Ultra-fin plates

Kevin_in_Denver_2

How much do they want for those 1500 fins?

Shaun Anderson

Ultra-fin plates

What are the wallies take on Ultra-fin plates ? Homeowner seen it somewhere so he wants to add it his house addition. 215k btu's I came up with on my heat-calc. System consists of baseboard, in-slab, Ultra-fin and tie in an Indirect water heater. Current heat for house is baseboard with house addition going concrete in-slab and Ultra-fin for main level. Any insites would be helpful.

TheFuture

hr

I understand

they have a newer version that runs with the joist and doesn't require as much drilling?

I feel there is a place for this product. If you believe suspended tube can work under the right loads, UltraFin takes that one step further, by adding some "fin" to the bare tube.

I think Siggy may "model" this method for a future article.

Transfer plates are my first choice, but with low loads UF may be the ticket.

Start with a heat loss and get a real number regarding the BTU output you will need. Don't guess at this important first step. You will be rewarded with a quiet comfortable system if you plan ahead.

hot rod

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Shaun Anderson

I did

a heat-calc off their program and come up with 75,000 btu's on the add on. Homeowner wants to replace dying boiler from the 60's or 70's to a newer boiler and run just one. Existing house has baseboard that I added all up and times by 600 to get the btu's of the house. Added both up and derated for altitude/eff. and came up with 215,000 btu's. But I have never tried using the Ultra-fin product. Would have rather liked to run heat-transfer plates of the staple-up but homeowner is hooked on the Ultra-finned system.

Unknown

what's the Per Square Foot load on the radiant? If you're over 15 or so, I wouldn't waste time with the ultrafin.

Ron Schroeder_3

ultra fin also known as convective radiant

The opening page on their Web site declares: simple, effective radiant floor heating for quality homes (http://www.ultra-fin.com/). The heat emitter of the Ultra Fin system is a two piece pierced aluminum radiator that must be mechanically attached around 1/2" plastic tubing. High supply water temperatures (they claim independant testing and provide data for 150F and 180F) heat the aluminum fin which in turn heats up the air space within the joist bay. Convective air currents are recruited to warm the back of the subfloor and in turn heat the floor covering which then ultimately provides a fast response heating system to the home. This seems to be a forced air heating system without the air filter. I was asked by a homeowner to give an opinion on his self built installation. The ultra fin product was applied to P/A/P tubing. The home owner reported assembling about 1000 plate pairs each with four pop style rivets (4000 rivets), for the second floor of his work shop. The installer confirmed that installing this system below the subfloor while standing on a forklift 16 feet in the air was not simple at all. The literature wisely uses the adjective, effective, as this type of heating system is not nearly as efficient as it needs to be with current energy costs. I know of no other RFH system type who's supply water requires input temperatures that even come close to the ultra fin's requirements. Who on this board would deliberately design with high supply temperatures in a radiant application? The quick response time that the ultra fin system claims is also not necessarily an advantage. I have always found home owners to be more comfortable when I design systems that have slow temperature changes, not quick ones. I have also found long run time in boilers to be preferrable to short ones. Ultimately you have to discern your clients real wants but sell to their needs, and that without compromising what you know to be true and right. Cheers.

hr

A couple points

I don't know of any system that would be fun to install, or safe (OSHA approved) for that matter, from a forklift 16 feet in the air So I couldn't discount that against the product. Could you?

Lots of rivets, but then again 1000 feet of transfer plates takes lots of fasteners also.

As far as those high temperatures, plenty of hot water baseboards run in that range, and UF could be added to a system like that for floor heating quite easily. Probably for less than a mixing station and a low temperature radiant panel.

Certainly low temperature heating makes the most sense, but it is not always the ONLY way.

hot rod

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Jed_2

What about the air temp?

With straight boiler temps(160-180°F SWT), what could one expect sustained sub-floor temps to be? Materials exposure? I could see reset also, but with a C.I. conventional boiler, limited range. There is a distributor in my area pushing UF hard. But, I don't see it as a one size fits all system. Design software sets the tube spacing and #'s of fins. Maybe set a baseload, supplement as required? But, the sub-floor ambient is what I'm not comfortable with.

