Snow Melt help NY Area

jareknyc

Hey guys I have 1250sq ft driveway in long island, doing snow melt there, I put aluminum bubble first then metal mesh, i Did 3/4 pex 350-400 feet max, spaced 11-12 inches, do you guys think that will be enough or i should put another loop in between, some sites saying its good some saying 8 inches i dont know anymore, please help...

Ironman

12" spacing is normal for 3/4" tubing. 8" spacing is normally used with 1/2" tubing because it has a smaller bend radius.

300 - 400' loop length is fine for 3/4" tube.

The real question is: was there a proper design and calculation done for your SIM system? Proper design is the FIRST step. Without that, there's no telling if it will perform properly. It's like shooting skeet blindfolded: you may get lucky and hit something, but probably not.

Bubble wrap is better than nothing, but it has no real insulation value. 1" blue board should have been used.

You haven't provided enough info about the entire system to be able to tell if it will work right.

jonny88

Any edge insulation,these systems should be designed hit up @Rich and see what he says.Rich Mc Grath.
R

jareknyc

jareknyc

I have whole house radiant heat over 20 loops in the house 1/2 used, works great for now, its a new house designed by radiant company, so i am sure it will be ok, will the driveway be ok ? will see i guess, the pic are above, i have WBV-03-WPCL Boiler now, works great with 3 zones, one is water for domestic, 2nd is first floor, 3rd circulator is 2 fl, 17 thermostats, little over 20 loops, some zones because of the room size have 3 loops...

jareknyc

Another thing i forgot to mention i will be putting pavers on top of the concrete

jareknyc

Now i am wondering what Indirect Water Heaters should i get for this project...my driveway will have 6 loops 350 max rest around 200 feet at 3/4 pex size

jareknyc

This is my current system in the basement planning to use same circulatory for my zone for snow melt and same circulator for indirect tank

hot_rod

Expectations? How quickly do you want the snow to disappear, and how much energy do you want or have to throw at it?

You can melt with 80 btu/ square foot, and in critical applications you could see systems supplying over 250 btu/ square foot

Will you start the system ahead of a snowfall? Some systems idle, some use sensors to start the system as the sensor detects snow fall.

Is some striping acceptable at heavy load conditions? These are all questions that would help decide how to design and install the system.

Or it could be based on how much boiler power you have, or plan on supplying.

In any case it will be a considerable amount of energy required to heat the great outdoors, maybe 10 times what is required to heat a home of the same dimension

Ironman

17 thermostats?? Say it ain't so. Your gonna short cycle the boiler to death.

Zman

Do you have a total system design you could post? There is a method to determine sizing. It's not just a "rule of thumb" thing.

Bubble insulation will not provide any insulation value. If the tubes are placed at the bottom of the concrete with pavers at the top, your snowmelt performance will suffer (the worms will be happy). Heat does not rise, it radiates. You need proper tube placement and significant insulation to direct it upwards.

I agree with Bob's concern about the zones. I would recommend either combining zones or installing a buffer tank.

jareknyc

Yeah i already purchased tekmar ice snow sensor and tekmar thermostat that will be on, Ironman I love that idea, the system is so nice with 17 thermostats its crazy, tekmar controls all of the zones and temperatures, boiler is almost neven on, and temp inside the house is 70 at all times, if i wouldnt do all this zones my pantry would be 80 and my master 72 and my big tv room would be 65 becacse I have one thermostat...now since every zone is controlled individually with actual floor temp sensor and ambient temp, the system is sick, if you have money to spend on that you should do it, its best thing ever!!

jareknyc

Zman said:

Do you have a total system design you could post? There is a method to determine sizing. It's not just a "rule of thumb" thing.

Bubble insulation will not provide any insulation value. If the tubes are placed at the bottom of the concrete with pavers at the top, your snowmelt performance will suffer (the worms will be happy). Heat does not rise, it radiates. You need proper tube placement and significant insulation to direct it upwards.

I agree with Bob's concern about the zones. I would recommend either combining zones or installing a buffer tank.

