Taco iseries

nate379

Recently installed a Taco I series reset valve to replace the Honeywell valve.

Problem is with the return bypass closed I get heat to the supply loop but no flow.

I opened the bypass and it heats the house, but then it eliminates the primary/secondary setup so the boiler see ~70* water.

I'd think the setup is correct, it worked fine with the Honeywell, just I wanted a "smart" valve that would adjust the water temps based on outdoor temp.

I had an HVAC contractor look it over and he couldn't figure anything was wrong and suggested to just leave the bypass open.

njtommy

A picture of the piping would help us out.

nate379

Pics

nate379

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I did, is it not loadinf?

Paul S_3

Is the actuator installed correctly looks backwards i may be wrong

nate379

It's correct per the instructions. A is boiler, b is return, c is mix.

Paul S_3

No not the brass valve piping .....the actual actuator can be on backwards....im not 100%

Paul S_3

Are you saying the return to boiler from radiant zone is 70f?is the boiler protection sensor installed?. ...

Tinman

What he is saying is that the head can be mounted on the valve two different ways per instructions. It will only work one way.

Dave H_2

The configuration looks correct as in head position. The terminals on the iValve should be over the boiler supply.

What could be keeping the valve closed is the boiler temperature protection built in. If the return sensor reads below 140F, the valve will close to allow the boiler to get to a higher temperature.

This function can be turned off and then you do not need to install the sensor.

Dave H.

Tinman

@Dave H - could you send me your email so I have your address? sminnich@minnichmech.com

Joe Mattiello

I uploaded the instruction sheet for Taco I-valve which includes orientation instructions synonymous with the 3 way valve. The connection terminals have to be installed over supply side of valve body, and not necessarily A, or B port. The 3 way valve is the only one of 3 body types that position of actuator is critical.
The symptom you’re describing appears like an installation issue. Take a look at how your valve is oriented, and let me know. You can contact me directly at Taco at 401-942-8000; ask for tech support.

STEVEusaPA

nate379 said:

It's correct per the instructions. A is boiler, b is return, c is mix.

When I look at the instructions it looks like B is boiler, A is return, C is mix

nate379

Boiler protection isn't hooked up, was just giving an error, even when mounted on a 180* pipe.

nate379

A or B can be interchanged per the instructions, just the wire end of the actuator needs to be over the boiler supply which it is.


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nate379

It's not an issue with the electron7cs, no postion of the valve when manually turned allows the floor heat to work right unless the return bypass is opened, which then just basically bypasses the mixer.

nate379

As can be seen in the pics the supply and return Ts on the primary loop are several feet of pipe from each other. The return has a swing type check valve.

Now this did work ok with a Honeywell MX series valve, just I didn't like the set 130* water whether it was -20* or 50* outside.

Harvey Ramer

Can you draw a diagram of your piping layout with flow direction arrows?

nate379

Yup, I did, just trying to get my 20 year scanner to work with the new Windows.

Tinman

Thanks Harvey. I was really trying hard to see what goes where with no luck.

4Johnpipe

Make sure the insulation is not between sensor (underside of I valve) and pipe...although I think the sensor is closer to the union nut.

nate379

This is the simple version, hope it makes sense. I've got a 102* fever and been sick since Sunday. I forgot to draw in all the ball valves, but they don't really matter. There is one on the return bypass that is normally closed, everything else is open. The whole system worked fine before the i Series valve.

nate379

Wanted to mention to that I have always wondered if the supply and return Ts off the primary were ok being several feet of pipe away. Does the pump on the primary make that fine?

I had an HVAC guy look it over and he couldn't find any fault on why it wasn't working right.

aldefed

I have a 3 way I-series valve that I use to mix down my primary boiler loop for my radiant. On my setup, I have a set of closely spaced tees for the supply to the mixing valve and the return from the mixing valve. The closely spaced tees allow the primary loop to be maintained at the higher temperature of the boiler and then the I series draws just enough of that water to bring the radiant loop return back up to setpoint and the rest of the return water goes back into the primary loop.

Paul S_3

The return bypass valve must be open you will never move water out of radiant zone ....i see no primary /secondary....you need closely spaced tees on the primary loop

Joe Mattiello

did it work???

nate379

The valve wiring/actuator isn't the issue. I'm wondering now though if I should have used a 4 way valve and not 3?

