No problems with odor here. Seaward had informed me that there was not a problem with running antifreeze through the unit, and didn't mention anything about odor or anodic degradation. That said, with all the commentary about odor, I was prepared to have that to contend with, but again, no odor.
Anyhow, an excerpt from a thread I read elsewhere follows. I cannot take credit for it, and can't remember it's origin, although I believe it is useful information. Regardless, I had no odor issues, and did not have to go through this process. Here's the information for anyone who is interested.......
Water Tank Re-commissioning
Fresh water system problems--foul odor or taste--are typically caused by allowing water to stagnate in the system. Although most people think only in terms of the tank, the plumbing is actually the source of most foul water, because the molds, mildew, fungi and bacteria, which cause these problems, thrive in damp dark places rather than under water. Many people—and even some boat manufacturers—believe that keeping the tanks empty reduce the problem, but an empty water tank only provides another damp dark home for those “critters.”
There are all kinds of products sold that claim to keep onboard water fresh, but all that’s really necessary is an annual or in especially warm climates, semi-annual re-commissioning of the entire system—tank and plumbing. The following recommendations conform to section 10.8 in the A-1 192 code covering electrical, plumbing, and heating of recreational vehicles. The solution is approved and recommended by competent health officials. It may be used in a new system a used one that has not been used for a period of time, or one that may have been contaminated.
Before beginning, turn off electric power to your water heater at the breaker; do not turn it on again until the entire re-commissioning is complete.
Icemakers should be left running to allow cleaning out of the water feed line; however the first two buckets of ice—the bucket generated during re-commissioning and the first bucketful afterward--should be discarded.
1. Use a solution of 1 pint Purex or Clorox bleach to 25 gallons of water). With tank empty, pour chlorine solution into tank.
2. Complete filling of tank with fresh water. Open each faucet and drain cock until air has been released and the entire system is filled. Do not turn off the pump; it must remain on to keep the system pressurized and the solution in the lines
3. Allow to stand for at least three hours, but no longer than 24 hours.
4. Drain through every faucet on the boat (and if you haven't done this in a while, it's a good idea to remove any diffusion screens from the faucets, because what's likely to come out will clog them). Fill the tank again with fresh water only, drain again through every faucet on the boat.
5. To remove excess chlorine taste or odor which might remain, prepare a solution of one quart white vinegar to five gallons water and allow this solution to agitate in tank for several days.
