Thanks for your feedback! It's probably obvious that I'm a homeowner who needs more education. But, trust me, I've lost lots of sleep perusing this website and trying to educate myself on HVAC in general! Initially, we planned to install a fan coil-2 pipe system that would cool & heat the house with tap water. We have family ties to the Alberta company that owns the patent on it. However, they are mostly into commercial and not really into the residential market, so ultimately we changed our focus and unfortunately after the build began. Although we are semi-retired, have land and water and will eventually pass it all to our children, we still are not interested in the installation expense of geothermal. We just desire a comfortable, efficient system. Therefore, radiant heat with either HP or AC with heat strips as back up are final choice. Can you tell me if a Man J is crucial for the hydronic system? I've yet to see one from any HVAC contractor. It was suggested that I do one myself and honestly haven't done it so I guess I can't complain, right? zl, Dan and MSM, thanks so much for sharing your expertise & experience! Surely you must know how much you influence participants on GW; certainly influence my thinking and decisions!

It could be any number of things: sulfates calcium compounds silica compounds iron compounds etc. Frankly, there is more reason to believe it is one of those listed above than to believe it is bacterial in nature. It does not look like a biological problem - if it were it would be more likely to look slimy, snotty, yucky instead of grainy and dry. The only way to know for certain is to have the material tested by a laboratory. First, ask for a few of the city's water quality reports - that will provide a good start. Second, find a local water lab, call the lab and ask them how to properly sample your water for testing and take them a sample for analysis. At a minimum ask for: TDS pH hardness calcium iron manganese sulfates nitrates silicates alkalinity

There are seven classes of plastics used in packaging applications. Type 7 is the catch-all "other" class, and some type 7 plastics, such as polycarbonate (sometimes identified with the letters "PC" near the recycling symbol) and epoxy resins, are made from bisphenol A monomer.[4] When such plastics are exposed to hot liquids, bisphenol A leaches out 55 times faster than it does under normal conditions, at up to 32 ng/hour.[73] Type 3 (PVC) can also contain bisphenol A as antioxidant in plasticizers.[4] Types 1 (PET), 2 (HDPE), 4 (LDPE), 5 (polypropylene), and 6 (polystyrene) do not use bisphenol A during polymerization or package forming,[74] and thus will not leach bisphenol A into food or beverages. Pex does not have BPA PEX (or crosslinked polyethylene) is part of a water supply piping system that has several advantages over metal pipe (copper, iron, lead) or rigid plastic pipe (PVC, CPVC, ABS) systems. It is flexible, resistant to scale and chlorine, doesn't corrode or develop pinholes, is faster to install than metal or rigid plastic, and has fewer connections and fittings Crosslinking is a chemical reaction that occurs between polyethylene polymer chains. Crosslinking causes the HDPE to become stronger and resistant to cold temperature cracking or brittleness on impact while retaining its flexibility. The three methods of crosslinking HDPE are the Engels method (PEX-a), the Silane Method (PEX-b), and the Radiation method (PEX-c). Several industry participants claim that the PEX-a method yield more flexible tubing than the other methods. All three types of PEX tubing meet the ASTM, NSF and CSA standards.

1) PEX is a generic name. PEX stands for cross-linked (X) polyethylene (PE). I don't know of any specific brand that is generally recommended, but it is good to know that there are three main types of PEX: PEX-A, -B, and -C. The ABC designation refers to the method by which the cross-linking is done - not the quality or rating of the tubing. Each cross-linking method produces different characteristics within the tubing. For example, if kinked or crushed, PEX-A has the ability to regain its shape through the application of heat. 2) Yes, there are several different transtions available. One that comes to mind that is readily available in my area is a piece of copper pipe, bent in a 90° sweep, with a PEX nipple on one end. The other end is sealed and can be cut off after drywall is up. You can then install whatever type of stop you want. 3) You can use either method. Any distribution system is acceptable as long as it meets code and supplies water to all your fixtures with sufficient volume and pressure. Other factors worth considering are the costs and benefits of a trunk and branch system vs. a manifold system vs. some combination of the two. There are many other threads on this forum that cover that discussion. 4) Yes, the PEX should be supported in accordance with your local codes. It's quite tough, and would be fine in most situations just flopping behind the wall, but it's cheap, quick, and just good practice to support the pipe in the wall.