at ease. Thank you so much!!!!

AlexLos Angeles, CA

Thank you for all your help. It is nice to know that this service is here for people like myself, who need answers fast and are not sure who to consult.

GPHesperia, CA

I couldn't be more satisfied! This is the site I will always come to when I need a second opinion.

JustinKernersville, NC

Just let me say that this encounter has been entirely professional and most helpful. I liked that I could ask additional questions and get answered in a very short turn around.

EstherWoodstock, NY

Thank you so much for taking your time and knowledge to support my concerns. Not only did you answer my questions, you even took it a step further with replying with more pertinent information I needed to know.

RobinElkton, Maryland

< Previous | Next >

Meet the Experts:

Phil

Phil

Mechanical Engineer

7,426 satisfied customers

Retired HVAC/ Electrical & Boiler contractor. Industrial

Rick Mather

Rick Mather

HVAC Technician

3,133 satisfied customers

35 years experience, HVAC

Matthew

Matthew

HVAC Technician

2,014 satisfied customers

14 years experience in the HVAC field of service, installation, Manual J & D calculations

Brian HVAC Guy

Brian HVAC Guy

HVAC Technician

1,019 satisfied customers

I have been an HVAC/R mechanic/technician for 30+ years.

Kenton Guidry

Kenton Guidry

HVAC Technician

963 satisfied customers

12 years install/service experience.

