ISERIES MIXING VAVLE VS. BUMBLEBEE CIRC

pipeking

   like everyone i want to save on my fuel bill (oil). i have a ranch with 2 zones, i've done a heat loss by room and each room is over radiaded by 500-1500 pending on the room. my boiler is sized right but is very generic, tanklesscoil,taco heat head zone valves, honeywell 8124 aquastat,and 1 pump. since i cant lower the temp in the boiler cuz of the tankless, howabout a taco iseries mixing valve 4way w/odr. would this make my boiler short cycle. can i have my burner fire off hi/lo aquastats and not fire on call?

  or what about a delta/t circ like the bumblbee. i never used a delta/t circ before, ive used the alpha, but thats delta/p.   i am willing to change anything but my boiler,radiators,and adding a inderect cuz thats all out of my price range.  what kind of controls and or nearboiler piping will be the absolute most fuel efficent setup,

icesailor

Easy (cheap) way out:

Install a third world Indirect. An "I" Series mixer will cost you close to an electric water heater and you will still need to keep the boiler hot for the tankless.

I install a 40 or 50 gallon electric water heater WITHOUT CONNECTING THE 240 VOLTS!!!!

Pipe the water heater like it is the only source of hot water (it is) and install a Taco 006 BT 3/4" IPS bronze circulator on the bottom of the tank. Pipe the outlet into the cold water inlet and the hot outlet to the cold water inlet of the water heater. Connect the bottom thermostat of the water heater as a switch to turn the pump on and off. Connect it to a plug. You do NOT need to wire into any boiler controls. Turn the  high limit of the 8124 to 160 or 170 degrees. Set the "lo" to in the 8124 to 140 degrees. The boiler will maintain 140 degrees that will protect against condensation. If a thermostat calls, the 8124 will flip up to high limit and whatever you set it for will be your system temperature.

There is no more effective way to make hot water and cut back on your system temperature than that.

If you are used to the quick recovery of what you have, you could be unhappy with the modulating ODR of an "I" Series valve. It all depends on what you are willing to spend.

I have the same system as you with a storage tank. I came back from Florida after New Years and my heat had gone out. The house was 36 degrees. I run the system at 160 degrees until it gets really cold, then I raise it to 170 degrees. It was so slow in recovering that I turned the high limit to 190 so it could catch up and warm the house.

It works for me.

I have a Wilo ECM circulator with my 5 Taco 572 zone valves. The Wilo may speed up and down, but I don't see any savings or imprrovements. At least not like I would if I had what you have and did what I have.

pipeking

YUP!

I'VE DONE THIS IN ALL DIFFERANT CONFIGURATIONS, NOT BY CHOICE, JUST WHAT EVER THE CUSTOMER WANTED. MY FAVORITE WAY IS JUST LIKE U DO IT, BUT SOMETIMES I CAN'T CHANGE THERE MIND. I ALWAYS WANTED TO TRY IT SETUP JUST LIKE A INDERECT AND MAKE IT A COLD START BOILER. HAVE U TRIED THAT OR HEARD OF THAT? WHAT WHERE THE RESULTS.

  ALSO I LIKE THE IDEA OF CONSTENT CIRC. WITH A MIXING VALVE AND ONLY HAVING THE BOILER FIRE WHEN IT NEEDS A BOOST. ONE THING I'VE BEEN THINKING ABOUT FOR A LONG TIME WAS BIODEISEL!! THERE IS NO SULFUR IN BIODEISEL SO IF U HAD CONDENSATION IT WOULDN'T MAKE ACID. NOW OF CORSE CONDISATION IS NOT GOOD FOR YOUR FLUE AND BOILER BUT ITS JUST SOMETHING I'VE THOUGHT ABOUT

SWEI

biodiesel

Burns clean and has fantastic lubricity, but there are caveats:



It doesn't like cold (cloud point and cold filter plug point are both possible much of the winter.)



Its solvent action does a number on NBR O-rings and washers.  A fluorpolymer like Viton will work.



The residual methanol attracts water, making it hard to keep dry (several times more water than you get in dino-diesel.)