Jed

Shaun Anderson

Some of my rooms are over 15 btu per square foot. Masterbedroom = 28.2
Dining room = 19.9
Great room = 41.4
All the other rooms are within the 15btu per square ft.

So are you saying don't give a shot. This is my first Ultra-fin job. Like to see if it really works.
Thanks

TheFuture

Shaun Anderson

That is true, you really can't play with the tube spacing. On this job UF's program says I need 1500 10" fins to do this job. Total house is 3726 sq ft. for the add on. Using Kitec pipe for the jobs tubing for UF and in-slab. All I need to do now is tie-in the existing homes baseboard and add an indirect. Burnham 208 ng is whats going in.

Mike T., Swampeast MO

Given those output requirements with the affected spaces being the master BR, great room and dining room, and the general temperature requirement of ultra-fin, give HIGH consideration to panel radiators with TRVs for supplemental heat in the MBR and great room.

Am guessing that the great room has a lot of glass. Try to install the panel rads so that they "see" the glass, e.g. not beneath the windows. Size your panels to work with the temp required by the ultra-fin and for the difference between say 15/btu/sqft and the requirement. Multiple small panel rads will be preferable to one in a large space.

Master bedroom is another matter. Personally, I'd oversize the panel radiator, put it in view of the outside walls, integrate it into the aesthetic design, use less ultra fin and put the panel in series with the ultra fin. Why? The floor will become a "slave" to the panel. The floor will be tempered (e.g. not cold) with the TRVd panel providing comfort.

Dining room is the wildcard. If well open to the kitchen and typicaly unused except for entertaining the occupancy and appliance load will compensate for the calculated "lack of heat". In normal (unused) circumstance it should be a touch cooler thus reducing fuel consumption. If used daily, a TRVd panel rad sized to the difference (like the great room) will be good.

Andrew Hagen (ALH)

Ultra-Fin

Last I heard Ultra-Fin was recommended to be installed 30in on center perpendicular to the joists. Like Rob said, even if you run it at 180F it will provide minimal heating output. It's not going to be able to deliver the heat to the room at a high enough rate to prevent short cycling of the boiler. It's true that Ultra-Fin has more surface area than bare tube 8in on center on a square-foot basis (can you count both upper and lower sides?). However the fin is not in perfect contact with the tube. The fin is not backed by water, while the tube is. There's a lot more to it than there appears to be on the surface. I would really like to see some analytical reason why Ultra-Fin is designed the way it is.

It's like those magnets they say to clamp on your water lines instead of a water softener. It sounds too good to be true. It is. ....ignoring the placebo effect....

-Andrew

Unknown

Once you add in all those radiators, TRVs, and a seperate constant circulation circuit, you might as well just ditch the UltraFin and put in some real plates.

I would then hook up a length of baseboard (or panel radiators, depending on water temp requirements) in paralell off of a radiant manifold for the great room to supplement. If reset is used, its output will drop as the load drops, so it won't override the radiant. The radiant will be providing all heat and comfort except for a small portion coming from the supplemental emitter.

Alternatively, since most of your spaces are lower loads, you could really crank those water temps down and use some radiant wall in the great room to supplement (if invisible heat is a concern).

If you play with the water temps, you could do suspended tube in the very low load areas, and plates in the higher load areas. I would wager with a little figuring you could work out a one-temperature system by varying your installation methods for the load.

Mike T., Swampeast MO

Was thinking of cost and single-temperature system in that recommendation. Granted, panels and TRVs aren't the cheapest things in the world, but don't believe a separate constant circulation system would be required.