The only think I have is what i took pic of, 3 zones one 2fl one 1fl and one water heater, 2 floor has 7 zones, 1 floor like 10...(zones i mean loops controlled by thermostat)

I gave you guys the model number of the boiler, temp there is set at 135 high 110 low when no heat is being called, works great almost never on...used 25% of oil since march,

jareknyc

hot rod said:

Expectations? How quickly do you want the snow to disappear, and how much energy do you want or have to throw at it?

You can melt with 80 btu/ square foot, and in critical applications you could see systems supplying over 250 btu/ square foot

Will you start the system ahead of a snowfall? Some systems idle, some use sensors to start the system as the sensor detects snow fall.

Is some striping acceptable at heavy load conditions? These are all questions that would help decide how to design and install the system.

Or it could be based on how much boiler power you have, or plan on supplying.

In any case it will be a considerable amount of energy required to heat the great outdoors, maybe 10 times what is required to heat a home of the same dimension

I was thinking tt-40 water tank and this two circulatorsm, one from boiler one to the manfiold, than play by ear with temp, start at 100 F

I dont know what I should do anymore, I have double sided bubble wrap I heard its good, now someone mention that might not be enough... I am lost now

jareknyc

also my whole house is made with boards with foil and works great...dont tell me they did it all wrong

Brewbeer

How did your house system perform during the valentine's day weekend article air oubreak last February? That was the coldest it's been in the past 20 years. Did the house stay warm?

Zman

Not sure what type of insulation boards they used in your house. Usually the panels with reflective coating have a real r-value and are combined with another type of insulation like fiberglass.
Here is just one article on why bubble insulation under radiant slabs is nonsense. http://www.pmmag.com/articles/89247-bad-science-br-john-siegenthaler-pe
There are plenty more if you do a search.

I am glad that your existing system is heating your house comfortably, it really seams excessively complex to me. If the original installer had done a room by room heat loss and altered the tubing spacing based on the heat loss for each space, you could get the same balance you have now without all the zones.

If your boiler fires and the on cycle does not last long enough to burn the acidic condensate out of the flue, your over zoning is damaging your boiler.

Without getting too far into it, you can safely assume that your driveway will need at least 100 BTU/hr/ft in order to melt snow, that is 125,000 BTU/hr. This number will likely be higher given the lack of insulation and the pavers. How are you planning to accomplish this with a ~100,000 BTU/hr boiler? Not to mention the house heat and the domestic hot water.
Low boiler return temps and condensation also become concerns in this scenario.

I think you need someone capable of doing the math to help you with this project.

Ironman

jareknyc said:

Zman said:

Do you have a total system design you could post? There is a method to determine sizing. It's not just a "rule of thumb" thing.

Bubble insulation will not provide any insulation value. If the tubes are placed at the bottom of the concrete with pavers at the top, your snowmelt performance will suffer (the worms will be happy). Heat does not rise, it radiates. You need proper tube placement and significant insulation to direct it upwards.

I agree with Bob's concern about the zones. I would recommend either combining zones or installing a buffer tank.

I gave you guys the model number of the boiler, temp there is set at 135 high 110 low when no heat is being called, works great almost never on...used 25% of oil since march,

If you're running the boiler below 150* without return water temp protection, then the flue gasses are gonna condensate and that will ruin the flue and boiler:

''When the return temperature from the system will be below 150°F on oil boilers for extended periods (heat pump systems, outdoor reset, snow melt, etc.), provide piping and controls to protect the boiler from condensation. Condensation will damage the boiler and will lead to shortened boiler life and maintenance problems." - from your boiler's installation manual.

jareknyc

Well bubble wrap might not be enough I went to Lowe's just now and they have this foam boards, I guess I will buy them and put it underneath the Buble wrap? Is that correct? That should help insulate ?
Yeah that 135 140 setting is done by the installer it works well...after 6 months no problem yet...also in New York area we might have snow 10 times might only use it 10-15 times per year...I just don't want to invest all that money and not melt anything...can anyone help here please ?

hot_rod

you will need a boiler dedicated to the snowmelt system. Typically when you are melting snow you are also heating your home, so you would have little excess energy from the boiler to send to the snowmelt. If oil is the only option it will require some boiler temperature mixers and low return temperature protection.

