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    • CommentAuthordovecote
    • CommentTimeAug 19th 2012
     
    I am trying to understand the pricing difference between UFH packages and buying the system components yourself for a heating engineer to install.

    Even when I am looking at providing the materials myself for the engineer to install, packages from the reputable companies seem a lot more expensive than if I went to an online store. Naming no names, one such company quoted me £1600+VAT for a 39m2 package to run in screed; this is just the components - not the fitting or screed. It included the manifold. Yet online stores are offering 'packs' at less than half that.

    So what's the likely difference? It could be the 'design' service but in my case I have a single 39m2 area that maybe requires two zones.

    Could it be the pipe quality?

    Has anyone had experience with buying UFH 'off the shelf' for a basic setup? If so can you recommend any brands, especially for the pipe that goes in the floor?
    • CommentAuthorclovercott
    • CommentTimeAug 19th 2012
     
    That quote seems quite reasonable, I paid £2100.00 including vat for a 50sq mtr with three zones for all the components, Dont know if the forum allows me to mention john Guest speedfit but I can selep well in my bed knowing that I used good tackle.Its like the beer advert reasuringly expensive! By the way underfloor heating companies do not recommend any zone larger than about 20sq mts
    • CommentAuthorPugliese
    • CommentTimeAug 19th 2012 edited
     
    Have recently done a lot of research on UFH manufacturers and quizzing the installers around here one name kept on coming up, the german owned Robbens because of the quality of the components and excellent service. There was such a ground swell of positive opinions, I have just ordered a Robbens system.

    Forgot to add I also chose them because they have been doing UFH sytems since 1992 and they have an insurance backed guarantee that has never been claimed on.
    • CommentAuthortony
    • CommentTimeAug 19th 2012
     
    I would never do anything other than buy all the necessary bits separately, I don't like parting with money I dont have to part with.
  1.  
    I had 3 companies quote for my UFH and all insisted on a design output of 50W per sq M at a flow temp. of 30 deg C. even though my heat loss calculations suggest a max. demand of 15W per sq. M. at an ambient of -10C. so in general they were specifying 3 times the amount of pipework that we required.

    In the end after consultation with my house suppliers they suggested a layout of four loops of 16mm pipe each of equal length of 60m and treat the entire ground floor as one zone. They said that where they are installing the slab themselves (in my case they weren't) this is what they always do and they say it works well.

    Approx. half my ground floor is one open plan area so I don't foresee major problems in this approach but will have to wait and see. As a very well insulated and airtight house I expect that it should all sit at roughly the same temp.

    The total cost saving for supply and fit with this layout was about £5,000 compared to what the cheapest of the other designs were and about £8,000 compared to the dearest.

    The pipe and fittings that were used are big brand name stuff but I can't remember which one off the top of my head.
    • CommentAuthorcrusoe
    • CommentTimeAug 19th 2012
     
    Should be around £1200 + VAT for that size. MAX. Post is short as I have history and have to reduce post length. This is a start. If needing suppliers, whisper me. Robbens are as good as their pipe, which is Pe-X, as many are. Good rep, yes, but no better than many others. And I have been fitting UFH - Pugliese - (you sound like an Italian canine, not sure why....) since the early '80s.
    • CommentAuthordovecote
    • CommentTimeAug 20th 2012
     
    Crusoe - is that £1200 installed or just the parts (excluding edge insulation & screed - which we already have)?

    So are we saying that the difference in cost between the specialist packages and the online 'sheds' (i.e. ultracheapufh.com) is the quality and design service? Some of the sheds seem ok ...
    • CommentAuthorclovercott
    • CommentTimeAug 20th 2012
     
    Sorry for mistake, my cost for the UF package using speedfit it was actually £1200.00 not £2100.00, very happy with the result I installed the manfold while my wife laid the loops see picture Best of luck with your project.
      IMG_0175.JPG
    • CommentAuthorGreenPaddy
    • CommentTimeAug 20th 2012
     
    If you've only got a couple of zones, buy your own pipe, add a couple of 2 port honeywell valves, and a few other bits and pieces for control. I never buy manifolds, and certainly not kits. Pipe is about £1/metre, and the other bits are not expensive. It may be more than a DIY amature could design, but not complicated, and the cost would be around £200 per zone. Worth considering?
    • CommentAuthordovecote
    • CommentTimeAug 21st 2012
     
    Thanks all for the comments so far.

