New House Q's

Tim Potter

Hi, I just bought a house at Winter Park Colorado ski area.

The House is 10 yrs old, 1700sq' heated, well built, & highly insulated

I have some concerns about the radiant heating.

I have a 150,000 btu slalant-fin SX-150EDP boiler in the lower level

As best as I can tell my zones are as follows:

2 zones of radiant in floor lower level (Daylight Basement Living area).

Lower zone 1 = 450'sq carpet and tile on slab.

Lower zone 2 = 250'sq carpet and tile on slab.

Upstairs on main floor 2 zones of underfloor radiant.

Upper Zone 3 = Tile floor in Kitchen, Foyer, & Dining. Carpet in LR 700 sq'

Uptairs zone 4 = Tile in 2 bathrooms, and carpet in bedroom, 300 sq'.

Zone 5 = 250 sq' slab Garage.

Zone 6 = 80gal Amtrol Boiler mate WHS80.



OUR SETUP IS:

BOILER, to air sep/exp tank, to grundfos 26-99, to 6 shot manifold, to 6 load,s back through 6 zone valves, to 6 shot manifold, to old pump that does not work, finally back to BOILER



My concern is I don't see any Boiler return protection, and all zones run at the same temp, UnderFloor, In slabs & DHW.



I also would like to monitor and control temps remotly - ie through the internet we have installed, (but No Phone)

 

Would you run Pri/Sec with Boiler temp through the DHW, slightly cooler on the under floor, and cooler yet for the in slab?

 

I have  Dan's book, "Primary/Secondary made easy" and I understand it, I just don't know if this setup is right.



Thank You for your advice



Tim

Tim Potter

Here is a Pic

Here is a pic of what I Have



Thank You:

Tim

Mark Eatherton

Does not sound right to me....

I think you are on the right path, but it is going to require a major work over of your system.



Your current boilers output is probably 2 times greater than your needs. It's output is 46 btu/square foot per hour. If your home is truly a super insulated home, then your needs are around 15 to 20 btu's per square foot.



You can put band-aids on it (proper mixing valves, etc) but it is still grossly oversized, can't modulate to real time loads, and will most probably short cycle itself to the grave.



Consider replacing the whole shebang with a newer modulating/condensing boiler, and reduce your energy consumption by 30%.



ME

Tim Potter

First step?

Mark,

Thank You for the reply.

I can't afford to blow it all out and start over.

I can start to rebuild the system, with a future modulating/condensing boiler replacement, and Boiler/system control installation in mind

If you were going to break this down into steps, what would you suggest?

Tim

Mark Eatherton

Well.....

That is a loaded question. You're going to have to reverse engineer the whole system, starting with a room by room/zone by zone heat loss calculation. I assume you have not lived there for a Winter yet, so you are still in the "discovery" stages.



Then, you will need do some some exploratory sheetrock surgery to determine what method was used to deliver heat to the radiant floors above the basement. While you're at that task, make note of the type and thickness and application of insulation in the joist bays. While you are at it, find out the brand name and type of tubing used.



Then, you will need to do a piping zone check and determine what supplies are matched to what returns, and what areas are served by those pipes.



Then, you can begin re-designing the boiler side of the system. It will require the addition of a pump, and a mixing valve to serve the needs of the tube in concrete zone, and possibly some of the under floor zones as well, depending upon how they were installed.



You will then have to re-pipe the boiler in a primary/secondary manner, and pipe the DHW storage tank as a parallel circuit to the boiler circuit.



In this process, you will need to modify the controls to separate the low temp calls, from the medium temp calls, from the high (if necessary) temp calls.



In any case, during a call for space heat, the return water should not be allowed to drop below 140 degrees F, hence the need for a modified control logic. Alternatively, you could install a thermostatic protection device, but it would be thrown away once you convert to a mod con boiler.



None of these efforts are going to eliminate the short cycling that your system will experience, but at least when it comes time to convert the boiler to a modulating high efficiency unit, you won't be wasting a lot of components.



The above work is not for the faint hearted. Make certain the contractor you choose knows what he is doing. A lot of guys can talk the talk, but when it comes to walking the walk, they lose it.



