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Solar questions

hot_rod
hot_rod Member Posts: 22,024
supporter here, always have been.

But there is and always will be a room for solar supplied through the distribution chain, also. Plumbing and HVAC wholesalers make a commitment to stock, support, train, warranty products. Yes it does add some cost to buying direct for someone in China.

Many contractors and installers feel more comfortable dealing with suppliers they have a long history of doing business with. Someone they know and see in their community on a daily basis. Not everyone is driven by the lowest possible purchase price.

I see even Wal-Mart has dropped their "Everyday low prices" spiel :)

hr
Bob "hot rod" Rohr
trainer for Caleffi NA
Living the hydronic dream
«1

Comments

  • Wayco Wayne_2
    Wayco Wayne_2 Member Posts: 2,479
    I've been slowly

    getting my system together for my solar project. I've been too busy with work to make much progress but I'm getting there. I've been watching the sun on my SE roof and the sun is low in the sky and behind the tree line. I get some direct sun but a lot of diffused sun though the branches. I thought it would be better once the leaves dropped and it is, but I'm concerned about not getting enough direct sun. I've heard evac tubes are mo better in diffused light situations, but I wanted to do a drainback system, so that means I have to do flat plates. Would the Buderus Flat plate filled with Argon gas be better than a regular flat plate for diffused light. Is there any worries about in losing it's argon over the years. Once the sun rises higher in the sky I'll get a lot of dirst sun but I wanted to do some heating with it too, not just domestic water. Any input from more experienced folks would be appreciated. WW

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  • Todd S_10
    Todd S_10 Member Posts: 1
    Solar Pathfinder

    You may want to try using the Solar Pathfinder. This device will show you what your yearly sun exposure will be. Its a pretty simple and slick device check it out here: http://www.solarpathfinder.com/

    As far as the Argon question, I can't offer any advice, but I have heard of disappointing results with windows constructed with this barrier.

  • Wayco Wayne_2
    Wayco Wayne_2 Member Posts: 2,479
    Thanks Todd

    I guess I'm just worried about the diffused sunlight coming through the leafless branches of the trees being is diminished to the pint of being a problem. I just don't have a feel for if it's problematic or not. I read that evac tubes are less affected by it and wonder if I should change my design to them or not. On the other hand I crave the low maintenance of a drain back system and would get that from a flat plate. WW

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  • Mark Eatherton
    Mark Eatherton Member Posts: 5,853
    Argon and windows.

    I have it from a very reliable source (window manufacturer) that Argon will leak out of a window unless it is 100% air tight. I would assume that the same would be true of solar collectors.

    Who is going to climb up on their roof, say 5 or 10 years from now, to draw a gas sample to see if the Argon is still there?

    Although it may have shown good results in the lab, the real world is a lot different. After being man handled from manufacturer to and through distribution to the final resting place on the roof, it HAS to leak.

    ME
    It's not so much a case of "You got what you paid for", as it is a matter of "You DIDN'T get what you DIDN'T pay for, and you're NOT going to get what you thought you were in the way of comfort". Borrowed from Heatboy.
  • Wayco Wayne_2
    Wayco Wayne_2 Member Posts: 2,479
    I stayed up

    past my bedtime last night reading Toms Lanes Lessons learned. Specifically the chapter on collectors. He's pretty adamant on the point that flat plates and evac tubes are pretty much the same as far as capacity and solar absorbing capabilities. The only difference being when the water temps get up high, the evac tubes are mo better because of the insulation factor of the vacuum. My solution is looking more and more like a chain saw. Hahahahahaha! But my wife is standing in my way. She loves the trees and is their champion. Let the negotiations (begging) begin. WW

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  • CC.Rob_12
    CC.Rob_12 Member Posts: 1
    tree trade

    Offer to trade 1 tree on the south side for 1-2 new ones on the north. Or trade taking down something above the roofline for something in that area that will take a decade or two to grow above the roofline.

