Down to the nitty gritty - here is what it cost
Radiant Slab System Total 1,405.80

Type IV 1inch insul R5 under slab 530.05
Tape for Foam 33.18
Pex for Slab 1500 ft 1/2inch zurn oxybarrier 619.98
Clips 0.29 44 12.76
Pex Tools cutter and crimper tool 80.85
Plastic Cable ties 19.03
Penetration els 19.31
Pressure test kit, gauge, fittings. etc 50.28
Foam, Glue/Caulk for Insul 33.48
Misc Pex fittings 6.88

Manifold for PEX Radiant Total $1804.50

Zurn brass manifold modular system 416.90
Manifold Brkts 31.99
Taco switching relay & White Rodgers Prog Therm 178.70
Therm wire & grommets 3.91
Radiant side pump Taco 00R-MSF1-4IFC 76.20
3/4 Flange Ball Valves 2 39.98
Vertex side pump,flanges Brass Grundfos
UP15-10BUC7 225.27
Switch, box and cover 2.47
Heat Exchanger & Mounting bracket 5X12 30Plate 205.95
Valves, fittings 310.45
Gate Valves for supply side 45.62
Temp Guage (2) 49.98
Expansion tank #30 34.99
Air Separator 99.99
3/4 Copper tubing 30 ft 77.00
Pipe dope 3.17
Gatorbite removal tool 1.93

Heating & Domestic Hot H2O Sys Total 2583.79

Propane 50gal Vertex 100 LP GDHE 50 LP 2118.00
Pex and Ts 26.82
PVC and els for vent 20.53
Shut offs 3/4&Fittings 26.74
Drain 1.10
Install 320.00
System Isolation shut offs 19.03
Pressure tank & fittings 51.57

Total $5794.09

Prices include shipping and tax. I had the hot water heater installed by a professional since it was propane fired. I probably could have just as easily done it myself and saved the $320 installation fee, but I had no way to cut the holes in the wall for the direct vent without buying more tools I would likely not need again, and I was not confident in my ability to get all the fittings tight enough so they did not leak. The same crew installed the rest of the propane lines in the house for an additional $100. I had the propane line system laid out and ready to put together.

I did not necessarily use all the materials priced out in each category, for example I still have several feet of 3/4 copper tubing, but the way I am tracking my house costs, each item gets put where it was purchased for, though it might end up having some used in other locations.

Other than the hot water heater install, the rest of the labor was my own so no charge. Hope this info is helpful in helping others figure out costs.

-Rosalinda

"Prices include shipping and tax. I had the hot water heater installed by a professional since it was propane fired."

I feel better now and you have a factory warranty on an expensive piece of equipment.

you should add a variable speed injection control. cheap way to get nice reset control over the system.

Just had the house energy rated/tested by my evaluator for eStar and NYSERDA, and the NYSERDA inspector Bret, came along also, and brought his infrared camera. Bret is a radiant and geothermal heating contractor and he was very impressed with the entire radiant system. All the loops in the floor look great and are heating evenly. Bret said he was very impressed with the design and installation and that it was a better executed than most of the professional contractor jobs he has seen.

The hot water heater tested at just under 98% efficiency which is great - vent exhaust temp of under 40 degrees.

-Rosalinda

Cheap injection?

How does a heat source exhaust get below supply water temperature? that must be during a domestic demand?

I considering adding a reset control to this config cheap since it doesn't require any additional components.. the pumps are already present and ready for operation. makes going reset pretty cheap. especially if it drops any other form of temperature control like a tempering valve or what have you.

Right now my incoming water temp is 39 degrees from the spring on my farm, but this was radiant demand only, no domestic being used at the time of the test. The water heater has its own air source so would that contribute to the cooler exhaust? It was in the low 30s outside at the time of the test.

The injection controls I looked at were in the $500 range. Can you explain how this works and where it goes and what it is supposed to do? I am not using a tempering valve and so far don't see a need for one.

Thanks,
Rosalinda

we use the tekmar 356. it runs the water heater pump at variable speed to modulate the radiant temp, which makes the floor more consistently conditioned. can help prevent overshoots too.

your incoming water temp shouldn't matter for a radiant demand.

As far as I know, exhaust should always be at least as hot as what you're heating.... but I'm no water heater expert.

Posted By Rosalinda on 23 Mar 2011 12:52 PM
Just had the house energy rated/tested by my evaluator for eStar and NYSERDA, and the NYSERDA inspector Jeff, came along also, and brought his infrared camera. Bret is a radiant and geothermal heating contractor and he was very impressed with the entire radiant system. All the loops in the floor look great and are heating evenly. Bret said he was very impressed with the design and installation and that it was a better executed than most of the professional contractor jobs he has seen.

The hot water heater tested at just under 98% efficiency which is great - vent exhaust temp of under 40 degrees.

-Rosalinda

The  mfg. specifications for the Vertex is only 96% thermal efficiency. The testing of your appliance is more than likely not accurate. Do not confuse thermal efficiency with combustion efficiency, they are not the same. Need more information to determine the validity of your statement.

Agreed, unless you are using a heat pump on the exhaust, mixing in some other air or otherwise cooling the exhaust, the exhaust temp has to be more than the water temperature.

Any actual data on the advantage of outdoor reset where one isn't varying the water temperature within the boiler/heater?

The testing was done by experienced Energy Star and NYSERDA evaluators using all their high tech testing gear, so I think I can feel comfortable with their result. I don't have the written report yet, just what they told me and showed me as they worked. I am not confusing any kind of efficiency but am assuming they tested combustion efficiency - but will also know more once I get the written report. They had lots of gear they used to look at all kinds of things, in addition to the camera.

By the way NRT Rob, they did test how well the Panasonic ventilation fan I have in the downstairs utility room moved air from the rooms upstairs. I was doing something else at the time so did not get the details of the results, but they both seemed pleased with the adequacy of the system to remove excess humidity and pollutants.

I realized today that I actually had 2 waste pipes to the septic tank open, where the plumbing is not finished because the fixtures are not yet in. (nothing has gone into the septic tank so far but a few loads of grey water from the washing machine). I wonder if that gave me a higher ACH50 number than it would have if I had capped them, as I did with all the other unfinished fixtures. Amazing that no matter how many times I went around sealing up stuff, I didn't even think of those 2. They even mentioned about no water in the traps, but I assured them there was nothing in the septic tank yet to generate problematic fumes.

-Rosalinda

The Vertex is designed to circulate the flue gases back down through a coil in the hot water heater to extract as much as the heat out as possible before venting BUT it is conceivable that temp was C not F.

-Rosalinda