In the interim, keep an eye on your flue pipe. That is usually the first component to fail due to condensation production. also, have your boilers fire side serviced by a competent service contractor, and get yourself some CO detectors and place them throughout the house.



The pump may just be stuck from sitting over the Summer. Make sure the power is off. There is a large cap screw on the end of the pump. If you remove that, you will have direct access to the rotor of the pump. If you can spin it, and it starts working OK, then you are done. If it spins freely, and you have verified the presence of electricity going to the pump, it is dead and needs replaced.



You have a lot of work ahead of you to get it straightened out...



ME

Tim Potter

Replace Boiler...

Again Mark, much to do and great thinking points for when I get out there Sat.

What kind of boiler would you put in?

Wall mount Mod/Con Triangle Tube, This photo is from a current project the builder (who built our house 10 years ago) is completing now.

Or something like the rAy cast iron condensing boiler.

I am wondering if the original plumber may have sized the boiler to run the DHW tank instead of the house.

It is awfully nice to come home from a day of skiing to everyone taking a nice hot shower.

I suppose the modern modulating boilers would have the power to heat large amounts of water in a short time and throttle down to manageable levels for heating

The things I think are important are: (please edit and rearrange as needed)

1) Protect the in slab radiant from High Temp Feed Water (max 120?)  

2) Protect the main floor radiant from High Temp feed water (max 150?)

3) Protect the present boiler from low temp return water (135 or greater)

4) Remote access through the internet

5) Economy and comfort, I think with the modern boiler controls they go hand in hand.

Mark Eatherton

It's not so much the boiler that counts....

As it is the contractor who stands behind it. They've ALL got good and bad points. Make sure you're comfortable with the contractor, because you're going to have to live with HIM for the rest of your life.



Your points look in good order. Make sure you get some CO sensor/alarms in there if you don't already have them.



Probably wouldn't be a bad idea to have the combustion checked. Fouled burners are dirty burners, and that equals hi CO in the flue gas stream. All it takes is an oversized Jenn Airre grill to pull the CO throughout the whole house in minutes.



Have never used the rAy, but know one of it's developers, and he's worth his weight in gold. When he's standing behind the product, it's not a problem. Cast iron condensors are new to USA, but have been around for a lot longer than most people realize (Vitola Biferral/Vertomat??) In any case, at the right thickness, cast iron can show strength for the long term... under adverse conditions.



Sizing for DHW in a ski home IS important. And you are probably correct in that assumption. If I hadn't had my head up my colon, I would have realized that... :-) DHW loads are ALWAY greater than space heating loads in ski resort settings. Modulation would stlll be a good thing, because even that load is a variable, and driving tacks with sledge hammers is NOT a good use of energy :-)



EVERYTHING in modulation ;-) Proportional. Efficient.



Nice install on the TT's BTW.



ME

Tim Potter

Relationships... what a novel concept

Boy you are so right in the living with the contractor concept. I'm in the auto repair business, and I am always talking about developing a relationship with your service provider (no matter what kind of service) Personal relationships are so valuable on both sides of the Invoice.

Got the CO sensors - its now a law in Colorado on any sale.

As far as the Picture, I wish that guy had designed my system, we probably wouldn't be talking now... I'll find out from the builder who subcontracted for that job.

The more I think about it, the main floor tubing is probably set in gypsum, when the heat first comes on I can feel the Heat stripes in the tile floor for a while. I'll find our this weekend. I believe if that is so, then the re-plumb job becomes less complicated. 1 low temp circuit, just have to get the boiler water down to 120 max. ?

As far as managing water temps and systems, Do you add Tekmar (or others) controls, or do you use boilers with built in controls (rAy Outdoor & Indoor reset,  TT ODR) ?

It seems from reading, that the people who have Indoor reset like it a lot...

Thank You for your input on this, I am learning a lot!

Tim

Mark Eatherton

Controls...

Most of the newer class of mod cons come with their own logics on board. Indoor reset is a good thing. The outdoor reset is necessary for the basic control set up, but with indoor feedback, the outdoor reset can be suppressed, or boosted depending upon what the reaction of the home inside is. I suspect that eventually, everyone will have that as an option in their logic.



