Very nice looking job indeed. I would like to learn something from it,
so here are my questions.
Is this residential application?
There is a group of valves to the left of Tekmar controller.
Two gate or stop valves with green handles and ball valve between them. Why three valves in a row?
What is the brass part above these valves?
Yes this is for a residential application. The valves to the left of the Tekmar 363 are a ball valve with boiler drains on each side for filling. The brass part above the valves is the automatic air vent, a Honeywell Sparco Powervent. Those Powervents work very well.
is this a low temp application?
how are you heating the house? air handler/baseboard/cast radiators?
there is a lot of water movement if all zones are calling?
is a 1" feed to supply adequate??
just some thoughts
Yes this is for a low temp application. The upper pump feeds a floor with above-floor heat transfer plates. The next one down feeds a manifold for the lower level slab. The house is around 2000 sqft so 1" feeds are more than adequate.
As for the blower motor, you could mount one behind the whole thing and heat the mechanical room ;-)