Hello-- First: I just stumbled onto this forum the other day and have read lots of great posts here--it's obvious that there's a ton of experience and expertise on these boards. Thanks for a being a great resource. I live in a new (built in 2008) two story home located in Boulder Co. I am currently researching info for a radiant retrofit for the first floor. We currently have a FHA system that's noisy, aggravates my son's allergies, etc. This system would be the primary heat source for the first floor (above an unfinished basement which will eventually be finished into an additional bedroom and bathroom); the FHA would remain in place to heat the 2nd floor. First floor surface area is roughly 1250ft^2. * Im looking for an experienced professional in the area: any recommendations/referrals? * The builder installed a Rinnai R53 tankless for DHW; any recommendations about keeping this in place and adding an indirect tank versus replacing with a mod-con boiler and indirect tank? * Rather than replacing the Rinnai, any thoughts about keeping it in place and going with a dedicated closed system fed by another boiler? My concern about this approach is natural gas supply, additional space, etc. * I'm trying to rough-out costs for this project and figure that PEX, plates, mechanicals for 1 zone, plus boiler and tank will set me back $6K-7K. Considering I have full access to joists/spaces what's a ballpark labor cost? I traded emails with a contractor who guesstimated that this entire job would run $30-$35K (including all parts and labor) which, apart from the state of the economy, sounds insane. Thanks again, any comments or advice greatly appreciated. PP

Hello,
Saw your post, regarding the air system, a first do that is not a great expense is install a high quality air filter, we distribute one that is particularly good, Sun Pure.
http://www.blueridgecompany.com/radiant/hydronic/150/sun-pure-sp-200gs here is a link, this is a hospital grad filter, read about it. A good tin man can place it on the return air side with out to much cost. Because your plan is to keep 1/2 the air side this would not be wasted money and will prove immediate value to your son.
As to the in floor, your numbers are about right, If you can install the pipe and plates your self you may be able to find a contractor to connect the boiler and fine tune the system saving a fair sum of cash. If your satisfied with the Rinnai ( it is paid for and installed) and want to simplify the immediate work order simply place the condensing boiler. You now are addressing one temperature and one zone, easy. You will be able to come back with a side arm tank in the future. A clever mechanic and provide the stub out as needed for future work.
Good luck with your project,
Dan

Thanks Dan for the reply and ref to the FHA filter--I'll check those out. (BTW I bought 2 mobile AustinAir units that seem to help...but the FHA spews our dogs dander all over the place. I dont know why I didnt think of that type of solution!).

>>If you can install the pipe and plates your self you may be able to find a contractor to connect the boiler and fine tune the system saving a fair sum of cash.

Im really excited about doing this work. I did almost all the work on a previous remodel and my tools are feeling neglected. FWIW the staple up job would be below subfloor and 3/4" oak hardwood. I have about 1000 nails sticking down that need to clipped or grinded off first :(

>>As to the in floor, your numbers are about right

Incidentally I got a rough quote for materials from Radiantec; I didnt realize you work for BlueRidge whose website I've visited as well: I'll poke around your site again. After a 15 minute chat on the phone they came up with 36.5K BTU/Hr required for the floor (producing 43,750 BTU/Hr output). In total: 7 circuits of 300Ft PEX, 900 aluminum plates, with manifold, pump, and adapters/couplings, 130* fluid temp with 5.25GPM flow rate. (We set our Rinnai at 125* max.)

Can your company calculate a heat load without visiting the premises? (Your site says heat loss and pipe layout is $.40 is that right??) Im currently measuring all windows, walls, etc and am trying to get DWG's of the plans. I also have 2 years worth of kWh and Therm consumption data, temperature, water flow for all fixtures, and cold water supply temps (yes, Im a geek...).

>>If your satisfied with the Rinnai...

My gut is telling me I should size the mod-con boiler (plus indirect tank) to handle DHW and the floor...even if I keep the Rinnai for the short term. The problem I'm having is figuring out if (for example) the Triangle Tube Solo 60 plus the SMART 30 or 40 will be enough juice for everything.

FWIW: The Rinnai handles our demand now but I think the short demand cycles (washing hands and the like) kill it's potential efficiency. Mod-con plus indirect with proper sensors and control mechanisms just seem like such an elegant and efficient solution. I *really* want to cut my energy bills...

Thanks again and very best regards--

PP

Ack--sorry one more question:

Should I be concerned about thermal expansion of the hardwood floors? Really dont want any buckling in these nice floors...

thanks

PP

it's entirely possible to calculate heat loads from plans and good conversation.

It is absolutely impossible to calculate a good heat load during a 15 minute conversation unless you're doing a single room. Any number generated that fast is basically an official sounding wild guess. If it is being passed off as a real heat load calculation, I would take a rather dim view of that.

Thanks for the reply NRT.Rob--

I agree that it was a WAG and I don't believe they'd stand by that as a real head load calc. I downloaded a trial of RadiantWorks Pro and spent at least a day measuring windows, rooms, ceilings, etc. I have no experience calculating heat load and imagine a pro could do it much more efficiently and accurately. I dont even trust my numbers--but at least they were based upon dimensions of the house.

Without access to plans or a visit to the home I cant believe the number they gave me is even close. In his defense I didnt have a floor plan or any other info he asked for that I could send him. But if Im going to drop some serious $$ on this project I want to start from some solid data and observations.

Any comment about thermal expansion of the hardwood floors?

thx--PP

existing wood floor will likely have no real additional issues if you add radiant. most issues are moisture related. though high temp systems are more problematic than low temp systems.