I don't use CSST on equipment which may be moved often. It is used to make odd bends and curves around objects, but once installed, it should stay in place. For equipment that moves, I specify a Mason CSAWN which is CSC International certified for use with natural gas.
I am thinking the valve prohibition has to do with the atmospheric type of vacuum breaker as a downstream valve "could" cause an occurrence of constant pressure and would not allow for the vacuum breaker to function properly. The prohibition would not apply to a pressure vacuum breaker or the RPZ.
I would assume there would be more than floor drains in the building. Since there will be grease laden waste, it is likely there could be a dishwasher and/or three bowl sink to wash/sanitize pots/pans/baking containers. These could flow a lot. The ME needs to give you information on that...
I have found the pay is sometimes less in making the switch in that construction personnel get paid overtime and they may not get paid that on the design side. Some that I have known have taken fairly significant pay drops making the switch. Of course, you don't have to freeze your ### off or...
Plumbing Codes typically do not allow push type joints in a building.
They also typically require some type of lateral support at changes in direction when the pipe is in the size range being discussed. Typically would use something like...
LI
Yeah, nobody complains about having too much hot water.
But, when the conservative guidance can be 2-3 x what is actually needed, it is not in the owner's best interests.
One of the ASHRAE handbooks (cannot remember which) shows the modified Hunter's curves for hot water. The charts are useful for showing the interplay between generation (KW of the heater) and storage (gallons). One caveat is Hunter's is very conservative so you need to consider that.
100K for only 7 years experience in HVAC, even with a PE - you must be in a fairly high cost of living area. That being said, you are not likely to get much more blood out of that turnip except for annual raises which can change based on economy. Also, I would not depend on bonuses for...
Back to the plumbing side. As long as there is a backflow preventor installed on the make up water connection from the DCW and the heat transfer of the two systems are separate - there is no code issue. Double wall heat exchanger is not required as the heat transfer is from gas combustion and...
If you want, just put two Navien heaters and a RPZ backflow upstream of the space heating unit to make that water non potable. Since it will be based on flow rate, it will be accurately sized and when the space heating is not used, the water heater will not be operating. Since it will be non...
Not only do you have to maintain the potability of the water (during summer months when there is very little if any heating hot water demand), you may also have to comply with Lead Free requirements of all pipe/fittings/valves/equipment in contact with the water.
I agree tables can be a quick check on things and I use them as such.
Your table seems to be a bit more conservative than the code tables, which is not bad. The reason I don't like the tables in the IFGC is the more recent versions got rid of the first table from 2003. The table from 2006...
Seems it didn't load the 2003 version.https://files.engineering.com/getfile.aspx?folder=c1b61aae-a700-4456-896b-32a172815e46&file=Screenshot_2003_IFGC.png
I have never liked the use of tables for sizing natural gas piping.
The 2003 and 2006 IFGC give differing guidance which differs from your table and leads to confusion.
https://files.engineering.com/getfile.aspx?folder=e9607083-d6a8-4dff-99cf-843f302f24c8&file=Screenshot_2006_IFGC.png