    It works....
  • Ron Huber_2
    Ron Huber_2 Member Posts: 127
    oversize

    I use Solmetrics Sun-Eye for evaluating the solar potential of a site. An expensive tool but if you are getting into the business of solar installs it is well worth it. It takes a digital shot with a fish eye lens, calculates the location geographically,shading from trees(you can see which trees are the biggest problem), southern orientation, then gives you a percentage for each month that you will get for solar gain. When I run into your situation I add a panel.
    square foot area of evacuated tubes has been overstated, you get just so many btu's per square foot falling on the earths surface, flat plates are less expensive and will do just as good as the tubes. I have a 30 tube system on my own house and I will be adding another 20 to 30 tubes to it or replacing them with flat plates because of the lack of production compared to what I was expecting. We have installed 20 flat plate systems and three evac. tube systems since June and price vs. performance the plates are kicking butt.
  • hot_rod
    hot_rod Member Posts: 22,024
    10% of nothing is still

    nothing. And that is the challenge. If the leafless trees block what little energy is available from the cold, sunless, winter sky then a collector that is MAYBE 10% more efficient is a mute point.

    In my mind when you add up all the questionables surrounding evac tubes, like longevity, able to keep fluid in the heat pipe, transfer through the condenser, warranty, etc. it's really hard to beat flat panels with 25 plus life expectancy, probably more.

    Adding square footage, as Ron mentioned would be better than adding double walled glass and vacuum spaces.

    I've read leaf-less trees can block as much as 50% of the solar radiation in winter months?

    Evac tubes do provide hotter temperatures as they lose less to the cold ambient air in cold conditions, due to the better insulation provided by the double glass and vacuum space.

    A lot has to do with the operating temperatures you plan on running and the ambient air.

    Our calcs show about the same performance between tubes and plates at 100- 105F supply, 20F ambient air, 200 BTU/ sq. ft. radiation. Colder conditions or higher temperature requirements, the tubes are stronger.

    This website will show you how much energy is available on a monthly basis in your area.

    http://rredc.nrel.gov/solar/pubs/redbook/PDFs/MD.PDF

    hr
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Wayne you can

    use silicon solar vac tubes with drainback. They are excellent collectors with a very high srcc rating and yes they are made in China just like the German ones but at half the price. Check them out at siliconsolar.com.
    Also the tilt frame is included with the collector.
    TONY
  • Flat plate vs. tube

    I have installed both type now Wayne and from my experience I have found that the advantage in vac tubes doesnt lie in their ability to collect more energy but rather from the installation standpoint. The glass doesnt get installed until the whole system is finished and tested. Wind is not near as relevent being able to easily pass through the tubes, a flat plate will fly you right off the roof. If I drop a wrench or a branch flys off a nearby tree it breaks a couple tubes without even shutting the system down..20 bucks a tube, big deal. A broken flat plate is a major pain in the ****. Also the tubes seem to make the customers feel like they are getting new technology and not some old 70s tech they heard so many horror stories about. Also there is no reason for some of the ridiculous prices out there. The old supply chain method of manufacturer(who actually imports)-rep-wholesaler-installer-customer are just not reasonable here.Go to alibaba, there are hundreds of suppliers just waiting to sell directly to You. If we really want this stuff to be mainstream and not just for wealthy people to show they are Green we have to make it really affordable with a very short payback. Just my opinion.
    TONY
  • hot_rod
    hot_rod Member Posts: 22,024
    Wind noise through tube collectors?

    I'm hearing reports of howling noise across evac tube collectors? Reminds me of when I carry an extension ladder on the top of my truck :)

    I wonder if it could be the U shaped collector frame work, causing the noise or the collector tubes themselves?

    In my 30 years in the solar installation and service industry I've seen a handfull of glass replacements on flat plate. Tempered flat panel glass handles all but the largest of flying debris.

    Anneled evac tube glass is much more brittle and sometime breaks in shipping.

    I see a couple manufacturers touting larger diameter, thicker walled evac tubes now. Must be a reason to increase the glass thickness?