Ultra-fin seems to "live on the edge" with high temp requirement and relatively low delta-t. Such should pretty well guarantee long calls from the thermostat--even if the boiler is cycling on high limit during a call

With the TRVd panels (great room & possibly dining) in parallel with the associated zones (don't know if/how this is zoned however) and long heat calls, the panels would provide the necessary boost in colder weather and even help cut down on burner cycling during a heat call. Not the super-tight and fully modulating control of TRVd constant circulation, but with the ultra-fin providing a base load, it should be quite comfortable and offer significant control range (via the TRVs) for the room(s).

Series piping suggestion for the MBR might be a stretch. Was imagining this is a separate zone already with the panel installed in series after the floor loop and sized sufficient for heat loss of the space if it had full supply temp, e.g. not installed in series after the ultra-fin. Contrary to the first post, a TRV would NOT be required on this panel. Omitting the TRV would greatly reduce complexity.

Shaun Anderson

If it was you

would you try to run this in UF ? The homeowner is real fired up about using UF. So my contractor wants to give it a shot too. I'm just trying to get the insites from my wallie brothers. Everthing brought up in this thread makes me wonder. Is UF as good as the represent in this sitution ?

TheFuture

Mike T., Swampeast MO

No direct experience with ultra-fin. Am EXTREMELY skeptical of their output claims and HIGHLY SUSPICIOUS of their "independent" testing methods. The numbers do not appear to reflect even approximations of real-world conditions.

Customer rules however. Personally, I'd suggest that they speak with someone in their area with a somewhat similar home using ultra-fin.

Jed_2

Also, something to consider

I have run the UF sizing software, and for the life of me, I could not find any calculation, or report, which gave any floor temperature or unit load numbers, with any given panel construction. Kinda left me hanging with questions. Am I missing something with this software?

Jed

[Deleted User]

Conviction.....

In order to have convetive currents, there MUST be a difference in air temperture. No difference, no convection, possible conviction...:-)

There will always be the "radiant" component, but based on surface area, and surround temperatures, that too is limited.

I view this product as being a great means of providing floor conditioning, but am leary of being capable of carrying full loads at design condition.

Just another reason for the RPA to spend more of its members monies on research, development and a true output standard for all the methods available...

ME

Shaun Anderson

Plates are running $1.35 each. 10" plate with rivets.

Rick Kelly_3

Ultra Fin

This product is a boon to the fledgling heating contractor looking to compete against "true" radiant heating systems that feature energy efficient low supply water temps to achieve consistant comfort and fuel savings.

With UF installations requiring as little as 35% the tubing of a typical underfloor application coupled with the lack of supply temp modulation devices, quite a lot of the more precision equipment in a conventional radiant system is eliminated, leaving much room for contractor profit margins.

I don't rule out using any viable products available to me as I am committed to installing whatever is most appropriate to the job. I don't consider UF to be a radiant distribution system but an extensive expensive underfloor inefficient convective heating system.

ScottMP

Mark

I agree with you. For true convection there has to be a detla t fro transfer. How much ransfer happens in the joist once the bay is heated ? How much heat transfer really happens and again the high operating temperature dosn't make this a very viable option in my opinion.

Scott

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Andrew Hagen (ALH)

But

the RPA is there to promote all radiant panels. If they prove how poorly Ultra-Fin performs, won't they be damaging a member of the group they exist to promote?

Conduction is everything. Convection adds an unnecessary and incredibly inefficient link in the heat transfer chain. Response time is important. Fuel efficiency is important. Short cycling is important. Maintaining the room temperature reasonably near the thermostat setpoint is important. Maximum output is important. Ultra Fin addresses none of these.

There undoubtedly are homes out there with Ultra Fin that stay warm all year long. It may work, but the heating system could work much better.

-Andrew

Plumdog_2

regular fin tube

I've seen a couple or three attempts at joist bay heating with regular fin tube being employed. In one instance the floor was over an unvented crawlspace and insulation batts were installed under the fin tube. The batts became waterlogged from condensation, and half of them fell out from the wieght. The ply and joists were soaked thru and rotting with black moldy looking goo. This was a daycare center. Be careful.

Kevin_in_Denver_2

ultra fin Delta-T

"How much heat transfer happens once the the joist bay is heated?"

