heating system myths and theories

[davfox]

Dear jeff
i spoke to you several weeks ago about my new build next year, to which i am very grateful for the time given and information i recieved. However i do have a dilema, and i think i am not the only in this situation. What heating system should i go for. I am not asking you recommend a system outright, (that is not your perogative) but i do believ that construct ireland is in a superior position to stamp out once and for all the myths and theories i am hearing from people. I will give you an example. geo thermal will only work for a few years in this country because the ground will lose its heat over a couple of years and not be able to regain it. ufh is expensive to run, "i know a guy who put it in and is now putting in rads because he cant afford to run it".
i could go on and on. i am sure you know where i am coming from on this.
I appreciate the build itself, (insulation, elimination of cold bridging etc) is the first and formost priority, but i can really see yself having cold feet and just putting in an oil boiler, and i feel i would be saying in a few years time "why did i listen to all these bar room advisors. I challenge Construct Ireland to have the initiative to do an FAQ sort of thing to put some sort of standard on new heating technologies, (new to ireland that is) . P.S. saying that something works in scandinavia would not really cut it as the climate in summer and winter is different, and this is why poeple think it wont work here.

[heinbloed]

Here is an Excel sheet published by the SEI which might be helpful. But note the publishing date (2005)- solar power became cheaper in the meantime, other fuels went up.
http://www.sei.ie/index.asp?locID=58&docID=1
Go to "Tools-Fuel Cost Calculator"
then click on "Domestic Fuel Comparison Tool"
and the sheet "home heating cost comparison" should open.
Good Luck.

[galwaytt]

Well, realise that I am in the MMC business, but the following is a persona perspective, based on having UFH for 10 years - long before the current wave of interest.

In my personal experience, there is no penalty for running UFH at all. In fact, I'd wager the opposite.

If you think about it thus: your house will have a specific energy requirement to bring it to (your, personal) comfort setting. Irrespective of the delivery of that requirment (rads/ufh/etc), the nett requirement is the same. If you find that one delivery method is costing more than another, then there is possibly an issue with either the installation (quality of, e.g. integrity of insulation on pipe runs, perimeter insulation, treatment at cold spots such as doorways etc), the controls (you really do need to spend some time choosing, and setting them up), and also (to a degree) compatability of the heat source itself.

And the last point is very important, imho. UFH by it's nature, requires lower temperature water than rads. Some heat sources cannot modulate (e.g. oil), and therefore produce very hot water, which then has to be 'mixed down' to an appropriate temp, for use in the floor. To my mind, this is a fundamental waste of energy, heating up something, and cooling it to use it. However, other sources e.g. gas, solar, aero, and indeed geo, lend themselves to such moderate temp systems well. Geo, I feel (and it's only a personal opinion), is too expensive, and I believe not quite suited to our climate. Wood pellets offer potential, but I'm afraid I think there are still too many issues over equipment pricing, pellet quality of supply, and actual installation/storage. That's why I didn't put it in my new house - but I did leave a connection for when the issue IS solved.........

And I would never, ever, advocate mixing rads and ufh. If you think about it - you have two (competing) heat emitters, with different performance requirements..........but connected to a common heat source. It is just bound to drive you........crazy!

And not everyone likes a 'hot' or 'cool' house. If, like in mine, the ultimate barometer is what the SO likes, well then.........hey, what you really need is to 'take a test drive' in a potential house - but that's not always possible !!

My experience of gas + ufh down + rads up, led me in my hew house to put in ufh up & down, with gas and solar. My system is expandable for the future to allow other sources, or expansion of the existing.

We have a test house in Athenry which has aerothermal heating providing all space and DHW to ufh on ground and 1st floors, and rads on 2nd floor (oversized...!), just to see what it can do. You are free to see/touch/feel at any time ! (and I have no connection or interest in heating systems), but you would at least get an idea of what's possible.

btw, we have a separate meter on it, and it is costing about Eur75 per month for all space and DHW in this temp, and about 55 in milder ones. House is 100 sq m semi-D

Hell, I might even rent it to you for a long week-end !!

[sinnerboy]

We have a test house in Athenry which has aerothermal heating providing all space and DHW to ufh on ground and 1st floors, and rads on 2nd floor (oversized...!), just to see what it can do. You are free to see/touch/feel at any time ! (and I have no connection or interest in heating systems), but you would at least get an idea of what's possible.

btw, we have a separate meter on it, and it is costing about Eur75 per month for all space and DHW in this temp, and about 55 in milder ones. House is 100 sq m semi-D

Hell, I might even rent it to you for a long week-end !!

this interests me Galwaytt .

what was the install cost - i mean the air to water (ATW ) specific parts , not including UFH pipes ins + screed

what size ( physical ) is the ATW unit and how much "clear space" does it need around it

is the ATW unit noisy ? ( or does that matter next to the lonely fields ? - sorry couldn't let that pass :-)

do you think this may be an option in suburban sem-d land , generally ?