    Tony, tell me about these 20 dollar evac tubes? Manufacture, warranty, how long on the market, etc.

    hr
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • rt_2
    rt_2 Member Posts: 86
    Evac Tubes

    I've had two 25 tube systems on my garage roof since June and I haven't heard anything as far as wind noise. We've had winds up to 40 MPH. Two days ago, it was 18 degrees @ 9:00 AM in the morning here in NH. Within a half hour, the temperature up on the collectors went from 18 degrees to 80 degrees and climbing. The sun is filtered a little this early in the morning from leafless trees. They're working for me. I have no complaints or regrets thusfar.
  • Hot Rod

    here is a link to sunmax solar page http://www.siliconsolar.com/solar-evacuated-tube-collectors.html

    I agree with Rene, I live in Reading PA. and we had very high winds about a week ago and I heard nothing.

    They also have flat plate panels at really good prices and they are undergoing scrr right now. Im not sure where you are located Hot Rod but silicon solar is in Bainbridge NY and they have a nice showroom with active units installed. You have to become a dealer to get dealer pricing but that is nothing for even a small mechanical contractor.
    I have been to a couple of these schools for the german units and Lets get real here, the ones I seen were plastic on the back, a sheet of low iron glass, 20 pounds of copper and a little insulation. This is not rocket science. And when I ask about their vac tubes ohhh like they are soooo special and only german engineers could possibly understand, yea right thats why all those wealthy chinese have vac tubes hanging off the side of their huts.Just the way I feel.
    TONY
  • hot_rod
    hot_rod Member Posts: 22,024
    Thanks Tony

    looks like they have a lot of info at their website.

    I did notice the SRCC performance differs from the info at the site a bit :) SRCC shows 28K at best condition, the ad shows 40K. But they do look to perform better than some of the other tubes on the market.

    Are they heat pipe or flow through? Hard to tell from the website.

    I'm glad they do run their products through SRCC. Plenty of imports out there without any listings. 90% of the market for evac tubes is in China. Upwards of 300 compainies manufacture tubes in China. I think Viessmann will soon built their tubes in China.

    hr
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Ron Huber_2
    Ron Huber_2 Member Posts: 127
    $20 a tube?

    1)In 31 years never had a flat plate "fly" off a roof. 2) Never paid less than $90 for a QUALITY tube and that is at my dealer cost.
    3) flate plate glass may be harder to replace, but you do not have to drain the system down to do it
    This sounds like you do not have a lot of experience in this field. Sorry Tony, but when I read posts from guys who give misinformation it really gets me going. If you have real information about a topic, you better be able to back it up, guys are looking for advice here, and the last year or so too many people have been coming up with info on solar that is either off the cuff or just plain silly. The "new" evacuated tube technology has been around since the early 70's and they have had more problems than flat plates have ever had. What brand sells for $20 a tube? Most of the tubes are from China, by way of Australia and Europe, and there are only two or three brands that I would put in and the one that I have been using has had their problems too. In the late winter of 07 there were tens of thousands of tubes that broke during a batch of hail storms in Europe that were more severe than normal. Check out the real performance difference between plates and tubes, May to October, when we get most of our sun to begin with, plates outperform tubes. The new Coating that the better flat plate companies are using (Blue Sputtered,Sol titanium)are outperforming the standard black chrome selective coating in colder climates by 10%.Unfortunately the standard that customers look at is payback when considering a solar system,and in that respect the flat plates "payback" several years before the tubes do. I sell and install both in the Northeast, here in NH we get 56% sunshine, November till late January we are in the dark so to speak, so the tubes have no big advantage here, they get covered in frost and snow and do not melt away for days,if the snow melts a little one day it turns to crusty snow/ice and takes forever to melt on their own. If you get serious about being in the solar business you go out and buy an electric ladder hoist and send the panels up the roof with the flick of a switch, I get two or three panels up there a lot faster than carrying tubes up a ladder one at a time, being very careful not to bump it against something and causing it to break. O.K. I'm done.
  • They have both