THere are actually only 2 or 3 controllers out there that all the different mod con manufacturers use, and some of them are not utilizing nearly the potential that is available from the onboard computers. Lochinvar, for the money, has opened the control up to the contractors, and it is a honey.



Viessmann is also an excellent logic, that is borderline artificial intelligence. It "learns" the home, and the system, and learns how to react accordingly. Kind of scary at times. Especially when you see it ignoring a call for heat ;-)



If in fact your tube is in Gyp, then yes, it will significantly simplify matters, but based on field experience, I would still recommend the use of a thermostatic device for controlling the return water temperature to the boiler. The solid state logics work, but not as well, and I have seen some cast iron boilers showing significant signs of corrosion form condensate, even with the S.S. controls on board.



ME

Tim Potter

Controls...

OK, wow its taken Qwest 7 days to get the DSL up, unbelievable.

So back to the house, The main floor is in Gyp, and the Tubing is Wisbo hePex 1/2". The 2 big zones are actually 2 parallel runs on 1 zone valve. it works out to be about 300 sq ft per run.

What do you think the max water temp running through the tubing should be?

What changes could/should be made now, to limit the tube water temps, while protecting the present boiler.

Primary/Secondary looks like it could limit supply temps while protecting the return temps. Then when the time comes for a new boiler, it could hook right up.

and/or:

 If I could buck up and get a new boiler, something like the TT 60K (depending on the heat load) it modulates down to 16K and would be condensing all the time for the heating, Then re-task the present boiler to fire the indirect.

and/or:

Something totally different I haven't thought about?

Again thank you for your input, I am learing so much



Tim

Jean-David Beyer

Remember, I am not a contractor.

If you plan to spring for a new mod|con boiler now to run both a radiant heating system and an indirect hot water heater, you should  consider a boiler such as the Weil McLain Ultra 3 series. These happen to be rated by the BTU/hr input. I do not insist on this brand, but it is the only one I know, since I just had one installed here last May.



The model I have is the 80K/hr one that modulates from 80K down to 16K btu/hr, and has outdoor reset. The feature I think most pertinent for your question is that it has three thermostat inputs that run priority 1, 2, and 3, with one being the highest. At each priority you set the maximum and minimum temperatures and the outdoor reset decides based on the outdoor temp where along the curve it will fire the boiler. I have the indirect hot water heater set to run at 180 at priority 1. I have my radiant slab at priority 2 set to run from 120F to 70F depending on the outdoor temp, and my Slant/Fin baseboard stuff upstairs set to run from 140F to 80F. Almost all of this is done by the control board that comes with the boiler. The one thing it does not handle is the last circulator for the upstairs, but a simple Honeywell relay box takes care of that. (the W-M control board can drive only 3 circulators, and I need 4.)



It may be that this kind of thing is available from other manufacturers, but I have not looked. It is sure convenient to have that all handled without a lot of extra stuff. If you cannot stand an aluminum heat exchanger, you will have to look elsewhere for these features.

Mark Eatherton

Supply water temps...

are dependent on the tube density (probably 12" OC in your case) and the resistance values of the finished floor goods placed over the top of the radiant surface, and the insulation placed below the heat emitter. Gut feeling is 140 MAX.



The tubing is an oxygen barrier tubing, which is a good thing.



Do the two circuits have similar floor coverings (R value wise)? If not, can the bey separately controlled?



P/S piping would address the issues at hand, but will not be necessary when you put in the modcon, so it would be money down the drain.



I guess at this point you have to ask yourself, do you really need THAT much DHW, or could you exercise a little loading flexibility (not all four people showering at the same time) and get by with the smaller package...



80K btuh at that altitude would kick out about 1 GPM of 140 degree F water. You could take endless back to back to back showers, and avoid the need for excess boiler sizing. You will probably need to use the existing B vent to vent the new boilers plastic vent, which means you can't have any other appliances dumping their byproducts into the same chase.



ME

Tim Potter

Thank You for the replys

JD, thank you for the input.

ME, had some time Fri & Sat to hunt around, something didn't add up on that big zone on the main floor, So I hunted around with a flashlight, and found  Hidden Panel in the closets.

