HVAC

Have HVAC questions? Ask an HVAC Expert for answers

Ask an Expert,
Get an Answer ASAP!

I have a Ruud Furnance/Heat Pump system. Heat Pump is

Customer Question
UPLA-031JAZ. Air Handler is UBHA-17J11NFAA...
I have a Ruud Furnance/Heat Pump system. Heat Pump is UPLA-031JAZ. Air Handler is UBHA-17J11NFAA. Original thermostat is Rheem part number 41-20804-15. The thermostat will consistently read 5-10 degrees warmer than the air in the house really is. I even installed an Ecobee and a Honeywell Lyric T5 with the same results. The air temp is 5-10 degrees cooler than the stat will read. When I put my hand on the stat it's warm. When I take the stat off the wall the wires and wiring cradle are warm. What causes this heat and how can I eliminate it?
Submitted: 1 month ago.Category: HVAC
Show More
Show Less
Ask Your Own HVAC Question
Answered in 4 minutes by:
3/20/2018
HVAC Technician: airheatman, HVAC Technician replied 1 month ago
airheatman
airheatman, HVAC Technician
Category: HVAC
Satisfied Customers: 8,977
Experience: Furnace, A/C and heat pump specialist.
Verified

If the stat is reading higher than room temp there has to be something generating the heat.It can be coming from attic air down wall .Remove thermostat and stci a thermometer in the whole in wall and see if the air is hotter than room temp.If so, use foam insulation to seal whole in wall where wires come through.

Make sure there is no light or heat source near thermostat also.I had one once that installer mounted too close to a wall scone and was giving it a false reading.

Ask Your Own HVAC Question
Customer reply replied 1 month ago
I took my Fluke with a temperature probe wire and stuck it through the drywall into the cavity. It reads 1 degree F cooler than the hallway. There are no lights, switches, appliances or anything like that on or near or around it. Behind this wall is a staircase to the upstairs.
HVAC Technician: airheatman, HVAC Technician replied 1 month ago

When you say,the thermostat is reading warmer than room temp in the house, are you taking the room temp right beside the thermostat with the Fluke?

Ask Your Own HVAC Question
Customer reply replied 1 month ago
I have a thermometer in the main part of the main floor. It reads 64 degrees. I move it to the hall and it reads 64 degrees. I take the fluke and the thermometer attachment and it reads 64 degrees in the main part of the house and the hallway. I stick the attachment (which is a high temperature thermometer wire probe) through the hole where the wires come out of the wall and it reads 63 degrees. But, the thermostat (Rheem, Ecobee and Honeywell Lyric T5) all read between 72 and 75 depending on the device. I take the device off the wall and let things cool off. When I put them back on the wall and hook things up again, the temperature on the device reads correctly. After being connected for a few minutes, the temperature spikes.
HVAC Technician: airheatman, HVAC Technician replied 1 month ago

Sounds very strange.Three different thermostats all read high but the fluke reads correctly in hallway. ONly thing I could imagine is something to do with the load through the thermostat control wires. Touch the Fluke probe against the wires and see if it also climbs

Ask Your Own HVAC Question
Customer reply replied 1 month ago
The wires read about three degrees above room temperature right after I take the stat off the wall. They read ambient temp when things have cooled off. There's no difference in temp across the different wires.
HVAC Technician: airheatman, HVAC Technician replied 1 month ago

If you have an amp meter clamp around wires while thermostat is connected but everything off and see if there is any load on the wires.

Ask Your Own HVAC Question
Customer reply replied 1 month ago
I'll have to get a clamp accessory for that test. I'll get one later tonight.
HVAC Technician: airheatman, HVAC Technician replied 1 month ago

Not thinking of any reason for those wires to be warm unless there is a load on them

Ask Your Own HVAC Question
Customer reply replied 1 month ago
Okay. I'll let you know what I find out. So many things miswired on this system. Thanks for your patience as we get it sorted out. I replaced the main breaker cuz it quit holding itself closed. And the slot next to it was melted from another breaker failure. It looks like this system has had issues for a while.
HVAC Technician: airheatman, HVAC Technician replied 1 month ago

Just a thought.Is the thermostat wire 18 gauge (not thin phone wire)?

Ask Your Own HVAC Question
Customer reply replied 1 month ago
It's proper 18 gauge thermostat wire. That's one of the first things I checked when we were trying to determine which wire went to the heat pump vs the stat.
HVAC Technician: airheatman, HVAC Technician replied 1 month ago

Sure would like to know what we determine in the end.

Ask Your Own HVAC Question
Customer reply replied 1 month ago
Okay. I've taken an AC voltage detector and checked each wire at the stat for voltage higher than 24. None of them are carrying anything higher than 24 volts.
Customer reply replied 1 month ago
I think I found the problem. The heat strips will occasionally run without the blower turning on. The heat will then come up the return air duct and exit right under the thermostat.
HVAC Technician: airheatman, HVAC Technician replied 30 days ago

Let,sget that issue corrected(replace sequencer or whatever is causing strips without blower) and see if issue goes away.That one definitely sounds far fetched.

Ask Your Own HVAC Question
Was this answer helpful?
Ask airheatman Your Own Question
airheatman
airheatman
airheatman, HVAC Technician
Category: HVAC
Satisfied Customers: 8,977
8,977 Satisfied Customers
Experience: Furnace, A/C and heat pump specialist.

airheatman 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

6,938 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

Kenton Guidry

Kenton Guidry

HVAC Technician

963 satisfied customers

12 years install/service experience.