Well, it's an easy calculation if you start with a few reasonable assumptions. Everyone seems to think Ultra Fin makes a great joist bay heater. OK, so the air in the bay gets pretty hot, lets say it equals the boiler setpoint temp. of 160*

Let's further assume tile on 3/4" plywood subfloor. The tile R value is negligible. Let's also ignore radiant heat transfer altogether for the time being.

The equation for heat flux is H=U*A*deltaT

deltaT= 160* - 70*= 90*F assuming 70* thermostat setpoint

U=1/(R1+R2+R3)

R1 and R3 are for the air films above and below the floor. .61 is an approximation for each of these. The subfloor R value is .94 for 3/4" of plywood. U= 0.46 btu/hr/ft2/*F

H= .46 x 90*F = 41.4 Btu/hr-ft2

Hmmm....that's a lot! It's also close to what the manufacturer promises at 160*, and would even handle that great room referenced above. Factor in perfectly uniform floor temperatures, 10-20% more heat transfer from radiation, and heck, maybe they've got something!

Upon further thought, you can convince yourself that the Ultra Fin mechanism minimizes the tile floor temps as compared to any other radiant floor method except suspended tube. The other methods have a certain amount of "heat striping" with localized hot spots.

Unknown

First, it's unlikely you'll get the joist bay to 160. Second, at that delta T you need to figure in back losses and edge losses which will undoubtably be present and significant, even if adjacent spaces are heated. third, if you are getting any kind of noticeable heat striping with other methods, the system is not designed properly. Fourth, if you did get the joist bay to 160, what exactly is that going to do to your joists and subfloor?

Finally, Ultra Fin is the only product out there that claims lower floor temperatures when you raise your water temperatures. That should tell you what to think of the "manufacturer's claims" there. http://forums.invision.net/Index.cfm?CFApp=2&Message_ID=172302#Message172274

George Peteya_2

Back to the Basics

1. Do a heat loss calculation. No guessing.

2. See Note 1.

3. Radiant really isn't about response time. If you want to change the room temp. quickly, that's why we have panel rads, fintube, and (!) forced air. That said, the limit to response isn't about fins, stamped plates, extruded plates, talon hooks, or pipe rail ... it's about the fact that there's an inch and a half of wood between the tubing and you. If you want response, consider radiant as first stage on o/d reset, and radiation as second stage, at high temperature.

4. We have all seen claims by manufacturers of radiant outputs of 40 or 50 Btuh/square foot. Yes, and your vehicle is probably capable of 120 mph or more, too. Neither is relevant to the world we live in. Radiant output is limited by floor surface temperature. Fire up your design software (I don't care whose) and see what floor temperatures are needed to produce 50 Btuh/sf at 70°F. room temperature. You'll get 90° or higher. IMHO, anything over 80° (maybe 82° in bathrooms) is too hot. So, whenever the heat load is greater than 20 Btuh/sf, you'll need supplemental heat, either second stage or concurrent, to keep the floor surface comfortable.

Andrew Hagen (ALH)

I agree

But I think we're talking about two different response times. I was talking about how quickly the surface of the floor responds to the fluid flowing within the tube. Having the floor surface responsive to the controls is important.

-Andrew

Unknown

You can't change a room temperature quickly. Only air temperature, and that's a big difference from a comfort standpoint! If you want to change room temperature as quickly as possible, conductive, low mass radiant is by far the fastest way to do it, since it heats the objects directly instead of just washing them in warm air. And there is a big difference there between convective (naked tube) and conductive (plates) joist applications in response times.

Requiring supplemental at 20 BTUs/sq ft is a tad extreme as well, IMHO. 85 degrees for max comfortable surface temperature is an industry standard and allows up to 30 BTUs/sq ft. I haven't heard of any complaints at that temperature. Though of course using OR to keep it at a minimum temperature is always, *always* a good idea. Not just for surface temperatures, but to keep the room.. not the air.. continuously at a comfortable mean radiant temperature.