    Types Hot Rod. The units that have the scrr rating are the heat pipe units. However they also have flow through units that they refer to as thier u-tube units, They are less money and they do have some advantages over heat pipes. They can be laid flat or any angle..heat pipes need min. 21 deg. But they cant be used in drainback system. I have never installed the u-tube but I have seen them and have disasembled a tube on one to inspect it and they seem fine.
    TONY
  • wow ok

    Thats alot to answer, but ill try. Fly off the roof, ok what i meant was what any 4x8 sheet of anything will do when your trying to install on a windy day. 2. WOW YOU PAY ALOT. 3 I was refering to the roth flat panels ..you cant replace glass at all, along with others.4 I wasnt arguing about performance Ive read tom lanes book too. But I was saying for the guy that is going to put some panels up or try his first job and doesnt own a super duper electric ladder, vac tubes are easier. And all those ratings and sputtered titaniums I dont pretend to know what that proccess consist of but I do know how to go to the scrr web site and easily compare factual results with a little reading skill. I purchase tubes from Silicon solar...yes they are listed in srcc web site if you need to check thier sputtering technique, I aint typin all that. But I also belong to Alibaba .com I just listed as a buyer and everyday I come home their are flat plate and vac tube venders in china that try to sell me their systems at less money than what I pay.And Last Maybe its just my point of view but I really dont like going up on roofs, so I do it as little as possible, I send my proffesional, insured roofer sub up there and he mounts and seals. I try to stay true to my profession. When you try doing everything you end up not being real good at any one thing. And Im not afraid of heights ive been a pilot since i was 16...30 years. I just dont like being on roofs.Im done
    TONY
  • scott markle_2
    scott markle_2 Member Posts: 611


    Ron, I hope I'm not one of those silly off the cuff guy's you are talking about. I think it's OK for someone with limited field experience to have an opinion. Misinformation is another thing, but if things work the way they should here,someone usually steps in to question misinformation, And this process can often bring interesting things to light.

    I thought Tony brought an interesting perspective to this discussion. I have wondered about the "fact" that China leads the world in sq.ft of solar thermal put in service in the last 10 years. I'm pretty sure I picked this up at a class in Warwick R.I. Maby we can learn somthing from this? why is the evac tube approach so popular there?

    I find something very compelling about the use of solar technology in places like rural china. The batch collector with heat pipes immersed in an insulated storage tank is a very interesting mix of high and low tec .

    Necessity is the mother of invention. Solar really has much more to offer to the worlds poor than it does to it's rich. Solar cookers, PV for well pumps, and lighting, and dhw batch collectors offer tremendous potential to assist the life's of millions of worlds rural poor.

    My take on residential solar opportunities here is this: Forget about heating in most of the north-east. The exception perhaps being a project with excellent exposure and a holistic approach to the entire structures energy management.

    Small is beautiful, Wht try so hard to get from the sun what it does not offer easily. Size for a manageable summerDHW fraction, and accept what you can get in the winter. Don't forget that unless you are doing drain-back, the notion of adding more panels to a location with limited winter exposure could create storage and dump-zone headaches in the prime summer months.
  • Mike C._4
    Mike C._4 Member Posts: 56
    Solar questions

    Not sure I want to get into this discussion but.......I do have a 120 tube sunmmaxx array I installed on my own roof. The quality of the tubes/hardware is about as good as anything I have seen. And I have been to a few places to check evacate tubes out including China. As I understand about 5 companies make evacuated tubes and they are all in China. The tubes are tough. I manhandled them and didn't break one. They were subjected to almost gale force winds right after install and there wasn't any noise or shaking or anything. I would be concerned if a flat plate system were tilted up like my evac sytem the wind loading would have been much more pronounced. I have nothing against flat plate collectors but the installation was a big plus along with generating higher temps. I had 160 gallons of hot water up to about 160deg F here in northern Maine today. Without getting long winded the generally accepted data shows evac tubes will give more output during fall and spring with generally somewhat more overall during the year. I can't say the typical extra cost upfront and possible lifetime cost makes them worth the price difference. I am going to expand my system for heating. I have contemplated using flat plates along side the evac tubes for a controlled test but my wife would probably kill me at that point.

