BIPVguy,
A great design guide is the publication "Planning and Installing Solar Thermal Systems" by the German Solar Energy Society.
The Viessman software is available for purchase (about $100 Cdn) and has some customized systems based on their controller schemes. Whichever supplier you end...
Maximum spacing between the tees should be less than 4x the pipe diameter of the primary pipe in order to minimize the pressure drop between the supply and return tees. You want to minimize the pressure drop to hydraulically separate the injection pump system from the primary system.
John...
Have to agree with DRweig regarding the ventilation strategy. Decoupling of the ventilation and H&C systems simplifies controls and can increase overall energy efficiency as you don't have to supply excess fresh air to the other zones to meet the O/A requirements of the critical zone.
I...
This may be a good question for a CIR (credit interpretation request) for the USGBC to response too. You may want to check through the existing CIRs on the LEED website to see if this has been addressed in a previous LEED project.
I disagree dvd. The concept of exergy can be very helpful as it is an indicator of the quality of energy source or flow; something not accounted for in a 1st law analysis.
Chris,
we've been dealing with the same issues up here (in Canada). We've been running the hot water recirc line (or heat trace) down in the wall to the fixture.
There are a couple of other options:
1. use an instantaneous water heater mounted near the bank of Lav's. Personally I don't like...
You need to determine the ventilation load in order to determine Q. Then you can determine the s/a temperature.
1. Q = 10,000 btuh (skin losses) + Qvent (TBD)
2. determine mixed air temperature. Say the outside winter design is 16 deg F (Vancouver, BC design). Then the mixed air temp would be...
Assuming we are dealing with a sealed buffer tank, completely filled with fluid, the pressure drop across the tank would be negligible due the very low fluid velocity in the tank. Hydraulically, the tank is acting like a low loss header or hydraulic separation.
That being said, there will be...