Taco I Series Mixing Valve not working?

Drewgrizz

I have finally got my boiler setup installed and working and it works great, but the Taco I series 4 way mix valve is not working correctly and I want opinions on what to do. I built the secondary piping just like they show on the diagram and wired the 4 way to the input/output/odr sensors, but when I plug it in it makes the typical racket and the green lights blink, but no hot water is sent out to the manifold. Actually the water in the return leg is warm, but cold on the output. I have tried adjusting all the dip switches but nothing changes. Do you guys think its a faulty mix valve, should I call Taco? I unplugged the thing and used the manual dial to create flow out to the manifold and the setup works like a charm, but I would like the outdoor reset function even thought the bumblee's set on Delta seem to keep up. Every once in a while the house gets alittle hot, but its usually when it warms up outside real fast.(ODR would be nice) System is a 90k boiler setup primary/secondary with bumblee's on both sides(primary is set on constant1, secondary is set delta t20*) Taco I series 4way and manifolds out to Myson rads with trv's. I must say the system is awesome if I turn the trv's all the way up it will run you out the house and thats with 160* supply temps. I have around 44k btu's worth of rads in a 1200sqft 100yr old home.

Snowmelt

Call

Call Taco I am sure they will help it's mostly something silly.

icesailor

Not working:

Everything is in the head.

I can't imagine how you have wired it. It sounds like you have made it incredibly complicated. I don't understand why you used a Bumblebee on the supply side of the 4-way. The valve modulates the water. You have two competing devices trying to operate the valve.

Whatever you have done as far as wiring, disconnect all of whatever you have done and just wire it as basically as you can make it. The circulator for the boiler side and the system side must come on together. Make it run that way.

Are you sure that it is piped it correctly? I find the valve extremely easy to connect it backwards. Especially if the boiler is to the left and the valve flow imposing is away from you. Even if you mark the flows and inlet and outlet, it is still easy to reverse it. If you have a problem unplugging a tool cord from an extension cord, and throwing down the extension cord so you can plug the new tool into the old tool, and not the extension cord that is now on the floor, I'd double check the piping. Without power, the valve powers cold. If it is backwards, when it should get hot, it gets cold. You can't change it.

Is the return sensor clamped on the return and well insulated against the pipe?

Bumblebees are going to overly complicate something that is as simple as opening your fly first.



IMO

Drewgrizz

taco

Its not overly complicated I used a bumblebee on the primary side for its high eff motor and the one on the secondary is wired for delta t operation with a supply and return sensor. The boiler is being controlled by its high and low temp internal settings. The 4 way is to control the temp of the water being injected into the system and the TRV's are like thermostats on each radiator. Its actually a very simple system everything is controlled by its self. The 4 way is connected correctly, I know this because the inputs and outputs are lettered on the body and the manual says its installed correctly. I build the piping exactly like in the manual. I guess I should call Taco the head on the 4way is probally bad.

icesailor

Ii wasn't suggesting:

I wasn't suggesting that YOU did anything wrong.

Did you look on the TACO Website for the I=series wiring choices like this one (that probably doesn't cover what you have). They didn't have all these diagrams when I installed them. In fact, I think they were going to dump them. They must have gained in popularity.



http://www.taco-hvac.com/uploads/FileLibrary/IV410.pdf

Here's a link to ALL the wiring diagrams for I series valves. If you haven't seen them. Look at all the diagrams for 4-way valves, only.

http://www.taco-hvac.com/en/products/iSeries%20Mixing%20Valves/products.html?current_category=188#

Drewgrizz

Taco

Also the primary pump is just plugged to power it is set on constant circulation mode setting 1 and constantly circulates the water slowly around the primary loop in and out of the boiler. Boiler fires to keep the water in that loop between 140-180. Then there are closely spaced tee's that run out to the boiler input and boiler return on the 4 way valve. The second pump is a few inches above the system feed on the 4 way and has a system supply sensor a few inches above it that is cable tied to the pipe with pipe insulation around it same with the return sensor. I have the sensors for the 4 way attached at the same spot and the outdoor reset is on the north wall of the house. The system was build all piped and soldered together by a commercial boiler guy in return for me installing an engine in his daughters car(I am a mechanic by trade), I ran all the pex from the manifolds and installed the radiators.

Harvey Ramer

Racket?

Shouldn't be making racket. It should make little ticks, like a clock., when the valve is moving. Make sure your system circulator is pumping in the right direction. Should be on the supply side pumping away from the 4-way valve.