    Mike
  • scott markle_2
    scott markle_2 Member Posts: 611


    Tony,

    While I appreciate your angle, I had a brief look a the silicon solar offerings and I found some bad practices. Pex is almost universally considered unsuitable for solar applications, and yet their kits were pictured plumed in pex, with the comment that the installer should be familiar with soldering or making pex connections.

    This is such a far cry from the in depth professional literature and support that a company like Viessmann supplies with their products. It's kind of silly to make equivalencies. Cost is important, and yes it needs to come down. Considering how few traditional plumbing supply houses are actually stocking hardware, it is relevant to ask questions about supply chain inefficiencies. However, selling evac. tube systems directly to homeowners to install with pex tubing does little to advance this field.
  • Pex is not an option

    Silicon solar has been selling all types of solar since the 70s, And there has been a very small market for it. This pretty much left it to the manufacturers to sell direct. I agree most systems I see you can tell they were not formally trained pipefitters or plumbers. But they work. Its like a cross between the mother earth news people and licensed fitters with a whole buch of opinions thrown in. I have been in this business all my life.I am very well rounded mechanically, having even built and flown my own aircraft. I know junk when I see it and I know when Im just paying to much. Im sure any mechanic here could open a solar panel and point out what they like and dont like, and thats why we have srcc, to keep junk off the market.
    But anyway my point is, our country is in serious trouble, we must control our energy consumption. If we could get 2 panels on every roof in this country and Obama kicks in with 40 maybe 60% tax credit. We could seriously help put this country on the right track. Offering these systems at outragious prices is never going to help us out of this hole.
    The last thing I want to say is that I have never really been impressed with european design, they have been paying outragious fuel prices for many years and all their offerings is the best they can do...smart cars and modulating fossil fuel boilers pleeeese. Sure its clever and definately a step ahead but nowere near solving anything.
    TONY
  • hot_rod
    hot_rod Member Posts: 22,024
    Wind should not be an issue

    the panels I am familiar with handle 181 mph wind loads.

    It is up to the installer to assure the mounting is up to those conditions. Wood screws into plywood are NOT acceptable. The Florida energy Center and other associations have mounting guidelines. There are engineering companies in Florida that specalize in wind loads. After seeing recent hurrican damage in the south we all understand the need of codes and guidelines for wind loads. same for roofing and shingles.

    Solar panels are really no different than a carport, awning, gazebo, etc when it comes to wind.

    Personally I like to keep them mounted to the pitch of the roof, except flat roof of course. Take the output performance hit, or add additional panels.

    I find customers prefer the flat to the roof mounting, over awkward legs and braces and additional wind shear loads. I see more and more flat panels being flashed into the roof, these days for an even less obtrusive look.

    hr
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • scott markle_2
    scott markle_2 Member Posts: 611
    urgency

    Tony,

    I'm with you on the urgency of this situation. It's very obvious to me that widespread use of supplemental solar water heating is preferable to fewer high cost ambitious active heating systems.

    This might interest you. It's from James Hanson of NASA on the urgency of climate policy. Gets into some interesting ideas on a tax/dividend structure to curb emissions, and encourage alternatives NUKES included.

    Oops I forgot the link: http://www.columbia.edu/~jeh1/mailings/20081121_Obama.pdf
  • scott markle_2
    scott markle_2 Member Posts: 611


    HR,

    Problem is (on a low pitch roof especial)adding extra panels is going to exacerbate the already problematic issue of summer and winter performance differences.

    I believe a system should be designed so it is close to stagnation proof, without the use of dump zones or night time shedding. Adding extra panels have a negative effect in this regard.
  • Mark Custis
    Mark Custis Member Posts: 539
    I agree on the urgency

    I also agree on suplimental.