Brian HVAC Guy

Brian HVAC Guy

HVAC Technician

953 satisfied customers

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

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
Rental hot water tank - serviced and insulated pipes Oct
rental hot water tank - serviced and insulated pipes Oct 2017 by Reliance tech-ice build up at elbows on insulated outside plastic pipe - when fan comes on -can hear running water outside from inside … read more
Rick the plumber
Rick the plumber
Owner
9,857 satisfied customers
I have a line volt thermostat controlling 1/2 of a 120 v.
I have a line volt thermostat controlling 1/2 of a 120 v. outlet that runs a pump on my heating system. What do I need to change it to a low volt stat for more accurate control and possible setback op… read more
Rick the plumber
Rick the plumber
Owner
9,857 satisfied customers
I'm tried to install a new Eecho 4 thermostat controller and
Hi. I'm tried to install a new Eecho 4 thermostat controller and now I have no power coming from the furnace. I think it should be 24V. … read more
Billy
Billy
Journeyman Service Technician
State Licensed Mechanical Contractor
9,330 satisfied customers
My carrier thermostat control 's display just went blank. I
My carrier thermostat control 's display just went blank … read more
HVAC Guru
HVAC Guru
Service Technician
Associate Degree
682 satisfied customers
Question about basement insulation... It's not a problem -
It's not a problem - it's a question...we live in the Atlanta area. 3 years ago, we purchased an existing home that has a full, unfinished walk-out basement, which means that the entire north and west side of the basement is above grade. The south and east walls are poured concrete and are below grade. When we bought the home, it had zero insulation in the stud walls on the north and west sides. The concrete walls also were not insulated. However, there was faced fiberglass insulation stuffed between the floor joists in the basement ceiliing … read more
Rick the plumber
Rick the plumber
Owner
9,857 satisfied customers
Gas boiler thermostat controles circulating pump hot water
gas boiler thermostat controles circulating pump hot water remains hot and is distributed by convection, how correct … read more
Rick the plumber
Rick the plumber
Owner
9,857 satisfied customers
The yellow wire on the blower motor through insulation. It
The yellow wire on the blower motor burnt through insulation. It appears to be 15 years old. Would it be safe to repair the yellow wire and continue to run the motor? The ground wite is hanging loose … read more
Billy
Billy
Journeyman Service Technician
State Licensed Mechanical Contractor
9,330 satisfied customers
I have a -Rodgers model 1F97-371 thermostat controller. How
I have a White -Rodgers model 1F97-371 thermostat controller. How do I get it out of the lock mode?… read more
Rick Mather
Rick Mather
HVAC Technician
Vocational, Technical or Trade Scho
3,133 satisfied customers
Is there a zigbee thermostat controller for a gree ptac? I'm
is there a zigbee thermostat controller for a gree ptac? … read more
gotoman for ac
gotoman for ac
HVAC Service manager and owner
Associate Degree
4,135 satisfied customers
Where is the fuse in my hvac unit. The thermostat control
Yes. The thermostat control shorted out. I suspect a blown fuse.… read more
Rick the plumber
Rick the plumber
Owner
9,857 satisfied customers
I'm looking for the best method and type of insulation to
I'm looking for the best method and type of insulation to use in an 1890's home that has non-uniform stud and rafter spacing that ranges from 28"- 34" on center. In this process should I use a vapor b… read more
Rick the plumber
Rick the plumber
Owner
9,857 satisfied customers
I need to replace a Zone Perfect Plus thermostat controlling
Hi, I need to replace a Bryant Zone Perfect Plus thermostat controlling two zones. My contractor is quoting $1300 plus to replace it and says there are no cheaper alternatives. Is there any simpler af… read more
Phil
Phil
Mechanical Engineer
Degree, Mech Engr Technology
6,938 satisfied customers
What is the use of insulating suction pipe of compressor? I
What is the use of insulating suction pipe of compressor ? I mean is it useful in package units also ?… read more
Brian HVAC Guy
Brian HVAC Guy
HVAC Technician
High School
953 satisfied customers
I purchased a 60 x 100 insulated metal building. It had 3
I purchased a 60 x 100 insulated metal building. It had 3 1991 7.5 ton gas packs in it using lp tanks. The tanks are gone and they stole the guts out of the 1991 units. I'm building living quarters on… read more
Phil
Phil
Mechanical Engineer
Degree, Mech Engr Technology
6,938 satisfied customers
What is the best attic exsaust fan thermostat controlled for
What is the best attic exsaust fan thermostat controlled for an 1800 sf house? … read more
Phil
Phil
Mechanical Engineer
Degree, Mech Engr Technology
6,938 satisfied customers
Instaling fie insulation. Which way does the metal piece go
which way does the metal piece go to hold the baffles … read more
Phil
Phil
Mechanical Engineer
Degree, Mech Engr Technology
6,938 satisfied customers
Dose the ac unit outsde need a foan insulation, yhermostat
yhermostat turns unit on the unit outside blow cold air … read more
Phil
Phil
Mechanical Engineer
Degree, Mech Engr Technology
6,938 satisfied customers
My honeywell thermostat control panel displays only 5 empty
My honeywell thermostat control panel displays only 5 empty boxes on the bottom of the display screen … read more
airheatman
airheatman
HVAC Technician
8,977 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