Harvey

icesailor

Primary Side:

Geez, I don't completely understand what you/he did, but the boiler sensor is supposed to stage the boiler. If you have the DIP switch set to the higher boiler protection, and the return water on the secondary is to cold to mix, the return sensor closes the valve and diverts more return water back into the secondary system. As the primary boiler side catches up, more water is diverted back to the boiler. I don't understand how or why you would want it to be constant with a pump that also has temperature control. Then, it seems to me that the closely spaced tee side should be able to also start the primary pump because if the 4-way valve is off and not calling, the paddle in the valve blocks water from going into the secondary side but passes through the boiler. The idea is to have a high flow. If you used this on a beer cooler Mod Con, you might have mis-applied the valve in what you are trying to do.

As far as the clattering of the valve, I found that I usually had to listen carefully to hear the valve " click" when it was modulating. And whatever position it was in, it just "clicked" a degree or two. I never saw a valve wide open.

Drewgrizz

taco

Pump is pumping the right way. The system works fine with the 4way set manually. I did see a wiring diagram on that page that shows the return temp sensor on the primary loop, I might try that instead of putting it on the return leg of the secondary loop.

Rich_49

Wire connx

Sensor wire connections must be over supply when you put the head on the valve also . Check this or your valve will work bass ackwards .

Harvey Ramer

Uhhh ohh.

Yes, most definitely put the return sensor on the return side of the primary loop. It's only purpose is boiler protection.



You see it works this way.

Minimum Boiler Return Temperature (DIP switch 3)

The iSeries-R includes a boiler protection function which prevents low temperatures back to the boiler. Whenever the boiler sensor is installed, the iSeries-R monitors the boiler return temperature and modulates the valve down when the return temperature is near the minimum setting. The minimum setting is selected via DIP switch 3. When the switch is turned on, the minimum temperature is set to 120°F and when the DIP is turned off the minimum temperature is 135°F.

When using low temperature boilers such as condensing or electric, the boiler minimum temperature may be disabled by powering up the control without a boiler return sensor. Whenever the iSeries-R is being modulated towards the closed position to protect the boiler, the green LED flashes rapidly (reduced output).

So with the sensor on the system return the valve would be closing due to the cooler pipes. It thinks it's protecting the boiler and you think you may throw your hammer at it any minute now. Don't throw your hammer, just move the sensor.

Also don't do delta-t pumping anywhere in the system. For example, when the system is calling for heat and the boiler is approaching the low limit, the boiler pump will be going as slow as it can to make sure it is getting the proper delta-t. Now the return sensor from the 4-way says wait a minute! The water going back to the boiler is to cold and shuts down the flow going out to the system.

What do you have now? You have no heat going to the Radiators anymore so that heat will stay in the boiler for a good long while till it cools enough for the boiler to fire, Then the not-so-merry go round starts again.



Don't do delta-t pumping on this system.



Harvey

icesailor

Hummmm,:

Harvey,

This has been rolling around in my aged brain. I'll never be installing it but it is a question.

First of all, I think that the " Series 4-way is the greatest thing to come along for boiler protection and ODR in old systems with lots of water and a big old boiler. Especially on old converted gravity systems with lots of radiators. Pump 130 degree water long enough and all radiators in the system get to 130 degrees.

So, if you connected the 4-way, properly and as designed, and you have two circulators, one for the primary and the other for the secondary, the valve acts as a form of hydraulic separator. When the valve is powered off, the valve closes to the secondary system. When the valve gets a call, both pumps start for operation and protection. If you installed two closely spaced tees on the primary side with a circulator connected to the secondary side (say to an indirect) and it was wired so that only the primary pump and the zone pump came on and NOT the secondary pump on the discharge of the 4-way, and the 4-way head gets no call, does it work? It seems to me that when the 4way has no call, only the primary side will get flow. That as long as any other zone that could call, only starts the primary pump, it just works like any other P/S system. The wiring scheme has to address that. You don't need boiler protection with an indirect because it has so little water in the loop and the boiler heats up so quickly.

Just wondering what you think..

Joe Mattiello

Taco Ivalve, outdoor reset

Good Morning

Lets begin by thanking everyone for having so much knowledge of the Ivalve functionality.  That's cool!!  I'm involved in tech services at Taco, and enjoy talking to people with a good understanding of the vale attributes.  I read through most of this tread, and was impressed with all the feedback on this product. 

