4 way mixer or...

Tony_8

looking at a project tomorrow using a solid fuel boiler for radiant. Boiler must, and will, run too hot for direct circulation. I like the 4 way concept because it seems simpler and less expensive to install. But is it ?

The tubing's in the floor already and sounds like it was done properly, 6-200ft loops of 1/2", 2" blueboard under whole slab, etc. Only thing I will find out on-site is type of tubing. If it's non-barrier the question is moot, I'll use a plate HX.

Thanks for your input,

Tony

Mark Hunt

Nothing wrong


with a good 4-way.

Mark H

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Contractor"

Tony_8

hey Mark !

Thanks, that's my inclination.

Customer says this is what he wants for Christmas, to have his floor warm. I told him Santa takes cash or checks

BTW, got that "smokepole" ready ? I NEED the extra week to get enough deer hunting in. Only about 20 hrs so far

Mark Hunt

Smokepole!


Got out this afternoon. Watched about 20 turkeys fly up to roost.

On the house we are currently doing, we will be using Viessmann motorized 3-way valves for water temp control. No need for 4-ways as the Vitodens doesn't care about low return temps.

I'll be back out Saturday with the smokepole. I hung two during the regular season, I have two more tags to fill.

Best wishes!

Mark H

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Contractor"

Radiant Wizard

3-Way

I have been using them for years and it's the only way I control all my radiant. I think injection is a product of good marketing while the Europeans have been using 3 and 4-way's for years. Never had a problem.

Mark Wolff

Variable Speed

All my infloor systems (over 10 this summer) are by variable speed injection pump. I saw a study, I'll look for a copy to post, that weighed the benefits of both. The floating action 4 way valve is initially about 5% cheaper for you to install, but in the long run costs about 15% more in electricity to run than if it had been by variable speed injection.

I personally like the variable speed injection system better, it looks nicer, is easier to troubleshoot in my opinion, and offers more flexibility for multiple manifold setup (seperate staple-up and slab). I guess its six of one, half dozen of the other, but don't count injection out, its a really good idea.

Unknown

Why?

I'm still trying to understand why one is better than the other. Is it just opinion? Is there a reason?

Noel

Steve Eayrs

We use almost all injection pump, w/ some 3-way for small systems.
I have not found them to cost more than a good 4-way, if you compare with a motorized 4-way. In fact I find it easier to pipe a injection and cheaper if you use a basic injection control. Any of the Tekmar injection controls are also going to give you I/O control.
The 4-way is only cheaper if you are not concerned about I/O control, which I am. Makes a big difference on comfort.

Steve

Radiant Wizard

Noel

There is no SYSTEM advantage of one over the other in my opinion. It's a matter of preference.

Injection was born in the late 70's in Northwest Canada and the US where radiant system were being installed without O2 barrier tubing. They were finding that mixing valves were failing due to O2 diffusion so they had to come up with a way to mix. The birth of Tekmar.

I feel they just have done a good damn job of marketing over the past 5 years and if somone out there can show me that injection is better I'd like to see it. There must be a reason why the Buderus' and Viessmanns out there promote 3 & 4 way mixing.

Unknown

There must be, you're right!

What is it, I wonder....

I've used both methods, but on cast iron radiator systems that someone put baseboard zones onto.

I simply don't see the huge advantage of the "old fashioned 50's technology" (to quote your words) mixing valves over injection mixing.

Or vice versa.

I'll keep searching, but I think both have there places, relative to cost, system size, and maintenance.

Parts, when suppliers are closed, are easier to find for injection systems.

Both can be run manually if they fail at the control.

It's a toss-up, to me. Your reasoning amounts to adamant preference, as I see it.

Noel

Einsiedler

cost (4W vs INJ)

I have priced many both ways and found that Injection wins. (price wise).

Injection= Inj_pump + controller + maybe a relay for secondary pump.

4Way = mix valve + motor + controller

I can supply a T#356+ up15-42f for a lot less than the 4-way motor alone (T#011)

either way works fine. 4-way is nice that you control return temps to boiler better, but don;t think this is an issue on this one.

good luck..
EIN

Einsiedler

cost (4W vs INJ)

I have priced many both ways and found that Injection wins. (price wise).

Injection= Inj_pump + controller + maybe a relay for secondary pump.