....... oh and how much foe the weekend stay ? ;-)

[galwaytt]

the system is a NIBE 360, and iirc, cost about Eur 5k. It's a self contained unit (looks like a big fridge.........)

I think they're perfect for semi-d land, up to about 100 sq m. Bigger than that, you'd need to talk to NIBE.

Not noisy. Well, can't be heard over the Surround Sound, anyhoo :p

[chavis]

Dear jeff
i spoke to you several weeks ago about my new build next year, to which i am very grateful for the time given and information i recieved. However i do have a dilema, and i think i am not the only in this situation. What heating system should i go for. I am not asking you recommend a heating system (http://www.techstore.ie/hometech/Heating-Systems.html) outright, (that is not your perogative) but i do believ that construct ireland is in a superior position to stamp out once and for all the myths and theories i am hearing from people. I will give you an example. geo thermal will only work for a few years in this country because the ground will lose its heat over a couple of years and not be able to regain it. ufh is expensive to run, "i know a guy who put it in and is now putting in rads because he cant afford to run it".
i could go on and on. i am sure you know where i am coming from on this.
I appreciate the build itself, (insulation, elimination of cold bridging etc) is the first and formost priority, but i can really see yself having cold feet and just putting in an oil boiler, and i feel i would be saying in a few years time "why did i listen to all these bar room advisors. I challenge Construct Ireland to have the initiative to do an FAQ sort of thing to put some sort of standard on new heating systems, (new to ireland that is) . P.S. saying that something works in scandinavia would not really cut it as the climate in summer and winter is different, and this is why poeple think it wont work here.
hi,
Heating systems are very important here in the Ireland. With the long cold winters, it is imperative to have a reliable source of heat. After all, your heating system keeps you warm and ensures that you have hot water for showers, laundry, and dishes. Legal ordinances have changed quite a bit over the last fifteen years. Luckily, with these changes newer and more energy efficient equipment is now available for your building.
Replacing your existing radiator or boiler can greatly reduce the amount you will pay for heat. Today’s heating systems are over 50% more efficient than those available twenty years ago. In many cases, the amount you save on energy cost will cover the cost of replacement within a few years.
You can often have a much warmer home or office for only a fraction of the cost.

[psytek]

does anybody use rocket mass heaters?

[PaulK]

I think this is not a one size fits all question.

I teach a sustainable heating module in a third level college (night course). As part of this course we get all the students to work out the cost per kWh running and cost per kWh over 10 and 20 years and ask them to make a comparison.

before the heating module is the passive solar design, and every student realises that the true secret is to design out heating requirements if you want to have a truly sustainable heating system!!

cheapest kwh cost = log boiler, but lots of work!
least work, low running cost = GSHP, but very expensive!


listed building without possibility of low U values = > wood pellet boiler, wood log boiler if you can do the work.

passive house with mHRV = > HP or Wp stove with bagged pellets.

something in-between = > do the maths!

[Adrian Hennessy]

passive house with mHRV = > HP or Wp stove with bagged pellets.


id question that....

did they calculate out the costs of HP or WP stove versus Electrical element in MHRV system???

WP stove requires separate wet distribution system for heat, very expensive compared to practically nil for electrical element. Cannot see that at all as being economical for a passive house.

HP air to air can be distributed through MHRV system, but has higher initial installation and unit costs, although may be cheaper running costs.

[daisyheating]

I surely agree to those who advise you installing underfloor heating system. We're a manufacturer in China for underfloor heating system, and as far as we know, more and more persons in Ireland fall in love with this comfortable, environmental and money saving system.

if you need more about the technique, please send me email: daisy.ppr@hotmail.com

[myley]

does anyone have experience with a vhrs, im trying to decide which copany to go with, its looking like either ATC or Nuaire, but i cant make up my mind which would be better? also for my insulation im torn between a full rafter fill of either blown cellulose or icyene water blown and then intelo membrane on the underside between the insulation and the plasterboard.. the only thig im worried about is that i didn't counter batton both ways beneath the slates, but i pushed conduit up between the rafters to try and prevent cold bridging as it will sort of keep the falkro breathable felt away from the underside of the slates, i would appreciate any feedback on either of my 2 concerns.....