...and PLEASE DON'T SHOUT when you write.

pipeking

SORRY FOR CAP LOCK

once i notice it was on i didn't want to rewrite the post. and then forgot to say sorry!lol

pipeking

WHAT ABOUT COLD START?

 anybody try coldstart using the tankless for the electric tank inderect?

icesailor

Cold Start:

Run it cold start if you want. Cold start is hell on oil boilers. Running 140 degrees will stop flue gas condensation. That is the temperature maintained by the boiler controls. If you wire it like I suggest, there will never be any hot water because the 8124 controller will always be satisfied. If you try to get hot potable hot water, it may be cold. The only way to get hot water in the tank is if you have a heating call.

Are you thinking that you will connect the electric hot water tank to 240 volts, and a 20 amp electrical draw? You don't. There is no wiring to the elements in the electric water heater. The only electrical connection is to the bronze circulator with a trip through the lower water heater thermostat to act as a switch. When the bottom of the tank gets cold, the pump starts. When the bottom of the tank is hot, the pump stops.  The boiler control (8124) has no idea what is going on unless told so by a heating  zone thermostat. The boiler operating control (Low Limit) maintains 140 degrees. The DHW comes from that. When the water around the coil gets cool, the burner starts. When it gets hot, the burner stops, The zone heating circulator never starts.

Its so simple that it is stupid.

Paul48

re:Cold Start

I think you'd be disappointed in the available hot water. There would be a considerable "cold sandwich" in there. I also dont like cold start boilers. I believe they have a shorter life-span. Run the low limit at 150 tops.Ooops.......a really cold sandwich.....It won't work at all using ice's method. I forgot he was just using the boilers ability to maintain.

pipeking

lack of info...

  i should have told the hole story. i would wire just like a inderect,  and make it its own zone. either use a hi limit aquastat or cut the leads on the 8124 lo-limit,whatever. so basiclly what im asking is do u think having 3 zones w/1 of them being the elct tank w/the tankless inderect on a cold start be more fuel effiecient.

icesailor

Once again:

Once again.

A oil boiler with a tankless only will make all the hot water you want. The bigger the input of the boiler, the more hot water you get. You have the operating temperature, that must be enough to give you hot water performance, and the High Limit, that gives you the water temperature that heats the building. You need a tempering valve on the DHW/tankless to even out the flow.  If you have a great big humongous boiler, and a not very big draw, you don't need the boiler water to be very hot. If you have a little bitty P Pot boiler with not a lot of nuts, you need to run the boiler very hot to get DHW performance.

If you have a small boiler with a small draw, you can make a lot of hot water in a long period of time by storing it. If it is a point of use tankless coil, you will run out quickly.

We don't discuss pricing here. In the abstract, how long would it take you to connect an indirect through the boiler piping with a dedicated circulation pump plus wiring and controls, connected to the potable water system?

How long will it take you to connect an electric water heater to the potable water system, and then connect the tankless coil to the water heater? You only need a cord whip and an extension cord to connect to the closest outlet until the electrician comes by and can't understand it.

No new boiler piping. No new boiler wiring. True plug and play.

Its an indirect with the coil in the boiler, not in the tank. You pipe the coil to the tank. not the boiler to the tank or coil.

Comprende'?

icesailor

I don't understand?

I don't understand?

"It won't work at all using ice's method. I forgot he was just using the boilers ability to maintain."

It won't work?

pipeking

then what???

  i don't like cold start either it distroys boiler's. but when u don't have a tankless coil what do u do?

Paul48

ice

if he was to make it a cold start boiler, your indirect wouldn't work.

pipeking

no huh...

 it wouldn't work cuz the coil is to small?

Paul48

LOL

This is like a Russian, a Frenchman and a Swede trying to have a conversation.

icesailor

Cold Start:

Absolutely. It wouldn't work.

How would you make hot water with a cold boiler?

I keep having to remember what my good friend Max the electrician says.

"They're smart, we're (I'm) not".

If you want cheap hot water with what you have. do what I do. If you want expensive hot water another way, do it that way.

Me?

This morning at 400 AM, I got in the shower and had a really nice hot one. Then, I brought my stuff down and put it in the washer and ran the load. Before I left at 5: 30 AM, I ran the dishwasher. I had hot water for all of it. Mine works. Well.

icesailor

Tankless:

This started because you said you had a tankless coil in the boiler. If you don't have a tankless coil in the boiler, then buy an indirect with a coil.

My discussion only applies to oil boilers with tankless coils. Some want to install an indirect on a boiler with poor tankless performance. I say, use the coil, add a water heater as a storage tank.

And that's all folks.



Like this:

icesailor

Coil size:

The coil size is never too small.

I give up. You're smart, I'm not.