Zone 1 has 4 hePex loops off a 3/4 copper supply line covering Kitchen/Foyer/Dining room (limestone tile) & Living room (carpet). did not have time to shut off valves to determine which loop is heating the different areas - Next Time... Good excuse to be back in CO.



Zone 2 has 2 hePex Loops off a 3/4 copper supply line covering Master BR (carpet) and Master Bath (Tile)



Zone 3 has 2 hePex loops off a 3/4 copper supply line covering Bedroom(carpet)/Bathroom (tile)/Family room (carpet). was able to determine by shutting one of the valves overnight, 3a covers BR/Bath, and 3b covers Family room. Good to know if I ever want to add an additional T-stat/Valve to isolate rooms.



Zone 4 has 1 hePex loop off a 1/2 copper supply line covering Bedroom/Bath



Zone 5 has 1 hepex loop off a 3/4 copper supply line covering single car Garage



I was able to unhook the power to the Grunfos, and the Taco 7 boiler circulator is working. I guess they added the grunfos to solve a circulation problem.



So I guess I have to figure out what I want to do...

If I keep the existing boiler, add a return water protection diverting valve (Sparcomatic MX-128?) using the Taco as a boiler circulator, add a 35/40 gal buffer tank to take care of the short cycling I am going to create by adding the return water protection, re-work the manifold/Grundfos to supply the zones out of the buffer tank, what kind of controls do you recommend to utilize the buffer tank in full reset mode? I was on Tekmars website, Is their 422 outdoor reset module, 335 zone manager with their tn4 T-stats and the 483 remote access module a good candidate to run the whole match? Seems like all the additional equipment/controls could still be used when the present boiler is replaced.



Again, thank You for your input



Tim

Mark Eatherton

Where is the double ot 7?

I looked at the photo again, and didn't see it in the picture? Is it in series with the Grundfos?



Although tekmar is a good control choice, if you go with the right mod con boiler, other than the zone controls, you wouldn't be reusing anything.



I've never used a Sparco in that application. I was thinking more of the ESBE Termovar valve like http://na.heating.danfoss.com/xxTypex/156252_MNU17421643_SIT209.html



Proven technology.



The good news/bad news about your tubing distribution patterns is that in those zones where you have big differences in surfaces (carpet vs tile), regardless of where the thermostat is, it will be in the wrong place 50% of the time...



The good news is that you could set a wireless control and wireless thermostat (Honeywell) and possibly separate those circuits serving two different zones.



ME

Tim Potter

Circulator is positioned at the boiler inlet !

The Taco is in its original factory installed position at the boiler inlet. It looks they added the Grundfo's later.



As far as controls go, I was thinking I could add a lot of controls/T-stats/Remote access and a buffer tank for less than the new boiler would cost. I could run the present unit out, and who knows what will be available then.



The reason I was wondering about the Sparco, I have one. Don't ask how a guy who fixes cars and tires for a living has one of those...



The 4 loop zone header is fairly close to the boiler room, so they could be separated if needed.



What part # wireless Honeywell were you thinking?







Thank You again



Tim

Mark Eatherton

Just goes to show ya...

The attitude of "If a little pump does a little good, a LOT of pump will do a LOT of good", and that is not always the case.The Grundfos is actually hindering the Taco at this point, and if it (007) is capable of maintaining good comfort conditions, the Gfos may not be necessary. But it was installed for some reason....Actually, if you can avoid the use of wireless T-stats, it would be better over all. You need to run an 18/6 wire for each additional zone, between the boiler and the manifold and an 18/2 from the manifold location to the thermostat location.If the Sparco does not have too high a pressure drop, it could probably be used. Set it for 140 dergees F, and if the return water comes back too low, it will close the cold port (return port) open the hot port and bring the boiler up to temp before releasing more energy into the system.I would not expect to realize much if any energy savings from throwing all the time and money you will be doing to the existing system. 80% is still 80%. You will be increasing the life expectancy of the appliance for the most part.ME

Tim Potter

Update posted in main wall

New potential design posted under main wall



Thank You for your input



Tim