Ironman

jareknyc said:

Well bubble wrap might not be enough I went to Lowe's just now and they have this foam boards, I guess I will buy them and put it underneath the Buble wrap? Is that correct? That should help insulate ?

Yeah that 135 140 setting is done by the installer it works well...after 6 months no problem yet...also in New York area we might have snow 10 times might only use it 10-15 times per year...I just don't want to invest all that money and not melt anything...can anyone help here please ?

You're saying it's okay looking at the outside of the boiler, not inside. Several Pros and the manufacturer are telling you that your boiler won't last long without return water temp protection.

We ARE trying to help, but it appears what we're saying is going unheeded.

SWEI

Sure looks like bubble wrap under the rebar. That's going to be really tough to heat.

jareknyc

Yes I will have temp mixer, also protection for the boiler temp lower than 80 degrees will never get back to the boiler

jareknyc

I was thinking to maintain 100 degrees at all times in winter in the dedicated indirect water heater for snow melt...you guys think that will be enough? Also I agree the bubble wrap it's not enough...by putting this boards that I have pictures above underneath the bubble wrap will it help my case? I would hate to throw it out it was expansive stuff

SWEI

That's likely 25 PSI foam, possibly even less. You may need XPS foam depending on the soil moisture levels. In those quantities it should be less expensive from a foam supplier -- and you will have a full range of options for size, thickness, and density.

Foil does nothing below grade, BTW.

jareknyc

I have 10 inches of rca under there almost no soil left,

jareknyc

I can't add to much to this anymore, if I add 4 inches I will have liken 1 inch left for concrete, other wise my pavarers will be higher than my garage door

jareknyc

So 1/2 inch xps would improve my install ? If I put that under that bubble wrap?

jareknyc

Ironman said:

jareknyc said:

Well bubble wrap might not be enough I went to Lowe's just now and they have this foam boards, I guess I will buy them and put it underneath the Buble wrap? Is that correct? That should help insulate ?

Yeah that 135 140 setting is done by the installer it works well...after 6 months no problem yet...also in New York area we might have snow 10 times might only use it 10-15 times per year...I just don't want to invest all that money and not melt anything...can anyone help here please ?

You're saying it's okay looking at the outside of the boiler, not inside. Several Pros and the manufacturer are telling you that your boiler won't last long without return water temp protection.

We ARE trying to help, but it appears what we're saying is going unheeded.

All I said that I didn't modified anything what the builder did (experience hvac guy)
OK I understand Bob when I will add the loop to the snow melt to add low temp protection, and I will, I appreciate that pointer

Ironman

jareknyc said:

Ironman said:

jareknyc said:

Well bubble wrap might not be enough I went to Lowe's just now and they have this foam boards, I guess I will buy them and put it underneath the Buble wrap? Is that correct? That should help insulate ?

Yeah that 135 140 setting is done by the installer it works well...after 6 months no problem yet...also in New York area we might have snow 10 times might only use it 10-15 times per year...I just don't want to invest all that money and not melt anything...can anyone help here please ?

You're saying it's okay looking at the outside of the boiler, not inside. Several Pros and the manufacturer are telling you that your boiler won't last long without return water temp protection.

We ARE trying to help, but it appears what we're saying is going unheeded.

All I said that I didn't modified anything what the builder did (experience hvac guy)
OK I understand Bob when I will add the loop to the snow melt to add low temp protection, and I will, I appreciate that pointer

No, it's not just needed for the SIM. The temps that you're now running are too low for the boiler. As per manufacturer's instructions, they must be above 150*.

jareknyc

Ironman said:

jareknyc said:

Ironman said:

jareknyc said:

Well bubble wrap might not be enough I went to Lowe's just now and they have this foam boards, I guess I will buy them and put it underneath the Buble wrap? Is that correct? That should help insulate ?

Yeah that 135 140 setting is done by the installer it works well...after 6 months no problem yet...also in New York area we might have snow 10 times might only use it 10-15 times per year...I just don't want to invest all that money and not melt anything...can anyone help here please ?

You're saying it's okay looking at the outside of the boiler, not inside. Several Pros and the manufacturer are telling you that your boiler won't last long without return water temp protection.

We ARE trying to help, but it appears what we're saying is going unheeded.

