Hydronic under hardsurface only?

Gooch

My family just built our house and are contemplating installing hydronic radiant underfloor heat for the upstairs, this would be done with extruded alum. c-channel transfer plates. The basement has hydronic radiant infloor heat in the slab. The upstairs is currently heated with a hot water coil inside an air handler. I understand for design purposes that a heat loss calc. needs to be done. the flooring on the main floor is probably 900sq ft of 3/4 solid oak, 250 sq ft of porcelain tile, and 500sq ft of padded carpet. my question at this point is if it would be worth putting the plates and tubing under the carpeted rooms due to the higher r-value of the pad and carpet? Or would I be ok to skip the carpeted rooms to shave some costs off the project?

Gordy

So what you are telling us is the areas in question are already covered by hydro air which is able to handle the load?

If the hydro air is covering the load you are looking for floor warming verses covering the actual load. I would do hard floor areas only.

Gooch

Yes that is correct. My intent would be for the floor heating to be primary source for those areas. Also what should my realistic expectations be for this compared to the basement with it in the slab?

Zman

Some of this is personal preference. In my mind, having 100% radiant would be worth the extra work. It is just so nice to not have the wind and noise.

As far as what will work, all of it should work. It does take some time to get all the calcs right. Radiant will work work well with most any floor when properly designed.

I am guessing you have a 2 temp system now? More details would help.

STEVEusaPA

I have extruded plates, underfloor serving hardwood, and carpeted areas. Works fine. Keep the carpet loops separate so you can control flow and water temperatures (probably need to be higher)

Gooch

Zman said:

Some of this is personal preference. In my mind, having 100% radiant would be worth the extra work. It is just so nice to not have the wind and noise.

As far as what will work, all of it should work. It does take some time to get all the calcs right. Radiant will work work well with most any floor when properly designed.

I am guessing you have a 2 temp system now? More details would help.

I do have a 2 temp system, My boiler supplys hot water to my basement slab at 100*F, My Hydro Air coil at 170*F, and my Indirect Water heater at 170*. I have an HTP wall hung boiler(80k BTU), it has 2 heating outputs(CH and DHW).

My understanding is that this type of boiler is more efficient at lower water temps so switching the main floor to radiant should make the system more efficient correct?

My biggest hold back on doing the change is the cost of the heat transfer plates, the whole area of the house main floor would require about 500 4' long plates at around $6/plate. Just trying to justify the cost beyond comfort.

Zman

I hear what you are saying. It is unlikely there is enough savings in energy to offset the costs.
It's 10 degrees out right now and I just put my cold wet feet on my nice warm floors. I really think you should do radiant throughout.

Gordy

lol I just sold my radiant castle. Doing condo for a year see how we like it. Condo on a slab with forced air...miss my floors, and ceilings already....

STEVEusaPA

The main comfort for me, and it's subtle to others, is no air movement. You never feel a draft. And a warm floor, especially in the bathroom, makes for a very happy wife.
OP, which plates are you looking at? They're are different types at different price points.

Gooch

From my research the only plates that seem worth the effort are the extruded aluminum ones like the Upon or plates.

Gordy

In light of your goals (cost). I stand by my recommendation to only do the hard surfaces which have less r value, and would require lower AWT than the carpeted areas. Although it would not get you off the hydro air for heating the carpeted rooms.

any chance the hydro air can be zoned to the specific carpeted rooms only?

Unless you can verify that you used low r value padding, and carpet in those areas.

What is your boiler make, model, and size? I'm assuming from your statement it is a modulating condensing boiler. Is it the outdoor reset set up?

Gooch

The basement is unfinished and could easily zone the air. The carpet and pad are NOT low-r.

The boiler is a HTP wall hung unit. 80k btu. The outdoor reset is not installed due to sensor issues my contractor has had with them.

Zman

Gooch said:

The basement is unfinished and could easily zone the air. The carpet and pad are NOT low-r.



The boiler is a HTP wall hung unit. 80k btu. The outdoor reset is not installed due to sensor issues my contractor has had with them.

My experience has been that the contractors "issue" with the sensor is the time it takes to run the wire and configure it.
Outdoor reset improves comfort and saves energy.

njtommy

I would definitely look into your hydroair set up and try to turn that temp down as low as possible to drive efficiency. In my experience with hydro air the fan speed needs to be lowered when the supply water temp is lowered so you don't get cooler air coming out of your vents. It maybe something to look it. What's the brand and model number hydro air unit do you have?

As for the Radaint throughout the house you could always do it in sections to spread the cost out so it less money out of pocket at one time. I would definitely do the hard surface floors first. Happy wife happy life.

Gordy

Is it a uft ?

Gooch

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His issue with them was call backs as the sensor it self seems to fail frequently causing the boiler to throw an error and thus no heat.

Gooch

Yes it's a uft.

Gordy

Funny not a lot of that going around here. Have to check ohms when installing the sensor.

Gooch

I'm deffinantly not against putting it in