    I think thest solar bang for the buck would be a radiant floor or panel.
  • hot_rod
    hot_rod Member Posts: 22,024
    It's always about the load

    and certainly summer load when you start looking at solar options. Like any design you really need to look at a case by case basis.

    Location, solar radiation available, and the bigy being the summertime DHW loads. Summer vacation, etc.

    Four means to handle over-heat in a closed loop glycoled system.

    1 A solar controller with overheat function. This allows the tank to exceed the 140 setpoint and overcharge. it may be enough to handle some over heat concerns.

    2 Nightime re-cooling. many controls now include this function to run the pump at night to pull the tank back down to 140 setpoint. It's been very effective on the system at our location in Milwaukee with a 0% summertime DHW load :)

    3 A 24/7 pump operation. Move the control to hand on mode when the homeowner leaves town in the summertime. Just remember to put it back in autu when they return.

    4 Open the gravity gates, aka check valves, in the pump station. This allows nightime re-cooling without the need to run the pump. The Germans prefer it to using electricity to re-cool. Thermosiphon handles the transfer.

    Of course these methods only work with flat panel collectors. Evac tubes are a one way device, they don't shed heat very well.

    There comes a time when drainback makes more sense.

    If the array is grossly oversized for summer loads, I feel drainback has an important advantage in that respect. I predict this year will see a lot more drainback packages coming on the market.

    The 5/2008 issue of Sun & Wind Energy reviewed a bunch of drainback systems hitting the market as we speak. Even the traditionally closed loop loop Germans are seeing the light on DB systems :)

    I agree with the simplisty of the evac tube ICS or collector /storage that is very common in China. No moving parts, no controller, no pump, very inexpensive to build an install. Actually in many location these are throw aways. When the tank leaks or the collectors fail the entire system is replaces, just as we do with water heaters here.

    Their overheat protection involves letting the T&P valve in the tank pop off and taking on fresh cold water. Effective, but wasteful considering the cost of treated water in th US.

    Plenty of ways to skin the solar cat. it good to have a lot of options and the expertise to select the proper application for the customer. Solar like radiant needs to be designed to the application.

    hr
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • rt_2
    rt_2 Member Posts: 86


    Hot Rod,
    In your posting at 1019 this morning, in item 4, you mentioned opening the check valves. This would allow thermo syphoning at night thereby not needing the pump to move the fluid. I had this syphoning problem when I first lit off my system and it may have been you who said to install a check valve. I had a swing check and not a spring loaded check valve. After swapping check valves it worked. Do you or anyone else know if there is such a thing as a 3/4" spring loaded check valve with a manual overide so it can be opened manually? If there is, where can I purchase one?

    Rene
  • hot_rod
    hot_rod Member Posts: 22,024
    I learned

    the lesson about those checks and their importance on both supply and return.

    I happened to glance at my solar controller late one night and noticed the panel was still at 120F. Turns out one of the checks has some debris in it and it was thermosiphoning my heat away from the solar tank! A bummer because the top coil is conncted to my boiler for back up. so I was heating the night sky with boiler output via my collector.

    Here is a great valve used in many of the Solar Pump Stations. It is a well for the thermometers, a shutoff, and a spring check with 1/2 psi pop.

    They took it a step further and built it so the edge of the ball valve will lift the check when turned at a 45. This allows you to drain back the panels if need be through the checks.

    I'm not sure if that assembly an be purchased alone? It comes to us assembled and the supply side has the safety group built in. It's a straight thread also.

    You get a lot of bang for your bucks with these solar pump stations. Pump 3 speed Wilo, fill and purge valve, dual checks, iso valves, flow meter, air vent, temperature gauges mounting bracket, insulation jacket, etc. All built to withstand 300F plus temperatures. It would be hard to build all of that from off the shelf components.

    hr
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • Check valves

    B&G has what you are looking for. I have them on my hot water system and they are in the open position. I changed my system from 4 circulators to 1 ciculators and TRVs, workes like a champ.
  • rt_2
    rt_2 Member Posts: 86


    Thanks Ernie.
    I just got on their Web Site and E-mailed a local representative to see what's available. I couldn't figure out how to search for it on their Site.

