Redesigning / Heat & Hot Water Piping

polyj79

Years ago with advice from another person, during a renovation project I moved my boiler to a cheap unused spot in my home, which happens to be down the hall from my bedroom. The existing system is noisy and most of all it short cycles. I now want to pipe it correctly. At the time I piped my Utica DV 100 boiler & Zone One indirect water heater and a 007 through a 1” x 1” x ¾” black pipe manifold. I installed a reducer ¾” x 11/4” for an 11/4” Taco zone valve and back down to ¾” copper back to the indirect. I have three baseboard zones all controlled with a 4-zone controller with priority all with ¾” zones .The longest total loop is about 145 ft. long with about 85 ft. of standard ¾” baseboard. At some time in the future will split that long loop but for now it will have to stay. (I am on a slab and must go under a doorway) the other zone has 20 ft of baseboard and the last zone has 40 ft. of ½” baseboard. I did add a Weil McLain wm-odr outdoor reset control, which helped the short cycling a bit. I am now ready to redesign the system with primary / secondary piping. I picked up the books Pumping Away, Primary Secondary Pumping Made Easy , & Hydronic Radiant Heating , but got lost about 2/3’s the way through the Primary Secondary . I have attached three drawing to this post, one that is of the existing system, one that has the indirect off the primary and one that has the indirect off a secondary. It would be great to have it reviewed by a professional to let me know what is the best way to go under my circumstance, in addition, what changes I need to make. (Missed valves ECT.) I also am wondering what is the best way to control this setup. Please note: My boiler room is on the second floor and very small (8’ x 6’) with a ceiling height sloping 4’ to 7’.

Supply House Rick

I am not a professional.

I just had a Weil McLain Ultra 3 80,000 BTU/hr boiler and one of their indirect hot water heaters installed. Before going that route, I wanted to understand these systems, so I got John Siegenthaler's book to understand them. I found it very good. It explains primary/secondary systems and why you might wish to use them, and gives lots piping diagrams for typical systems.

http://www.hydronicpros.com/publications/index.php?id=24

I also read the >100 page installation manual for the boiler and the I.M. for the indirect water heater as well.

W.M., for their boilers (at least the Ultra ones) insist on using primary/secondary piping for the heating loads, but recommend hooking the indirect hot water heater across the supply and return piping before they get to the closely spaced tees. I.e., like in your drawing http://forums.invision.net/Attachment.cfm?CFApp=2&Attachment_ID=38227 . W.M. have you put the circulator for the water heater in the return from the water heater, but that may be specific to W.M. water heaters; they say the circulator for the water heater should be the same size as the one for the boiler (in order to get sufficient flow through the heat exchanger that only holds about 1/2 gallon of water).

If you have the installation manual for your boiler, they may go into the same detail as W.M. do, and you might find them very helpful.