Hello all,

2 Questions: 1.) Best practices for modeing domestic hot water in Trace. 2.) How to incorporate solar thermal hot water into a Trace model.

Q1. Typically, I set up a base utility with the full load hot water heater demand (say 10KW or 40MBH) and then use a schedule. I see that you can call out units of gpm and also call out entering and leaving temperatures in the library...is this a better way? I might think so because typically on a WSHP system I might put a HX in the source water piping so when source water is a higher temp than entering domestic water, I can capture some preheat.

Another item I find difficult is assiging heat from a heat recovery chiller to domestic water heating or using a water to water heat pump, so some ideas here too might be nice, if you have any...

Q2. I've seen the video on "modeling" solar PV and was wondering if folks are using this method to model solar hot water too. Typically what I do now is assume, calculate (with RetScreen or T*Sol), or estimate the solar fraction, and then just reduce my proposed buildings water heater size accordingly. For example, for a 10KW baseline hot water system and a 30% solar fraction, the proposed building would use a 7KW heater modeled like above.

Thanks for your ideas!!