You mentioned using the piping diagram found in the instructions sheet.  Which one? I'm assuming primary secondary because of the two pumps.  the boiler protection will minimize flow to the radiant if the water temperature drops below min setting.  

Perhaps you can call me at Taco to discuss your application, and figure out what's going on. 

 http://www.taco-hvac.com/uploads/FileLibrary/102-145.pdf

Drewgrizz

Taco

I would say that the system is built to resemble systems of old just with new twists. I could have sworn the wiring diagram that came wit the 4way showed the boiler sensor on the return leg of the secondary piping. I am going to try to reset the sensors this weekend and see if it works. If not I will call Taco, do you happen to have an extension I can get ahold of you at? I must say though I am glad I fought so hard for this system and didn't stand down and let my contractor install a forced air system. You can not find a cold or hot spot in the house. It is such a consistent warmth, kinda like a perfect spring day. Hydronic heat is the only way to go.

icesailor

Warm Houses:

The first one I installed was on an old two story house with a single gravity system on two floors. It was a pumped system. The radiators closest to the boiler were scalding hot. The farther away, the colder they got.

I installed the valve. The system ran at 125+ degrees in the whole house when it was 15 degrees outside and 68 degrees inside. It balanced perfectly.

If I had an old system with a cast iron boiler, I'd install it instantly. The more water in the system, the better it works.

Harvey Ramer

Ice

Not sure I followed everything there. Sometimes I have the attention span of a goldfish ;-)



If you want to install an indirect with this system, It should be done this way. On the Primary supply line, downstream of the primary circulator, you should put a 3-way diverting valve that is controlled by the indirect. Your indirect supply comes off the 3-way and the indirect return tees into the Primary return.



The T-T from the indirect can be wired directly to the boiler in parallel with the T-T from the system.



Harvey

Harvey Ramer

Joe

I love your responses on here and I like Taco and the I-series.



The only downside I see with the 4-way is the limited flexibility with the minimum and max thresholds. Sometimes it would be nice to set an 85° minimum but no maximum. I have had to leave it out of some designs for this very reason.



Harvey

icesailor

Below Minimums:

Harvey,

I don't understand your comment about not being able to set it below 85 degrees.

I thought the idea behind the I Series 4 way was that the primary/boiler side was to be high for boiler protection and the secondary/system side can be what you want it. If the issue is the ODR sensor, couldn't you get a lower resistor or is the issue that the primary water is too hot and you can't mix down enough?

I don't know why I ask, I'll never see another one. But I like to think about it.

Are you trying to control system temperatures with the boiler return sensor set on the system return side? Wouldn't that set up a conflict with the ODR sensor?

Harvey Ramer

ODR

If you look at the ODR curves on this valve you will notice they all start at 72° on the low end and have a selectable reset ratio that determines the increase in supply temp as the outdoor temp drops. This is fine for a lot of systems but not so great for some emitters that need a higher temperature even when it's mild weather outside, Like base board. They do have one setting that allows the min. supply temp to be set at 85° but then that limits you to a maximum supply temp of 150°. Those parameters just don't fit every retrofit application. I surmise the valve was programed with radiant in mind but with a few simple changes in the programming it could be used in a wider variety of applications. The alternative is a Tekmar setup that costs 3 times as much.



Harvey

icesailor

Taco Technology:

Taco has been in the forefront of some of this technology. They just don't always brag. I'll bet that a chat with them might solve some of that. You can maybe fool it with resisters. I don't know, I'm not an electrical engineer. My engineering is like the Shade Tree Mechanics we talked about when I was younger. I got MY engineering experience in a class with mice and spiders. In a damp, dusty crawl space or a nasty cellar. The mechanic was shaded by the leaves on the tree, I was shaded by the cob webs.

Dave H_2

I-Valve, setpoint or ODR

Drew,



the i-valves can be purchased either with setpoint temperature or outdoor reset. Just clarify which one you have.



Also, did you happen to remove the power head when installing in valve body?

And if you did, do you know if the valve stem was rotated without the motor head?

The reason I ask, is that the head can be mounted on the valve stem only one way, but it can be mounted on the valve posts differently.



You may be rotated 180 degrees.



Also, you probably do not need the boiler return sensor (already piped primary secondary) and that may be limiting the operation of the valve. power down the unit and disconnect the sensor.



Or just call Tech Services at Taco to review your system while you are standing in front of it.



Dave H