Tempering tank for hot water system

I've already considered this and the tank does not sit very far away from the floor drain. Thanks, Steve

after being agains this originally i believe its a good idea, my concern would be legionaires disease

Has anyone actualy got legionares from a HW tank. Doesnt it need open air to establish and breed.

yes it was in the sealed and pressurized water system in that hotel. it grows in warm water.

they used repeated pure bleach to kill the bacteria

What hotel, the only hotel I heard of it was in stagnant water from AC chillers or other AC equipment. I can understand non chlorinated, warm pooled water growing anything, but chlorinated, sealed, moving, pressurised systems, no I have not heard that as fact.

the old heater sounds like a ideal growing medium:(

Q. What water conditions are best for growth of the organism?

A. Warm, stagnant water provides ideal conditions for growth. At temperatures between 20=EF=BF=BDC-50=EF=BF=BDC (68=EF=BF=BD-122=EF=BF=BDF) = the organism can multiply. Temperatures of 32=EF=BF=BDC-40=EF=BF=BDC (90=EF=BF=BD-105=EF=BF=BDF) are i= deal for growth. Rust (iron), scale, and the presence of other microorganisms can also promote the growth of LDB.

Look here for updates on recent outbreaks of Legionnaire's Disease, and you'll see several hotels listed:

OK an interesting point it was in the hot and Cold water of a hospital, no hospital will heat under the 120f code, for a hospital code is probably much higher, but explain the cold water contamination and the fact they heat water very hot.

cold water in such a large building may get warm easy, people are immune supressed, hospitals have labrinth of pipes, some water sources may get litte use with long sit times for cold water to get warm

I'm wondering if the key word there might be "stagnant?" I don't know how long water would have to be stagnant for????? Days? A week? A few hours? I would think in a one family house that water would be moving through the hot water system at least daily. Do you think you would get anywhere close to 100% turnover in a hot water tank at least every couple days depending on usage? In my tanks (tempering tank included) the cold water inlet has a pipe extending down into the tank nearly to the bottom so the cold water entering must rise upward to exit the tank in the hot water outlet.

I just finished piping up my tempering tank yesterday evening. I figured it would take at least overnight or longer to see a change as our cold water is probably 50 degrees F and it took 52+ gallons to fill. This morning when running hot water for the clothes washer, the copper pipe with the tempered water going to the new water heater was just cool to the touch (guessing about 80 degrees F water). The pipe with the cold water that was entering the tempering tank felt icy cold. I took a reading on our electrical service meter this morning so I will be checking it for the next week or so.

Steve

I see them listed, but no details for some of them. The original Legionnaires disease was from a Philadelphia hotel and it was the cooling tower that was infected, not the water system.

One case mentioned in your list had it in both hot and cold water so the temperature did not matter in that case. Another was a hot tub. Another was a fountain. Seems to be may potential sources but cooling towers are one of the biggest. From what I've seen, there is no sure way to eliminate it, but much potential to cause spreading.

Another update: Looks like it just might be a winner.... After taking a couple more days of meter readings with normal hot water usage and other electrical usages remaining fairly constant, I figure we are using about 7 - 8 kwhs less per day. Tempered water going to the new water heater is fairly close to 100 degrees F. I think having the tempering tank near the wood stove with a recirc loop actually piped over the wood stove makes the difference. I'm considering one more piping change to the recirc loop which might capture even more heat from the wood stove....

Happy New Year! Steve

I’ve actually seen people use 1/2” flexible tube copper and wrap it around the stove pipe and the hook it up the way you described