OT: Separate hot and cold valves on kitchen taps save energy.

[OFWW]

This is what has been used for decades before the "nipple"

[Spalted Walt]

Hence the the invention of the dielectric nipple:

[krw]

It is. Huh? It's easily treated. Turn up the damned temperature! ;-) It won't survive above 133F, IIRC.

Dishwashers have heaters. It's usually cheaper to let it boost the temperature.

You can mix before the hot faucet.

Our first house (banns second, for that matter) had a domestic water coil in the furnace ("boiler" that doesn't). Of course the furnace was set at 180F(+) and it backed right up to the kitchen and the bathrooms. No mixing valves. The water was *hot*.

[OFWW]

The link above is designed to sell ACME Mixing valves, in order for those to do their job properly all the HWS and HWR lines must be insulated along with that you need a recirc pump or you are just wasting money on the mixing valve.

You should also not that the disease was contracted via your lungs, not your stomach.

In many years of experience in the HVAC commercial and industrial industry I have yet to see any evidence of bacteria in a closed loop system, I have pulled down boilers, HW boosters, heat exchangers of all types and never was their any sign of any growth. Now, that said, once it hits the air and lingers all bets are off. I have seen growth in Hot tubs for general use in Hotels and Motels, Swimming pools, cooling towers of all types. Chlorine is often used to kill it, but especially in cooling towers there are spots where the water pools and flows very little. We also used algaecides or other types, plus they all require constant maintenance, tear down, clean up and repairs if necessary. This is done for a variety of reason, the least of which is any disease.

Think about it. Air? Where in your HW tanks is any air? Air stops water flow or lowers the flow depending on where the air is trapped and we used air bleed on lines to eliminate that.

Really? They are designed for say a 40 degree rise. While the thermostat could be set for 180 deg F and the High limit at 200 deg G, if the incoming water is only 120 deg F add 40 deg F and the best you will see is 160 and that is not enough to sterilize the dishes and pans. Most domestic dishwashers do not publish the deg rise, but the info is out there. Until people make a fuss it'll never be a big deal.

And it should be.

I'd bet. There's a lot of missing info about that system, was it for HW heating, forced air? A recirc pump between the coil and a storage tank, and so on. Whatever, I'd bet that it was an old house and done properly.

[OFWW]

Looks to me like the dielectric coupling was doing its job just fine. No signs of leaks and the galv piping was getting messed up like it normally does.

You can see the flow restriction inherent in the design of the dielectric nipple, and it is considerable.

If I were to install one I would up it in size to the next largest diameter and use bell reducers on both ends to eliminate any problems. Side effect would be an increase of electrical resistance, a bonus.

[Ed Pawlowski]

Then sanitize, not sterilize. The temperature, coupled with the caustic detergents do a good job. My KitchenAid goes to 155 degrees.

A dishwasher that has a sanitizing feature uses an extended hot-water rinse to kill germs. The National Sanitation Foundation has set a standard named NSF/ANSI Standard 184, which means that dishwashers bearing this certification kill 99.99 percent of bacteria when operated on the "sanitize" setting. In order to be certified, they also must reach 150 degrees Fahrenheit during final rinse. Dishwashers that don't have this certification most likely don't reach temperatures high enough to sterilize items.

[krw]

HW heating. The "domestic coil" is a loop inside the boiler used take off hot water from the boiler. When the boiler isn't in use, the water first coming out of the coil is at the boiler temperature, with is 180F +/-19F, IIRC. That house was built in '72, IIRC. Our second (same issue but the boiler further from the points of use) was built in '86.

[krw]

They may be "designed" for a 40F rise but they will raise the temperature to whatever they're "designed" for. They are thermostatically controlled.

>

[Spalted Walt]

Judging by the cluelessness of your last statement, I'm sure I've seen your handiwork before. ;)

[Ed Pawlowski]

Had the same system in my house. Terribly inefficient. On a hot August night you'd hear the burner fire up to keep that poorly insulated coil hot. Replaced the boiler with a more efficient system with an insulated tank indirect heated and got a 40% decrease in oil use.

[krw]

The advantage is that it keeps the boiler operating in the summer so it doesn't rust. When oil was cheap, it was cheap insurance. Of course I wouldn't have oil heat these days.

[Ed Pawlowski]

That cheap insurance would have cost me over $1000 at last years prices. New boiler saves me about 350 gallons a year. I put in an Energy Kinetics System 2000.

I'd switch from oil if I had a good alternative. Gas is too far away, propane is no better.

[OFWW]

Commercial Dishwashers (NSF/ANSI 3)

? Must achieve a minimum 99.999 percent or 5-log reduction of bacteria ? Must reach a final rinse temperature of 165°F for stationary rack dishwashers and180º F for all other commercial style dishwashers

You might have noticed that for domestic dishwashers I did not set a min temp setting, ("say")

However, they did not speak to a specified temp rise on the HT booster temp, which I imagine is that electric coil in the bottom pan.

[OFWW]

When I read that I see boilers that are quite a bit larger than a domestic types, but they are high maintenance unless you had a good water softener or naturally soft water, due to calcium build up in the coils.

I would have set the set point @ 140 during the summer season to save a lot on fuel, unless you live in a cold area of the country.

Due to efficiency requirements in Calif, there has been a lot of changes in all types of heating systems.

[OFWW]

On Mon, 01 Feb 2016 20:42:09 -0500, krw wrote: snip

You might want to check on that, if they are rated for a 40 or whatever degree rise then that is all that they can do.

[OFWW]

ROTFLOL, Sorry Walt, but you are as wrong as wrong can be. Think about it, anytime you put in a fitting with a diameter less than the piping around it, you have created a restriction. If you cannot understand that, well..........

[krw]

Understood. When I owned the house, oil was less than $1/gal. The "insurance" was something like $50/yr.

Our second house (in Vermont), we had switched from oil to natural gas, not because of cost. Our houses since have been electric/heat pump. Our current system will probably have to be replaced in the next few years. :-(

[krw]

Thermostats don't measure temperature rise.

[Spalted Walt]

3/4" Camco dielectric nipple I.D. 0.75 in 3/4" type M copper pipe I.D. 0.811 in Difference .061 or ~3/50 in

So by all means, you go ahead and "use bell reducers on both ends to eliminate any problems".

BTW, nice sink!

[krw]

NO, they're used for even small homes, too (~100KBTU). Yes. You bet!

That's the usual recommendation. I can't remember why we didn't do it. There was something screwy with the temperature controls on the thing but I don't remember the details.

Retroactive? Yeah there is a lot of difference between $.79 oil and $4.50 oil, too. Of course the price is down, now, but it's still worth some work to save.