Quite pointless to try to regulate mix temp if the return is coming back with no regulation. The bypass was never open with the 3 way Honeywell MX valve.

Not sure why the Ts are so far, I'm not an HVAC contractor and one that has put in hundreds of floor heat systems for the builder of my house set it up. My neighbors was done pretty much the same too and I'm sure many others. I can replumb if it's a problem.

Tinman

Not intended to frustrate you more, but I installed my first iSeries 3 way valve last week and it's working flawlessly. I'll be using them a lot going forward. Have you tried "Find a Contractor" on this site?

aldefed

The I-series is regulating your supply temperature to the radiant loops. Your return temp is going to be based on the flow thru your radiant. My boiler primary loop runs between 160 and 180 degrees. My radiant runs around 80 degrees when it is 30 degrees outside. I adjusted the flow thru my radiant so I would have a 10 degree drop in water temperature. At this point, the I series will draw in enough of the primary loop water to bring the radiant return water back up to its setpoint. The remaining radiant return water will then go back into the primary loop to be reheated. You need the closely spaced tee's so the primary loop and secondary loop are hydraulically separated from one another. I've been using my I series for about 3 years and it works perfectly. There must be a fundamental difference in the way your old valve regulated the water temperature.

nate379

You have the return bypass wide open?

The zones are all max flow, about 2+ gpm. I've only changed the valve.

aldefed

My return is open. It has to be open for the radiant return water to be put back into the primary loop to be reheated. You need the closely spaced Tees so the primary pump and loop acts as a separate entity from the secondary pump and loop.

nate379

Ts on suction or pressure side of the circulator or does it matter? *ie* which t do I move?

Dave H_2

Nate,

The "return bypass" needs to be open.

I have to ask a simple question, it may be simple, maybe I didn't see read it properly;

Are you heating the room(s) to desired setpoint?

It looks like it should be doing a fine job piping and wiring-wise, so what is the main problem that you are experiencing?

Dave H.

BrianPhilly

I can't see how this setup possibly works with the bypass closed.

Suspect that the new valve flows more water than the old one and that's the root of your problem. Have you tried throttling the bypass?

Harvey Ramer

Here's your problem Nate.

In the diagram you drew, the point of no pressure change is in the primary loop between the supply and return to the radiant, on the one side if you will. The pump on the primary loop could also be considered between the radiant supply and return on the other side of the primary loop. The boiler has very little pressure drop, it could be taken out of the loop for the sake of analysis. The will pump create a pressure differential across it in order to move water. The pressure differential that the pump creates can only be equalized through the resistance of water flowing through the pipes or components. At the expansion tank location, the pressure cannot change. What this is doing is exposing the cold inlet and hot inlet of the 3-way valve to the pressure differential of the primary pump. It cannot work properly this way. You must move, "what you have labeled the return bypass" to a location just downstream of the radiant supply tee on the primary loop (closely spaced tees).

Paul48

With the bypass closed, you have no return to the primary loop. Closely spaced tees are on a common pipe, not one on a supply and one on a return in close proximity to each other.

nate379

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Dave H,
No heat to the floor.

nate379

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Harvey,

So the return goes to the I series as well as the primary?
I call it a bypass since that's what I was told it was. It's never been used before. The heating system worked fine since install in 2009. (I say fine I mean the house was heated)
I don't know the how or why, I'm not the person that set it up. The company that, Hard ROK plumbing did has no record of it, different owner at the time.

Either way I'll move it around in the next few days or so. Trying to remodel another house as well as finish logging (my real job) a parcel with an upcoming deadline.

Harvey Ramer

Nate,
The way you have drawn the diagram, if what you call the return bypass, is closed, it is 100% impossible for the floor to get any heat other than what the pump motor produces.
Are you certain your drawing is accurate showing all pipes?

nate379

With the bypass closed it returns to the i series valve. Yup the drawing is correct.

I can only guess that the big Honeywall valve worked differently. It had hot, cold and mix. hot from the boiler, cold was the return and mix the supply to the floor.

nate379

Working on fixing it, just need to wait till Monday for parts, Lowe's doesn't carry 1.25 pipe and a need a small piece and some couplers.