Mike T., Swampeast MO

With ultra-fin (like any convection-based sub-floor system) you can't forget about what's happening inside the convection chamber (the joist cavity).

From a cold start (say the air in the joist cavity is 60°) you will get a whopper of heat output as the air rapidly heats and rises in the cavity. That air warms the surfaces of the cavity and cools. For a while you'll get fairly rapid convection (like the UF operational illustration).

However, as the surfaces of the cavity warm, the air temp difference inside the chamber will diminish and convection will slow. Why? Because there is less delta-t of the air inside the chamber thus less heat is able to be liberated from the UF.

While high initial output is certainly possible such is not sustained output. Sustained (not peak) output is what maintains the mean radiant temperature of the space.

Ken_8

WHOA !!!

You wrote, " Existing house has baseboard that I added all up and times by 600 to get the btu's of the house." ?

That is NOT the way to do a heat load. I can see the lawyers in the gates now...

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George Peteya_2

Radiant Floor Surface Temperature

Rob, I'm faxing you a chart that I picked up at an RPA seminar a few years ago. I think it's by ASHRAE. Let me know what you think ... either directly by email, or hang it up on the Wall! BTW, if you use a program such as Wirsbo Radiant Express, don't you get a warning if the floor temp comes out over 80°F.?

Unknown

I am not sure what to think. Apparently my clients like warmer floors. I would be especially interested in the testing methodology on that chart, since it would be *very* difficult to get objective results on something like that unless the people didn't know they were being tested, and you could somehow track their true feelings.

I don't use canned programs to do my design work, however AFAIK any warnings at 80 degrees are related to wood floor integrity in particular. At least, that's what Wirsbo's CDAM states. They also specifically note floor temperatures of up to 87.5 degrees are "acceptable", however I do not know under what circumstances they are covering there. 90 degrees is listed as the high limit for all floors. As a final measure, we limit floors to 85 max typically, but probably 95% of our systems use outdoor reset so the amount of time the floors are actually that warm is very small (i.e., only under design conditions). And the number of times we hit a 30 BTUs/sq ft heat load in the first place isn't as common as it may be for others as well, our clients are typically very energy concious.

Especially considering a large number of radiant clients are interested in the invisibility as much as any other aspect of radiant heating, I'm not about to put in second stage heat because a few percent of people in a rather mysterious study don't like it, for a few days a year. For the cost of secondary heating, you could add reset and have a much better system anyway.

Shaun Anderson

Would you

feel better on just doing a staple-up with Kitec rather than UF and Kitec ? With all the wallie responses its starting to sound a little shakey doing UF right with no one having done this system before. Thanks for all the feed back.

TheFuture

Unknown

Yes, I would. At least there is solid information out there on how staple-up performs.

However, again, if your loads are above 15BTUs/sq ft you should consider plates or some extra heat. maybe a bit more or less based on floor coverings.

Doc Radiant

Floor surface temps

What George is referring to is a chart in the ASHRAE Fundamentals book, on the optimum floor surface temperature for comfort. It's a bell curve with its peak at around 78 dgrees F., with 85 degrees well on the backside of the curve. Though I am not totally familiar with the methodology of the surveys used to arrive at the results, I think it's safe to assume that it was reasonably well designed and conducted.

Based on my own experience, I think 85 is OK, but is certainly at the limit of what I would want to be subjected to for extended periods of time with my shoes and socks on. If I'm wet and naked coming out of a shower on a cold winter day, 90 would be OK for the few minutes it would take for me to get dressed and get out of the bathroom. Higher floor surface temps may be OK as well for areas like mud rooms or foyers where I won't be hanging out for long.

But for those areas where I will be standing/sitting with my feet/socks/shoes in contact with the floor for extended periods of time, the 80 degree range is optimal. If I'm running outdoor reset, 85 may be acceptable as a temporary max temp for those short periods of time that the system is running at design conditions.

As is always the case, YMMV (your mileage may vary).

And if memory serves me correctly, I was the one who gave that RPA seminar George is referring to. But then again, it was a long time ago...

