Thermal imaging question; Radiant heating

(Robert Young) #1

Evening members.
Residential.
2001 build.
Geothermal heating. (Well)
Hydronic Radiant Floor. Garage. Basement.
Flooring medium. Concrete.
Suspect area. Is this a leak or are the heat signatures due to how the tubes are placed higher in the concetere?

Tubing material: PEX-AL-PEX tubing.
Manifold. KITIC manifold.
Class action suite till Jan 31 2020 if I am not mistaken.
Below is one of several thermogram images.
Camer Ti300.
Emissivity 92.
Suspect, tubing leak.
Cooler temps below the green and yellow blush.
Camera setting below.
Ops. Wrong image.
If you require ISO image send email.
Looking forward to replies.

h7.JPG

(Glen Gallo) #2

Do you have other photos? it would be nice to see how the rest of the floor looks,

was it just getting warmed up or at a steady state of operation? I would want an increase of normal operating temperature to increase the delta t if possible

I think I would lower the emissivity and see what that 95 seems a bit high for tile.

I would also play with background temperature

the idea is to see if it can sharpen the isotherm image

I like to switch palettes as well for the same reason some just look better than other and look more clear

I think a strip of electrical tape across the anomaly might be in order to make sure we are not reading a reflection on the tile of some sort.I don’t think that is the case but with an imager I always assume its lying to me and want to prove it is not. It is a quick and easy way prove it and I always have some with my imager

I would not call it a leak without proper information given that it is a tile floor perhaps a moisture reading on the grout areas near the anomaly. I would lean in that direction that it might be if the system was at steady state the spread seems odd for hydronic i would expect more consistency

I however being in a cooling climate rarely see those systems.

I look forward to what other think

(Robert Young) #3

Yes. Will post later.

Regular temp was ><66.2 when I arrived. I increased to 70F for 20 minutes to break thermal equilibrium.

Emissivity was adjusted at the site and in my office. Sitting at the residence, 92. Object. Glazed white ceramic floor tiles.
Sorry for the snipped image. It was from adjusting emissivity in the Fluke software. I wanted to get the best image possible so I ran through various settings and palettes.

I am just learning how to adjust isotherm image. The camera will be calibrated this week. My Ti100 9Hz comes back from calibration.
I purchased a Fluke 971 last week and had Primo Instruments do a NIST Calibration.

I ran thermograms through 13 palettes. That pic appeared to me to be the best pallet.

Good point about the tape. I had everything in my tool kit. I just forgot. It was a very technical inspection. The home had alot of equipment. I wanted to equal out my time on the home.

Good point. I should have used my Tramex MRHIII but the anomaly only became truly apparent when I returned home. To much reflectance in the basement. I could not turn off the lights. There was a small gathering of individuals and the developer in the basement.

4th geothermal this winter. I have been inspecting some very elaborate homes and investment properties.

Thanks. Hope this posts helped. Lets await more replies.

(Chuck Evans, CMI TREC 7657) #4

Changing emissivity will do nothing to improve the image for thermal pattern analysis. It’s only for temperature calculation, which is unnecessary here. Might as well leave it at 1.00.

If you want to increase the emissivity of a larger surface area to reduce reflection, electrical tape is not really practical. You can, however, spray the area of tile with Arrid Extra-Dry deodorant which will give you a more uniform emissivity of ~0.95 and the thin film will respond to temp changes more rapidly and will reduce reflections, giving you a cleaner image for pattern analysis. Don’t forget to clean up after.

(Robert Young) #5

Thank you, Chuck. Goods points.

Emissivity was adjusted, for the larger surface area, to reduce reflection, as prescribed.

What would cause the blush spread, as compared to the majority of tubing? Thoughts would be welcome.

(Chuck Evans, CMI TREC 7657) #6

Changing emissivity will not improve an image for thermal pattern analysis. it’s completely unnecessary.

(David A. Andersen, TN HI# 40) #7

It is nice that you guys are including as much information as possible, however your overthinking the process and getting off track.

Your thermal scan is inconclusive at this point.

As it appears you discovered this thermal exception after leaving the site and doing your report, it is what it is. It is now required that you go back and specifically address what you have found utilizing the proper techniques to analyze the situation that you suspect. The Preparation process for taking thermal imaging is more important than anything else in this application.