All I said that I didn't modified anything what the builder did (experience hvac guy)
OK I understand Bob when I will add the loop to the snow melt to add low temp protection, and I will, I appreciate that pointer

No, it's not just needed for the SIM. The temps that you're now running are too low for the boiler. As per manufacturer's instructions, they must be above 150*.

so what you saying is I should set my boiler at 150 now just for domestic water now?

jareknyc

Ironman I have couple questions for you about the setup, since I already put the bubble wrap and I wasted money there, you think I should just leave that there and try to put that 1 inch board under the bubble wrap? is that the stuff I sent the picture of from lowes? I tried to find ideal temp in the manual for my boiler and I could not find anything about 150 degrees, but since I will be using it in winter now much more I will leave it at 150...I will wait for your response but I will also put insulation on the corners since I think someone mention that...

Ironman

I'd go to a real building or insulation supply and get 1" blue styrofoam board. Tell them it's for insulating under a slab. Lowes may have it, but their employees may not know what you want. Just put it on top of the bubble wrap.

The boiler needs to maintain 150* min for any application so your flue gasses won't condense and rot the boiler, flue, and chimney. The "ideal temperature" going out to any application can only be determined by proper calculations; there is no set temp that works for everything. The boiler will have to run at a higher temp than what the radiant floor requires; that's why a mixing control is needed. If you had a gas fired mod/con boiler, things would be different, but an atmospheric cast iron boiler must be run at a temp that is hot enough to keep the flue gasses above due point.

jareknyc

Ironman said:

I'd go to a real building or insulation supply and get 1" blue styrofoam board. Tell them it's for insulating under a slab. Lowes may have it, but their employees may not know what you want. Just put it on top of the bubble wrap.

The boiler needs to maintain 150* min for any application so your flue gasses won't condense and rot the boiler, flue, and chimney. The "ideal temperature" going out to any application can only be determined by proper calculations; there is no set temp that works for everything. The boiler will have to run at a higher temp than what the radiant floor requires; that's why a mixing control is needed. If you had a gas fired mod/con boiler, things would be different, but an atmospheric cast iron boiler must be run at a temp that is hot enough to keep the flue gasses above due point.

Yes in my system I have to mixing valves right now one is for 2fl and other is for 1 fl...since the high will be set at 150 what would be the low and stanby be?

jareknyc

I will do this boards Monday, the spacing about 11-12 inches pex 3/4 is fine? also I was thinking to put one loop by the door where you have the first step could I use 1/2 pex there since its small pex ? or go with 3/4?

kcopp

You Need to stop and take a deep breath....

Start from the beginning and get some design help before you do anything else....period.

There are plenty of good design folks who can help you. try the find a contractor link at the top of the page.

jareknyc

kcopp said:

You Need to stop and take a deep breath....

Start from the beginning and get some design help before you do anything else....period.

There are plenty of good design folks who can help you. try the find a contractor link at the top of the page.

nothing in my area except one 45 miles away, I will pass on him since he is doing only heating boilers, all I need is couple pointers, I did my radiant in the basement and garage and it works great, I have HVAC guy who will come and get everything connected for me, just trying to do this pex outside before winter comes, I want them to come already and pour concrete and do my pavers...we all know its not crazy it takes one person with some good knowledge and willingness to help and share info, I will adjust what I did already to make it the most efficient I can...In the near future anyway i will be switching to gas since city is planning to put gas around the corner...All i am doing is trying to make this system work if I can, I will be using it probably 5 times per year that's it...Trust me had guys walking and telling me 25 different stories no one seam to have experience when comes to radiant in my area, especially outside

SWEI

Design work can be done remotely. We have a number of members here who are well-qualified and do just that. Spend a few bucks and find out what you need before you pour the concrete.

ratio

You only get one chance to do it right, before the concrete goes down. There are, however, lots of chances to chisel it up & do it again. Use the find a contractor link to find someone who can help you.

Gordy

Nothing would be more disappointing than lighting off your snow melt, and following it up with a shovel, or snowblower..............

Tinman

I could come up with a thousand cliches for this but I'm going with this - "A thing worth doing, is worth doing well." Or something like that.