4Way = mix valve + motor + controller

I can supply a T#356+ up15-42f for a lot less than the 4-way motor alone (T#011)

either way works fine. 4-way is nice that you control return temps to boiler better, but don;t think this is an issue on this one.

good luck..
EIN

hydronicsmike

My opinion

Wizard -> If Variable Speed Injection can give birth to something like tekmar, then how could it be bad? I gotta have one of those in my Basement too (already have three). -;)
If I was told the right story, then it would have been tekmar who gave birth to Variable Speed Injection.
Keep in mind, tekmar always has and still does sell Mixing Valves.

Would you say that tekmar has only come up with Variable Speed Injection Mixing Systems to prove that strong Marketing can generate enough sales to post steady growth in over 30 years to become a key player in the North American Market place, OR, to address todays Applications and come up with alternative solutions to allow for more flexibility?

Tekmar, Viessmann and Buderus are all companies from the old Fatherland. Being a German myself, I know that all that is really worth anything in this world and actually works, comes from there too! If it aint European, it aint good. At least I thought so, because this is what stubborn Europeans do!

Today, I have learned that this is not necessarily always true. Although I don’t want to take anything away from any European Product and its extremely high quality, I can see a lot of high end products on the market that are not from there. In fact they come straight from HOME, North America.
Where did this silly talk come from, where we must praise all that comes from Europe and all that’s done and developed here is worth less?

This topic has been discussed over and over again. Some say its preference, others have their own views of why Variable Speed Injection is better. Others lean towards the good ol’ valves.

Where I came from, Variable Speed Injection does not exist. Its all done with Valves. It has been for years and years. Once you have done something for years and years, its hard to change all of the sudden. Especially, if it worked for you until then. Can’t blame anybody either for that.

Today, I favor Variable Speed Injection over Mixing Valves, because I find that

- a complete Mixing Valve System with Actuating Motor costs more than a Pump that I can vary the speed of (keep in mind that I sell Valves and not Pumps)

- an Actuating Motor reacts much slower to temperature swings for Setpoint operation or Boiler Protection than an Injection Pump can because of its physical Motor Speed limitation (ranging between 60 and 250 seconds from fully closed to open)

- Mixing Valves can fail or get stuck because of corrosion inside, if not exercised properly every so many days, where Pumps tend to have less issues with that.

- Mixing Valve Repair Parts are more expensive and not as easily accessible. Who’s got a 3” Repair Kit on the shelf? How many Distributors have another pump on the shelf?

- It’s NOT easier to replace or repair a Mixing Valve over an Injection Pump. I wish I had true numbers to back this up too, but if I believe most of what my customers are telling me, I hear a lot more about Mixing Valves being replaced or repaired than Injection Pumps per %-installed

- Mixing Valves have to be sized to accommodate the full system flow, where Injection Pumps only have to be sized to handle enough flow to compensate for the deltaT across a system loop, which causes an Injection Mixing System to be generally much smaller than a Mixing Valve System

- Siggy’s Minitube Injection System doesn’t work with Mixing Valves. Siggy’s one of the best and brightest men (If not THE) in the industry and what he says counts!

I could still go on, but that’s enough for my feedback. Valves or Injection Pumps? Who cares, as long as the customer gets the most comfortable and most efficient Hydronic Heating System possible in the End.

Variable Speed Injection Mixing is growing in Europe as well. Wait!!

AND, before I forget, Variable Speed Injection Mixing DOES WORK on Condensing Boilers! Who came up with the nonsense that only 3-Way Valves work? It may not be as easy and convenient to pipe, but.......KISS.

Allied

Injection Mixing 1968

Siggy traces Injection Mixing back to 1968. Also discusses on/off injection mixing vs. variable speed injection mixing.

Siegenthaler on Inspirations from the Past (5/01)

Also you might enjoy his article on a system that uses both variable speed injection and manual 3-ways.

Siegenthaler on A Signature System (6/02)

The new edition of his book supposedly covers it in greater detail. Just as soon as I can afford it.
hydronicpros.com

hr

I favor VS injection also

nice to be able to transport 300,000 BTU a couple hundred feet across a shop with 3/4 or 1" pipe size. (mini tube injection)
Price a 4 way, operator, piping, and labor to do that with a 4 way


hot rod

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Contractor"

Tony_8

went with...

Tekmar VSIP. MUCH less expensive to purchase, and looks like it'll be easier and less costly to maintain. Compared it to Tekmar 4-way (motorized) and costs about 1/2 !