    Has anyone seen Nu Heat's One Zone package? I hear what you are saying about avoiding complete packages, but Nu Heat's pricing doesnt look too bad ~£750 + VAT with all the bits; the assumption being that they have taken some of the guesswork out of the process.
    • CommentAuthorHairlocks
    • CommentTimeAug 21st 2012
     
    I paid nu-heat £3000 + VAT for a 14 zone system, bit of a battle to zone each room seperately as I had been quoted. The manuals they provide are very good though.
    • CommentAuthorcrusoe
    • CommentTimeAug 21st 2012 edited
     
    clovercott - nice pic! When you say you are very happy with the result, do you mean the appearance, or performance. It's just that the pic is dated May this year, so wondering how much use you have had? Also your membrane atop the insulation reminds me that on a recent big UFH install, the flo-screed people wanted an extra membrane. I'll start a new thread to avoid hi-jacking. I never hi-jack :bigsmile: Unless he's a friend.....

    The 20 m2 rule is based on 5 linear metres of pipe per m2, so 100m max length. You can go over this, but it pays not to go too long as performance will diminish, while pump noise increases - and pump life expectancy decreases inversely.

    dovecote: That would be fitted - caveat - if local installer on reasonable margins.
  2.  
    Crusoe , polythene on top of insulation is spec. by manifacture of PUR board to protect it from degrading as a result of contact with screed.
    • CommentAuthorjamesingram
    • CommentTimeAug 21st 2012 edited
     
    I'm with Tony and greenpaddy, buy the bits and make up your own ufh sys.
    I make up my own manifold, pump , control values or use the single room units for the area you've got
    Most claim up to 30m2 but easier to push them up to 40m2 , especially if you've a well insulated home
    so can increase pipe spacing to 200mm.
    check out the budget range kit at scre*fix £570 or £750 ish for UK brand

    If you want to go super cheap buy 2 x 120m coils ( alway use excess for other jobs) go for 2 uncontrolled zones via a 15mm T and get one of these for £50 ish and plumb it straight into your flow and return off a rad.
    http://verwarming.danfoss.com/PresentationFiles/625_vd31a102%20data%20FHV%20eng.pdf
    • CommentAuthorcrusoe
    • CommentTimeAug 21st 2012
     
    Hi James

    This will be the subject of the new thread. Cheers.
    • CommentAuthoralec
    • CommentTimeAug 22nd 2012
     
    if you are putting pipes in screed it is always a good idea to put as much in as possible...once in you can run the system at a lower temperature with the same result..

    the other thing to "design out" are the manual mixing valves...a much better effect is achieved by using modulating electric valves with compensation room controllers..
    • CommentAuthorTimSmall
    • CommentTimeAug 22nd 2012 edited
     
    Posted By: aleca much better effect is achieved by using modulating electric valves


    On this topic, are there any you recommend?

    I'd thought of using 24v thermo-electric (i.e. wax capsule + heating element) ones, but I suspect that controlling them accurately from the software I'm going to write will be a project in itself - they have inertia, and I suspect they're also susceptible to changes in both ambient air temperature, and the water that's flowing near them too...

    Motor on / motor off ("mo-mo") valves would be much easier, but I didn't find any UFH ones (only radiators, and it didn't look practical to fit them to a UFH manifold).
    • CommentAuthorfinny
    • CommentTimeAug 22nd 2012
     
    First two systems I installed were nu heat packages as I was just a subby..never looked back, they way overcharge for the design element of the job. Although there is quite a bit to take into consideration, I would say anyone could get there head around the principles involved. Sadly some just seem to jab the pipework down in a random pattern which they may regret once it is screeded. BPEC do a engineers design course which is far too involved for most but it's worth asking for advice if you have no idea.
    • CommentAuthorcrusoe
    • CommentTimeAug 22nd 2012 edited
     
    alec - I respect your opinion but would beg to differ on the manual mixing valves. I have had better results and a more controllable system with MMV and independently-adjustable balancing valves in mid-size zones of 2-3 loops rather than 1-loop, 1-zone actuators. The theory's great for economy, the practice hasn't proved so IME. And several times more customer complaints with the electric actuators. Any time a customer feels they have no control, they (often) don't - and it's more than my life's worth.

