First of all, I would like to thank to those who have made the existence of heatinghelp.com forum possible, and to all the members of this wonderful community for allowing me to read useful info and to post my first message here.
I hope you can help me with a retrofit project that I'm planning for my house (I live in Waterloo, Ontario, Canada). I am originary from Europe and it's suffice to say that I'm not keen to the forced air heating systems which you can commonly see here in North America. I grew up with hydronics and I'd like very much to install such system here. [I apologize in advance if my message will be too long.]
I'm thinking about using a Viessmann Vitodens condensing gas boiler (either the WB1B-26 or WB2B-19 model) and classic radiators (steel panel rads). I am not an HVAC professional (I'm only an IT guy) but I am counting on the help of my father (who is about to come here in Canada within a month). My father is a "jack of all trades", being crafty in masonry/construction, general mechanics, and even plumbing and gas. He has done more than twenty hydronic installations back in Europe.
There are a few "variables" with our new project:
-First, the hydronic systems which my father had done in Europe were mostly involving integrated systems. For example, no external pressure vessel or external recirc pumps, no hydraulic separators or closely spaced tees, not too many heating circuits - everything came integrated with the (system) boiler (which is called over there also a "central heating system/station"). Also, he was never involved in projects dealing multi-zoning and motorized control valves. But he is very good at installing a basic heating system (one primary circuit), pex-AL-pex and Copper piping, radiators, gas fitting and so on.
-Second, I have asked for several quotes from some local companies here in Canada, and the prices seemed skyrocketting and there wasn't too much flexibility in terms of rads sizing, thermostats, zoning etc. That's why we decided to go with a DYI approach. Now, because I am not a (licensed) company, I have tried IN VAIN to get some prices for individual parts such as steel rads, Viessmann boiler etc. I don't know how it is in US, but in Canada it feels like a 'cartel' and protectionist markets and simply put, no company wants to speak with me once I tell them I'm a residential customer. And paradoxically, the Viessmann Canadian headquarters are located at 3 miles from my location. Also, the main Canadian distributor for Biasi / Quinn radiators is in nearby (60 km). None of them wishes to do business with me directly. I am telling you this because this is a factor which will influence A LOT the cost figures for the project - since I'll be forced to buy via some US located stores, eventually online - i.e. www.eComfort.com.
Now, please allow me to indicate Manual J calculation results. I have used the wonderful HVAC-calc software and I chose "average" as infiltration level. It's a 2-storey house, 16 years old, 2x4 timber frame construction, about 1470sqf usable space (without basement). The design conditions were for Kitchener, Ontario, Canada: outdoor summer temp = 85F, outdoor winter temp = -2F, summer grains of moisture = 98, indoor summer temp = 75F, indoor winter temp = 70F. And the total heat loss resulted as 30,533 BTU, which with a 20% additional safety factor would be 36-37 kBTU/h. The calculations were done considering triple glazed window (using good German uPVC tilt-and-turn profile with Uw = 1.2) and R-48 attic insulation (closed-cell sprayed foam insulation).
I could attach the detailed PDF report, and also the exact BTUs needed per each room, if you wish to see more details.
The old forced air furnace (came from the builder) was sized for 50,000 BTU. Another contractor (when I was still contemplating the idea of going with forced air via a new system using a mod-con furnace like Trane) was doing his own Manual J calculations and said that he would go with a 60,000 forced air furnace.
The main idea is to install about 12 or 13 radiators (3 in basement, 5 main floor and 4 or 5 upstairs), route them using a combination of manifold and reverse supply-return connection, via either copper or pex-al-pex (this has yet to be decided) and use either only one zone for everything, or design 3 zones (one per each floor) and have thermostats (Vitotronic remote 200 ? - which is a bit expensive) on each floor.
We aim for a low system design temperature - 130F supply and 110F return, to increase the overall fficiency of the system. But somehow at the expense of larger rads. We would have only one primary heating circuit. There is no need for any secondary like DHW because I have already a separate Rinnai RC98i tankless water heater for that.
I'd like to ask you a few questions, maybe you can help:
1. Which Viessmann boiler is more appropriate for that heat load (to avoid short-cycling): WB1B-26 or WB2B-19 ? I also understand that the WB2B comes with that outdoor reset sensor and the Vitotronic 200 can offer better temp control overall. The only drawback that I see with WB2B is a higher cost plus the lack of an integrated recirc pump.
2. If we were to go with WB1B-26, would that internal recirc pump be enough for the whole system (acting as a boiler + system pump) or in fact you have to use an external one? If we go with WB2B-19, we would have to use an external pump anyway - Viessmann product docs recommend Grundfos UPS15-58F, Taco 00R or
Wilo Star S-21FX - either of them priced at around $100 at ecomfort.com.
3. Is a primary-secondary hydraulic separation really needed? Things like low loss header or closely spaced tees? As I said, there will be only one circuit - we wish only to heat the house via those 12-13 panel rads. When I look at some installation examples via youtube or via heatinghelp, I must admit that I get scared a bit of the complexity (mixing valves, differential pressure valves, 3 or 4-ways diverting valves, low loss headers, zone pumps and many valves on and on). Should it be really that complicated - considering our needs ? :-)
4. Is there any special sizing formula for choosing a pressure tank? Can I chose whatever is at eComfort.com?
5. Is a multi-zone system really necessary (motorized valves and controller)? I'm afraid a bit of this topic because by father has never used them so far. What I basically wish to have is this: in the basement turn the heat completely off, or very low (since we don't visit it too much for the moment), in order to "route" more heat to main and upstais floor. Many people were telling us that the zones will create more flexibility and comfort and you can still use only one recirc pump. My father says that we could simply turn the heat off by adjusting some valve at the manifold in the mechanical room in the basement :-). Could you recommend some good zone valves and their controllers?
6. Would you be able to recommend what other things would be needed, at a minimum: besides one recirc pump and one pressure tank, what other valves and sub-systems would you recommend? Is a mixing valve or differential pressure stuff needed?
7. Could you recommend better US suppliers, eventually available online (I don't drive for the moment and have no car, shame on me), with better prices?
8. Is ecomfort.com store to be trusted? Has anyone had experience with them? They seem to have good shipping rates to Canada (300-350US via LTL truck) and I could engage a customs broker to clear the stuff at the border.
9. Would you go with copper piping or pex-AL-pex? It's funny that Europe started with pex first and now they use copper everywhere. And in north-America it's exactly the opposite. My father wants copper (me too I like it due to being straight and rigid) but I tried to tell him that 1 meter of hard "L" copper pipe costs about $7.90 CAD for 1/2'' and $14.50 CAD for 3/4''. He said we would need about 10 meters 3/4 and 40 meters 1/2. Is that way too expensive comparing to pex-AL-pex? What I like about pex-AL-pex is that it will survive better in the basement against freeze and also being plastic coated, it will keep the hot water warm and less losses on the circuit until it gets into the rads. On the other hand, pex can't stay perfectly straight (looks uglier below the rads) and the pex fittings cost more.
There would be many other questions, such as if my 130/110F system design temp is a realistic one and if my calculations for the rads are ok (that is, if they cover a worst case scenario). But I'll leave other questions for later because I already wrote a whole story here :-)
Thank you everyone for your time and I appreciate all your insights.
[kindly see the PDF attached]