You have less than a 2° temperature differential in your scan and this must be increased. Also time is a factor. You need to shut down the system and let it stabilize to ambient conditions. Take a baseline scan which will indicate moisture during the cooling process of the floor. This is the same as doing a flat roof inspection. Temperatures remain for a longer period of time when water is involved versus normal conduction of the materials.

Then turn on the system and watch the thermal pattern and its rate of conductivity across the floor. If this is a water leak, the thermal pattern be more defined compared to what we are looking at in your scan right now.

Due to the density of these floors, conductive temperature rise will be slow and blurry regardless. This is where a real thermal camera is required.

Looking at what you have right now, I would be more inclined to call this a depth of piping/density changes in the flooring system than a fluid leak.

It is also recommended that you utilize isotherms to bring out temperature differentials that are smaller than the palette differential you are using. This pulls out temperature differentials of less than 1/10 of 1°C and provides a pattern of flow over time.

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(Glen Gallo) #8

I agree that the image itself does not change. After all that is set as is the focus.

But what we can see in the software does change when emissivity setting is manipulated.

I do not use my imager as thermometer. I do however in the software manipulate settings to provide different views or correct incorrect field settings

never heard of the arrid extra dry trick that sounds pretty cool. Thanks for that. Now if it came in black that would be truly awesome

(David A. Andersen, TN HI# 40) #9

That is only because it changes the range/span, which you can do otherwise with the slide of a mouse pointer.

Go back to your Focus, Range, Distance. These are the only things that cannot be changed or manipulated after you hit the shutter button.

Primarily “Focus” is your only concern in these applications.

This is a quantitative assessment and thermal tuning (range/span) and selection of palette (which have different temperature spans within the color scale) is your only concern.

(Glen Gallo) #10

Thanks David

what temperature difference should you see in the slab?

how long should it be turned off? And how long before the system would be considered warmed up?

That is only because it changes the range/span, which you can do otherwise with the slide of a mouse pointer.

I understand the first part but do not follow what you mean by mouse click

Agree with focus

My old camera had three ranges good unit old technology EZTherm with the ipaq just learning my current camera and the range settings are not quite the same I am just now getting used to it Ti32. really like the fusion bit and the picture in picture rocks got a deal on on ebay used nearly spent 9k on it when they first came out

(Chuck Evans, CMI TREC 7657) #11

All you need to do to tune for thermal pattern analysis is to adjust the span. You don’t need to mess with the emissivity setting unless you are doing quantitative analysis, just leave it a 1.00 and forget about it (that assumes you have proper Focus, Range and Distance). Use the span settings to thermally tune your image.

(Robert Young) #12

Chuck, during a thermal pattern analysis, auto span, level & range appear to be a caveat in my case. I am just starting to perform a more calculated thermal pattern analysis.

In this case I did not set distance, as well, I was not perpendicular the object, point of interest although for the past month I use manual Span/Level, and Set Foot Distance, include background Temp and RH%.
It will take time and education. A journey I am looking forward to continuing.

Thanks.

(Robert Young) #13

I started the analysis at thermal equilibrium. All objects were the same temperature. After >< 10 minutes I resumed taking qualitative measurements. I should have performed a qualitative assessment with my MRHII tramex moisture meter.

As for utilizing isotherms, I am just learning this technique. I purchased a Fluke 971 and had the instrument NIST calibrated. As well, I am picking up my spare ti100 that has been calibrated and bring in my Ti300 that will be celebrated this week.

Thank you Chuck and David.
Hopefully more inspectors will be discussing thermal imaging in the coming months.
Kindest regards.
Robert Young

(Chuck Evans, CMI TREC 7657) #14

The distance referred to in FoRD (Focus, Range, Distance) refers to the physical distance between the imager and the object being imaged when the image is captured, not the distance attribute in the camera setting. These three parameters are immutable once the image is captured so they must be right when you press the shutter button. Everything else can be adjusted/manipulated after the fact.

Emissivity, Distance, RH, RT parameters are strictly for calculating temperatures and can be ignored when performing qualitative analysis (they do not directly affect how the image appears for visual analysis).

Anything you do to increase the actual emissivity of your target (e.g., surface modification, shooting cavities, squaring to your target will benefit you by reducing the percentage of reflected radiation reaching your detector. This will affect how thermal patterns appear in the image.

