In fairness to all, we don't discuss pricing on the Wall. Thanks for your cooperation.
Help designing constant circulation with CI radiatiors and low mass boiler
I'm in the trades and have a "reasonable" knowledge of heating systems, but need some help with specifics for a house I'm remodeling. The local heating contractors do not have much experience with the type of system I'm interested in, such as has been discussed on this site.
Home is 1920's two-story in Central Maine. Total heat-loss is around 62k btu, the largest space being kitchen/family room at 16.6k loss. Emitters are all original CI radiators, mostly 2x over-sized (i.e. bedrooms have 4.5k btu loss with over 8k in emitter capability).
I'm planning to home-run with 1/2 pex to a radiant style manifold. Boiler is Purepro Trio low-mass oil fired at 79k net IBR (smallest model). I have a hydrostat with outdoor reset capability. My intent is to have a single variable speed circulator and TRVs.
So... which circulator, which TRVs, and what else is necessary? My calculations say 145F water and perhaps only 1gpm, which seems really low. Do I need to worry about protecting the boiler from condensing, and if so, through what method.
DHW is planned to be on a separate system, but if it would be better to do a indirect to keep the mass up, I'll consider it. Do I need a pressure bypass in the system? Should it be primary-secondary? Hydronic separator?
I've read so many threads on here about various systems, and I understand most of it, but some specific layout/equipment info is still needed. My heating contractor is comfortable building whatever I want, but as noted, doesn't have familiarity with this type of system (constant circ, TRVs).
Thanks for any guidance.