    Rene
  • Excellent article Scott

    And as much as I hate to say it, the price of fuel coming down isnt going to help the situation. Even if they would add another buck or 2 tax to fuel to start a manhattan project energy project. I wouldnt like the pain but I know we need to do it. I would have much rather seen the 700 billion go to renewable energy. I hope for all our sakes Obama turns out to be a real leader and not just another politician with his hand out.
    TONY
  • rt_2
    rt_2 Member Posts: 86


    Ernie,
    You wouldn't happen to have a part number would you for a 3/4" spring loaded check valve with a manual overide? They haven't replied to my E-Mail yet. Hope everyone has a happy Thanksgiving.
  • michael_34
    michael_34 Member Posts: 304
    Once again flat plates Vs. evac tubes

    Most the repairs I do on solar thermal systems are evacuated tubes. The worst being Sunmaxx. I've posted before the problems with these (sorry folks who already have them).
    anyway here is a side by side real time data comparsion of the two. Note this is in Cloudy Ithaca NY.
    Copy and paste to your browser.
    http://cwc-das.com/wcsd//tabs.php?loggerids[]=485E700680A6C389
    Have fun.
    Michael
    Happy Thanksgiving!
    Go Lions!
    desert_sasquatch
  • Evac Tubes - China Ireland USA

    Hi Lads, I am an Irishman based in China and we source tubes, manifolds, pump systems and panels. Have read your comments with interest, here are mine.

    1) China is undoubtedly the best manufacturer of tubes and US20-15 is the correct price to pay, however you need to pick your partners and manufacturers carefully, also you need to hail test the product this side to ensure no problems your side - that's how we do it. Over 60% of tract housing China have tubes, these guys are good at it.

    2) Flat panels do come off roofs in the west of Ireland, if there is more than an inch gap underneath after installation (between panel and slate) an almighty gust of wind can lift them, but wind must be very strong, so the key is to install without a gap (or as small a gap as possible.

    3) Efficiencies vary from tubes to panels and from manufacturers to manufacturers and it's hard to compare apples with apples.

    4) USA SRCC - there is a massive backlog in their Florida testing center, does anyone know another area I can get some product tested and certified.

    Regards
    **** Casey
    dcasey@sustsourcing.com
  • hot_rod
    hot_rod Member Posts: 22,024
    good info

    still my question is about the life expectancy of the tubes. If within a year tubes need to be replaces even the very small performance, if any, difference goes away. Even with free warranty tubes, SOMEONE has to get on the roof and replace them.

    How does a buyer in the US weed out the good from the bad evac tube manufacturers? Certainly there is a difference between a Viessmann 100 dollar tube and a 20 dollar tube?

    As for testing collectors... SRCC actually does not do the testing. They use two labs, one in Florida one in Canada called Bodycote.(dot com))

    I believe Canada has some testing and certification outside of the SRCC, maybe start there.

    It would be helpful if the various listings would cross over DIN, Keymark, etc. Maybe some day.
    Bob "hot rod" Rohr
    trainer for Caleffi NA
    Living the hydronic dream
  • What Type

    of repairs are you talking about Mike?
    TONY
  • Rene

    Rene,B&G part #BG_107035 its listed on their site under parts. Have a Happy Thanksgiving,Ernie
  • rene_4
    rene_4 Member Posts: 27
    check valve

    Thanks Ernie.
    I check at their Web Site and it doesn't specifically say it'a a check valve but it sounds like it will prevent thermo syphoning. Is that right? I E-mailed a local rep to get a price quote.
    r
  • rene_4
    rene_4 Member Posts: 27
    check valve

    Thanks Ernie.
    I check at their Web Site and it doesn't specifically say it'a a check valve but it sounds like it will prevent thermo syphoning. Is that right? I E-mailed a local rep to get a price quote.
    r
  • Rene

    Its a spring loaded flow check to prevent gravity flow with the ability to open with a 180* turn. Works for me,Ernie.
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