(Robert Young) #15

Yes, that is my understand, although I was not aware of the acronym.

That is why I perform qualitative analysis. Unlike yourself, I have not achieved a level 3 to obtain analysis and remedy through thermography.

Yes, that is my understand. It will take me time to focus on a target to obtain a the best image, and your and David’s credentials.

Lets us remember. Most members here utilizing thermal imaging equipment during home inspections are not performing thermal inspections persay, but using thermal imaging equipment to detect anomalies that require further analysis with auxiliary equipment through verified application courses certifications, like myself.

Thank you all for the exchange but I am nowhere clearer on the question at hand.
Considering the entire radiant concrete, >1,400 sq.ft, these higher temperatures and patterns stood out. Based on all the information I provided, would you consider tubing failure or is there not enough information?

Kindest regards.
Robert Young

(David A. Andersen, TN HI# 40) #16

Fusion and PIP help to orient the scan (all those colors mean nothing to the reader). They are used for “What are we looking at here?”.

(David A. Andersen, TN HI# 40) #17

Also, you stated above about using your moister meter. Please realize that the same problems your having with thermal imaging is present with your moisture meter! A moisture meter is not any better than your thermal camera in most cases for determining water. As I see many Inspectors say they ‘verified’ with a moisture, you are not verifying. You are taking a second look from a different perspective.

Again, back to my above scan.

Cold air meeting humid indoor air in a kitchen produced moisture readings in the ceiling against the wall. When your there to find a water leak from the outdoors and what you found is not a water leak from outdoors, your wrong! And that cost! Your sending someone looking for a leak that does not exist. So, do we recommend stopping the air leak with added insulation? Not in this case. Further testing found that HVAC air duct leakage to the exterior caused a significant depressurization if the interior of the house. This is the cause of air infiltration. The recommended repair is on the HVAC unit, not the wall insulation. You will not have any infiltration if the indoor pressure is equal to or greater than the exterior, so there is no reason to play the insulation game.

(Glen Gallo) #18

David

Thank you for clarification.

The slab is something I will rarely see here but I am familiar with adjusting conditions. Being in San Diego where it is not uncommon for the home to be in thermal equilibrium with outside temperature I often have change the environment. The 10c delta that is easy to achieve elsewhere is not a slam dunk in my neck of the woods. I appreciate the answers on something I might come across once in a blue moon and now have a better understanding on how to image it and what to look for.

Agree with your comment on the picture in picture I do not think this camera gives me superior thermal images than my first camera but for someone that struggled to make reporting look good before This is a very nice upgrade. I used to tape a coin after warming it with my fingers on the wall when I found an anomaly in ir Image I would then then take a jpeg so the customer could clearly see location. I could not do this on some out of reach areas and would simply snap two pics place arrows for id. Now I am one click a voice note and go. I have more palettes as well, I don’t think it makes me a better Thermographer but I think it saves allot of time and give my customers a better report at the end of the day. Battery life is also better and the unit more ergonomic

Thank you and Chuck for your replies

(David A. Andersen, TN HI# 40) #19

How and when to take a scan is more critical than camera operation/settings.

I always run the camera even when things are not just right, because you never know what you may find and never be able to duplicate again.

But you have to have a plan based upon your initial observations.

The problem with HI, is you only are there one time. If you can not manipulate the conditions when your there, you may not be able draw a proper conclusion without a follow-up.

When you break out of the HI Standard, you must be willing to assume the Thermography Standards to continue the process.

(Glen Gallo) #20

David

I come from the building science energy audit side of things just getting my feet wet with HI

I can see many pitfalls from what I know as good imaging and conditions that will happen in HI

Daytime inspections ie thermal loading

not manipulating environment for best imaging

limited time allocated

I could go on

While this is limiting in many ways I can also see the benefit as an add on tools but would not consider in an HI quick scan to be a Thermal Imaging Report

Analysis and and investigation is not part of the HI from what I can tell and I will have to remember that moving forward. From what I can tell it is a quick scan assessment recommend someone else when anomaly observed for HI

*edit after reading above I can see the issue is when to recommend and when not to based on the limit of the HI report That will take some experience moving forward

I have quite a few hours of camera time and owned one for 11 years. Always looking to expand my knowledge base. I appreciate you taking the time and sharing your knowledge