Jim Erhardt aka "Doc Radiant"

Shaun Anderson

I'm going to do a

new heat-calc with the Ipex software. Just to make sure everything works out. Better to do it right the first time or not at all. I don't want my contractors install photos to end up on the wall showing a job that just plan didn't work. We get enough of those. Thanks to all the wallies for not bashing me. Dead man in training.


TheFuture

Ragu

Mr. Future

UF seemed to just appear out of the blue at the supply house around here about 6 months ago; I STILL don't know anybody who has used it. This is at least the third time I've followed a long thread on The Wall about UF; I still am not interested in it.

I've read and re-read the above posts from some pretty knowledgeable people on the subject, and the general response has been: "No".

My gut tells me to stay with tubing that is in direct contact with the floor, use plates and insulate as per specs. Good luck.

Bill Pidgeon_2

"Try to install the panel rads so that they "see" the glass,
e.g. not beneath the windows."

This statement really bothers me. I'm only a homeowner, and I'll admit to being a little obsessive about efficiency, but placing a radiant panel where it sees the glass sounds like a great way to transfer heat to cold objects outside, or worse, the universe if the panel can see Space through the window.

Big delta T, but open windows and doors will do the same, while doing nothing to aid comfort. So, what am I missing?

Bill

rb_6

surface temps and outputs

The topic of surface temperatures and outputs was addressed in this link.

Click here to go there

an excerpt from the original post:

"The graph below shows the minimum and maximum recommended surface temperatures to satisfy 90% of the occupants in the room. At 84 deg F and a dry bulb temp (assumed equal to operative for this example) of 70 deg F there would be a 14 deg F delta T x 2 Btu/hr/sf * deg F = 28 Btu/hr/sf output based on comfort. When 68 deg F is used the potential output becomes 32 Btu/hr/sf which is where the rule of thumb comes from. However the higher one drives the floor temp the greater the output but at the risk of making people uncomfortable... eventually if the temperature becomes to hot it becomes unhealthy. ( see European Association for Phlebotomies Study from 1966 ) and if one operates the room at 68 deg F with over 3 ft/s air velocity the folks will also start to complain about drafts…and people think this stuff is just so darn easy…"


...the point being... continuously run occupied areas hotter than a nominal 84 deg F if you’re looking to see how good your lawyer is…or another way to say it is - lawyers will love it when they get called into a lawsuit where a floor has been delivering more than 30 Btu/hr/sf...

Any firm publishing excessive Btu/hr/sf outputs in occupied spaces and using it as a "I can get more from the floor" sales pitch is...___________(go ahead you fill in the blank).

The second photo is taken from the original research facilities that generated the data for the graph and subsequently used in ASHRAE Standard 55 and ISO 7730...I’m sure you guys will like the test models!

rb_6

test models in their underwear

...in case you were wondering what the lovely women are doing in their underwear...

Well...if you go to ASHRAE Std 55 or the Thermal Comfort Chapters of the Handbooks you'll see a list of "clo" values that get tied into predicting comfort...so if you want to test humans and comfort and clothing - well you have to do the test! Dr. Ole Fanger and his researchers had a tough job!

I would say these radiant darlings were the true Ultra Fin’s but not to be - they were Danish…

George Peteya_2

Sorry I took the Ultra-Fin Thread Off Topic ...

... but when I see those high design maximum floor surface temps, I feel a rant coming on. Jim, I should have named you as the source of the chart!
Just want to share an experience here. About 10 years ago, I worked in a radiant heated office. I was the only one allowed to touch any of the controls. The office was about 6000sf, parquet floors, no carpet. If anyone were uncomfortable, they had to come to me (don't EVER get yourself into this situation!). Whenever the floor got over 78°F., people took off their shoes (no dress code). Over 80° or so, they complained. This is admittedly different from residential applications, because our feet tended to stay in one place a lot, as we were at our workstations. So, you ould probably get away with higher floor temps in residential jobs ... I'm just leery from this one job.