    Caveat - many of the modern, DIY-type UFH setups don't supply balancing valves.
    • CommentAuthoralec
    • CommentTimeAug 23rd 2012
     
    I use vaillant and viessmann but you have to use their boilers, there are some Open therm mixing valves available...TEM come to mind, they can be used with any Open therm boiler...

    I dont think user invention to give control and UFH go hand in hand... because of the nature of the heat and the slow response time.

    I find that people go mad with all the zone controls, and one controller for a bigger zone is much easier for people to understand...couple with of course the fact that electronic mixing valves are kinder to the heat source as the whole system is properly integrated....

    When customer complain to me I ask them to measure the real temperature with a stand alone thermometer... and tell me what the deviation is ... that soon seems to shut them up!
    • CommentAuthorcrusoe
    • CommentTimeAug 23rd 2012
     
    Mmm - your third paragraph appears to agree with my second sentence. Same track roughly.

    So you get customer complaints do you? Cowboy!! :bigsmile::devil:
    • CommentAuthoralec
    • CommentTimeAug 24th 2012 edited
     
    I don't think you can do this job (heating installer) with out managing customers expectations. The problem is that people think they can...you can certainly design in reliability and efficiency..

    the selling and installation of technology is fraught with complication... but that includes computer systems, aircraft and heating systems...anything really where technology is used. I have an on going war with my V-box from virgin media for the television... all very hit and miss..

    The customer is not always right when it comes to heating...and fuel efficiency... there is no research for example that says turning things on and off in a regularly used building saves energy, yet people love their zoning!
    • CommentAuthorcrusoe
    • CommentTimeAug 24th 2012 edited
     
    Eh - and I thought the customer was always right....:wink: You are spot-on there IMHO.

    Zoning is a different issue. Which needs a different solution for every building. When we fitted the Mk 1 version of Honeywell's CM programmable stat range back in the late '80s, they produced research, aided and abetted by the government's own, now-famous, DOE research (1 deg C drop in temp saves 10% of your fuel bill) which said that their machines, avoiding the hysteresis caused by the on-off cycles you mention, could save upwards of 15% if used sensibly. My experience with customers ever since makes me agree.

    The on-off-or-not argument is polemic, as you can still save by going lower-higher (temperature stepping) without switching off per se. In other words, the temperature rather than the time has the final say. And you don;t always have to bring the temperature 'back up' again - the Jet take-off analogy, as your body can get used to lower temperatures, assisted by parts of a dead sheep wrapped around you...

    Zoning allows you the luxury of experimentation, is good where you have different temp requirements in different parts of the house and/or at different times of day, allowing small, regular temperature changes. It is therefore flexible and good for the soul as well as the pocket. I could go on for days and have frequently been known to....

    So yes, I guess you could say I love my zoning. :bigsmile:
    • CommentAuthorTimSmall
    • CommentTimeAug 24th 2012
     
    Posted By: crusoeAny time a customer feels they have no control, they (often) don't - and it's more than my life's worth.


    There's a solution to that - placebo controls... I've met people who've successfully deployed them (simple analogue bi-metalic strip stat, connected to nothing).
    • CommentAuthorTimSmall
    • CommentTimeAug 24th 2012
     
    • CommentAuthorcrusoe
    • CommentTimeAug 24th 2012
     
    Thanks for the tip Tim, won't be trying that one any time soon. I can visualize the conversation...."Trading standards here Mr Crusoe, now about that non-connected CM9000 you fitted at Mr Small's..." :smile:
  3.  
    Guys,

    The other question which I never really understood 10 years ago when we put our first UFH in was if you should use pipe with a oxygen barrier or not? It was a lot more expensive at the time so we just used standard plastic PEX pipe. Is that still an option or are all pipes now with O2 barriers?
    • CommentAuthoralec
    • CommentTimeAug 25th 2012 edited
     
    Crusoe...see new thread about zoning.


    Yes you must use PEX piping precisely because of the oxygen barrier...especially if there are radiators on the same circuit...or if its too late then a plate heat exchanger to hydraulically separate the two circuits can be used...
    • CommentAuthorcrusoe
    • CommentTimeAug 25th 2012
     
    That's the theory Phil, though I suspect that, among the hoi-polloi of the plumbing world, many non-barrier pipes have been used for UFH and central heating, before barrier pipe came along! Exactly how much lifespan a barrier pipe adds if the system is well-inhibited anyway I have no idea. Nor, I suspect, do others. Unless somebody can point me to a study?
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