We built a SIP home with hydronic radiant heating in the moderate southern California climate.

We're having difficulty getting the floors to be warm unless the ambient temp (at the thermostat) is above 72 which it too warm.

Anyone else out there have suggestions or the same issues?


John

Please describe your system. Radiant panel, heat source, control systems?

Who designed/installed it?

Don't pay any attention to him.

You can't have warm floors unless you need heat. Here in Central CA, on the coast, we don't have wamr concrete (where warm is > 72) unless the temperatures are below 50. Your home is surely different than mine, but the fact is that if you don't need heat, your floors don't get warm, only tepid. (On the bright side, you could always open a window. I'm not kidding.)

Jeff

Excuse me?

http://www.badgerboilerservice.com/experience.html

Where you live has nothing to do with your ability to engineer effective radiant floor systems - though it may influence one's propensity to rude behavior.

SIP house in socal will likely never have warm floors. Badger can dissect your system design, but there is about a 99% chance the long and the short of it is that you do not have enough load to raise your floor temps much.

if you have a mass floor there might be consistency improvements to make but it's unlikely you're going to get *warm* floors.

Perhaps carpeting or rugs - just to make it feel better on the feet.

How your floors are heated has little (if anything) to do with how the floors emit heat into the building. The radiation of floors into a heated space is a function only of three things: the temperature of the floor (the temperature at the "top" of the carpet, or the "top" of the wood floor, or the surface of the concrete), the temperature of the surroundings, and the emissivity of the materials of which the floor is made. It has nothing to do with how the floor is heated - whether you use 90 degree water or 120 degree water, a 73 degree (average teperature) concrete floor emits about 10 BTU's / square foot into a 68 degree building.

Not everything "falls apart with a non-professional design."

Jeff

mass has an effect when you are oscillating into and out of heating conditions like you do in mild climates. If his problem is that his floors don't warm up until after he goes to bed because he had no heat demands all day, reset water temps (slow recovery), and high mass floors (slow recovery), then floor sensor settings, WWSD settings or the like could improve the situation.

Seasons greetings all,
questions I have
what is delivered water temp?
out door sensor with modulation?
Condensing boiler?
Programmable T stats?
Good news is you have what sounds like an efficient home, low fuel bills
Dan

No offence Rob, but I think that you are in left field. The temperature swings here in CA are not any different than the teperature swings anywhere else - we have 10-20 degree nighttime differentials - just like you do - and we can have larger weather differentials - just like you do. We are just warmer. If anything, John's swings in Orange county are smaller than ours are.

You professionals are forgetting Occam's razor - the first place to investigate is always the one explained by the simplest set of facts. John has a (presumably) well insulated SIP house and floors that are not warm unless he turns up his thermostat. He did not state that his temperatures swing wildly, or that his heating system occasionally overheats or underheats his house. All of those statements are really big, really expressive clues that are easy matters of observation.

Jeff

Whereas floor temperature and output are directly related "warm" is a relative term. The absence of cold is a more accurate description of how well a radiant floor is working.

As heat is not lost in a linear fashion design water temperature has "everything" to do with comfort and output.

Naturally if there is no load there is no heat.

Anticipating the answer might get you "ahead" but hardly serves.

Perhaps some input from the hapless homeowner and less "WE ARE DIY"?

The radiation of floors into a heated space is a function only of three things:

Don't forget that about 1/2 of the heat transfer is via convection. But I doubt that there is much opportunity to decrease this.

Jbaron, the thing that is different is that in mild climates, your daily swings cross the threshold of need heat/don't need heat much more often than, say, here in maine. So if your system is off all day, the slab can lose a lot of its charged heat and cause a delay in heat resumption... a lag.

Here in maine, I'm not going to cross the 'no heat needed threshold' again for any significant time until april sometime. it's a non issue in that case. but I see issues with mass floors in mild climates occasionally due to the intermittent nature of the heat demands. IF that were the cause of the problem it could be rectified. much more likely, of course, is just that the heat load is tiny and so the floors aren't that warm.

John in the OC

I live in a sip home with radiant floors. Mine are concrete. My floors only get warm when there is a call for heat. That only usually happens when the outside temp gets down below 50 degrees.

We like warm floors in the morning, so we would tweak the settings so that the system calls for heat an hour or so before we get up.

Installed by our contractor designed by; Bkue Ridge un Wash.

Opps  cannot cut and paste int his forum    Blue Ridge Mountain

"Don't forget that about 1/2 of the heat transfer is via convection."

The P.E. Phds. over at ASHRAE disagree: "Low temperature radiant panels in buildings emit almost all of their energy in the infrared region."

Convection is directly related to surface temperature and is not linear.

Solar gain can through off any model in nearly any climate.

Controls are the answer to optimizing comfort and fuel efficiency.


Perhaps you should stick to your knitting and leave the design questions to we professionals?

Thanks for all the tips...think I'll start with a timer control early am then off in a few hours.


What does "WWSD" stand for?  Ideal Boiler temp should be 60 degrees (C)?

Warm Weather Shut Down,

There is no ideal boiler temperature.

Outdoor reset will improve every radiant application improving fuel efficiency and comfort at once.

Nearly all condensing boilers include this feature which is unfortunately not universally known or applied when available.

The Thermostats are LuxPro (1 seems defective) the boiler is a Laars Mascot HT1.330 and reseve tank