Rick Ridley

Rick Ridley

UK Heating Engineer

871 satisfied customers

Retired But have had 30 years on the tools, Ex CORGI

Tom

Tom

HVAC Technician

770 satisfied customers

16+yrs HVAC/R service. Residential Commerical Industrial

< Previous | Next >

Related HVAC Questions
When I set my air conditioning at 68 degrees, the house temp
Hi. When I set my air conditioning at 68 degrees, the house temp will not drop below 72 degrees. I called to have a repairman come and they said it sounds like a thermostat issue. I have a Honeywell F… read more
Phil
Phil
Mechanical Engineer
Degree, Mech Engr Technology
7,426 satisfied customers
Rick, I am having issues with a similar question you already
Hi Rick, I am having issues with a similar question you already answered in reference to installing a wifi Honeywell thermostat. This model is RTH6580WF, connecting to a gas fired heating boiler with … read more
Rick the plumber
Rick the plumber
Owner
9,857 satisfied customers
I'm installing a Honeywell WiFi programmable thermostat on
I'm installing a Honeywell WiFi programmable thermostat on my system. It is anot older Goodman furnace and ac combo. I need to connect the "c" wire on the unit (using blue unused wire). … read more
Airheatman
Airheatman
Heating & Air Conditioning Contractor
6 years college
1,836 satisfied customers
York Diamond 80 furnaces with a Rodgers 50A50-241 board...
York Diamond 80 furnaces with a White Rodgers 50A50-241 board... That I'm fairly certain I just fried. Was trying to move from 2 wire thermostat control of the unit to, well, more; so that I could con… read more
Airheatman
Airheatman
Heating & Air Conditioning Contractor
6 years college
1,836 satisfied customers
I have an American standard model number 2A6B3024A1000BA
I have an American standard model number 2A6B3024A1000BA Central Air Heat Pump. The outside unit will not start. Fan or compressor. Thermo inside when set to cooling clicks and the inside unit comes o… read more
Phil
Phil
Mechanical Engineer
Degree, Mech Engr Technology
7,426 satisfied customers
31 March 2016 08:30 about a week ago I thought the tstat
31 March 2016 08:30 about a week ago I thought the tstat went out (Radio Thermostat pictured) but I know it is a voltage/component issue. I did however buy a new tstat which is a honeywelll wifi tstat… read more
Daniel Plourde
Daniel Plourde
HVAC Technician
455 satisfied customers
Phil -- Your suggestion to look hole behind the thermostat
Phil -- This is Molly Frantz. Your suggestion to look for a hole behind the thermostat was spot on. Fire-retardant was put behind the thermostat and I though that solved the issue of the PECO thermost… read more
Phil
Phil
Mechanical Engineer
Degree, Mech Engr Technology
7,426 satisfied customers
Thermostat reads recovery mode, temp is 82, setting is 78.
Thermostat reads recovery mode, temp is 82, setting is 78. Air handler is 20 years old, we know that cause the fan motor was replaced last week. Condenser is 3 ton Goodman under warranty… read more
Tim H
Tim H
Lead building engineer
Vocational, Technical or Trade Scho
1,922 satisfied customers
I bought 2 Honeywell RTH221B thermostats to replace my old
I bought 2 Honeywell RTH221B thermostats to replace my old thermostats. I have a Rheem 2-unit (outside) and an aux unit in the attic. Problem is I can seem to get the wiring aligned correctly to cool … read more
Brian HVAC Guy
Brian HVAC Guy
HVAC Technician
High School
1,019 satisfied customers
HELP! Hunter 44273 thermostat killed my Trane Weathertron
HELP! Hunter 44273 thermostat killed my Trane Weathertron Executive series (age 27) heat pump. I called Hunter three times to get correct wiring and got three different answers. Recommended wiring was… read more
HVAC Guru
HVAC Guru
Service Technician
Associate Degree
682 satisfied customers
I need to install a new Thermostat to control a dependable
I need to install a new Thermostat to control a ' dependable Ninety Two' forced air heater (Gas). The instructions call for a 'C' wire to be added to the current 4 wires available at the moment.… read more
Phil
Phil
Mechanical Engineer
Degree, Mech Engr Technology
7,426 satisfied customers
Please help. I am installing a TH8320ZW1000. This ia a z-wave
Please help. I am installing a TH8320ZW1000. This ia a z-wave compatible thermostat. My HVAC is a Lennox HP25-311-1p. That is a Heat pump with Emer. heat. The wiring at the old thermostat terminals ar… read more
gotoman for ac
gotoman for ac
HVAC Service manager and owner
Associate Degree
4,135 satisfied customers
HelloHave lux programmer thermostrat 500a. Problem temp
Hello Have lux programmer thermostrat 500a. Problem temp set at 72 but shows area temp as high as 76-78. Did notice that while trying to make changes to time and temp it took several pushes of the nex… read more
Tim H
Tim H
Lead building engineer
Vocational, Technical or Trade Scho
1,922 satisfied customers
I have a Lennox G40UH(X) Series unit. For the past several
I have a Lennox G40UH(X) Series unit. For the past several days the A/C will only run between approx. 1 pm to 9 pm. After that it will not come on no matter what I do. The fan will not even come on wh… read more
Billy
Billy
Journeyman Service Technician
State Licensed Mechanical Contractor
9,330 satisfied customers
HI i have a cooling problem. we have the carrier ac, duct system.
HI i have a cooling problem. we have the carrier ac, duct system. we live in a hot country, in dubai, where the temperature outside in the evening is probably 35 degrees. in our main bedroom, i put th… read more
Mr. Jeff Pearson
Mr. Jeff Pearson
Refrigeration Systems
Associate Degree
145 satisfied customers
I have a 10 year 3.5 ton Rhreem A/C system on a 1,600sqft dwelling,
I have a 10 year 3.5 ton Rhreem A/C system on a 1,600sqft dwelling, with a 5 year compressor. A few days ago it stated during the day not to cool bellow 81 degrees and you can feel the heat inside the… read more
Paul
Paul
Vocational, Technical or Trade Scho
108 satisfied customers
Just purchased a Trane xl20 i 5 ton unit- We live in 2 story
Just purchased a Trane xl20 i 5 ton unit- We live in 2 story home 2200 sq ft with 18 foot ceilings downstairs. With AC set to 76 system turns on in late afternoon (outside temp 85) and house goes down… read more
HVAC_Doug
HVAC_Doug
Vocational, Technical or Trade Scho
I have a White Rodgers IF80 - 51 type thermostate. I had to
I have a White Rodgers IF80 - 51 type thermostate. I had to change the batteries, and in doing so the auto program running, because I corrected time on clock and day of week. the it started turning on… read more
freon
freon
Owner
High School or GED
214 satisfied customers
Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Disclaimer: Information in questions, answers, and other posts on this site ("Posts") comes from individual users, not JustAnswer; JustAnswer is not responsible for Posts. Posts are for general information, are not intended to substitute for informed professional advice (medical, legal, veterinary, financial, etc.), or to establish a professional-client relationship. The site and services are provided "as is" with no warranty or representations by JustAnswer regarding the qualifications of Experts. To see what credentials have been verified by a third-party service, please click on the "Verified" symbol in some Experts' profiles. JustAnswer is not intended or designed for EMERGENCY questions which should be directed immediately by telephone or in-person to qualified professionals.

Show MoreShow Less

Ask Your Question

x