Taco Viridian vr15-1

Jay_insula1203

Just finished a job Friday using (5) Taco vr15-1 in the last couple of days 3 of the five pumps have failed one is completely dead and two are flashing code (2) stuck rotor. This is a large hotel and if one more goes down I am in deep doo doo. No heat or hot water, 54 rooms, Heath club, restaurant and employee housing. The pumps only ran for about 4 hours. Any one have any experience with these cirulators ?
I am desperate for any help..............

Gordy

Was system flushed, and dirt mag installed. ECM circs do not like free flowing ferrous materials. That's a lot of failures in a short time on same system.

Jay_insula1203

Thanks - system was well flushed - will take one apart today and check For any debris

Gordy

That would be a first step in finding the issue. Adding a magnetic filter would be a second if ferrous debris is found to be fouling the circs.

Gordy

Steve Thompson hangs out here maybe he will chime in.

Jay_insula1203

Took pump apart checked impeller no debris, put back together had leak, found o ring had broken. $2000.00 pump could have had a little better o ring or extra o ring in box . I am not new at this 41 years in the field.

Gordy

Well, has a taco rep been notified?

I'm quite sure taco would like to get to the bottom of it.
Especially if it is a problem on their end.

Never hurts to check for fouling. Be embarrassing to have that show up with a field rep.

Gordy

Some pics by @hot rod in this discussion.
https://forum.heatinghelp.com/discussion/comment/1365353

It appears the shaft for the impeller collected the ferrous debris.

Jay_insula1203

Thanks for the link to the pictures, when I was on the job site today checking the impeller No fouling and the rotor spun freely. Almost wished for fouling that I could fix, hooked up my laptop and watched the rpm’s starts out at 3000 go to 1650 and then locks out with code (2) stuck rotor. However while I was there one of the other failed cir’s came to life. My chances of making thru the weekend just Doubled.

Gordy

Steve Thompson, and joe mattiello from taco come here maybe they will chime in, or send them a pm.

Tom_133

If you contact your Taco rep they will work with you. They took care of me with a VR20 and it was out of warranty. They are very concerned with us as being satisfied at Taco.

Steve Thompson (Taco)

Sorry for the delay in responding Jay (and thanks Gord for the 'ping" on this post).

3 of 5 failing is a nasty situation for sure to say the least - sorry for this. I assume the VR 15-1's started no problem - how long did they run? By the way these are old models - were replaced with the VR 15-3 around June/July.

As 3 of 5 failed I have to assume (repeat assume) this is a site related issue (not looking for blame - looking for cause / solution). Photos of the rotor would help a lot if available.

ECM sticking rotors are usually caused by iron oxide, "cooked" inhibitors at the sleeve bearings or the outboard bearing running dry caused when the pump is installed with the shaft vertical.

I get the part about the "O-ring" - but at least ours can be disassembled in the field, unlike some of the others. Yes, we could put an extra O-ring in the box but how often is the box saved? The O-ring is rarely damaged but admittedly when it is it's a real pain as it's metric. Sorry about that (we can send you some N/C).

Attached is our exploded view
:
- Remove the head from volute
- Pry the rotor assembly from the #9 rotor can (rotor can should stay in the #14 stator) using a flat blade screwdriver between the bearing plate and rotor can.
- Clean any debris fro the #7 rotor
- Spin the inboard bearing plate (#5) to see if it is free. If not spray some cleaner at the # 6 sleeve bearing and loosen
- Inspect and clean the outboard sleeve bearing for and damage
- Reassemble, making sure the #8 O-Ring is placed between the bearing plate and rotor can
- When reinstalling the head it is critical the impeller eye sit inside the #2 seal ring - otherwise the pump will not run. Our new VR 15-3 manual has detailed instructions on this procedure.

My direct cel number is 401-441-2934 if you have any questions.

One last comment... Flushing the system sounds great but we all need to remember flushing these systems with fresh water that has a lot of air in it actually encourages the formation of iron oxide (rust). Recharging with fresh water with no chemical treatment can actually cause more issues than not flushing at all.

This is true with all ECM circs and pumps with seals, not just Taco's.

Gordy

Thanks Steve very informational. That's support!

Jay_insula1203

Jay_insula1203

Thanks for the input, let’s talk on Monday the pumps only ran for about 3 hours, the one that died completely not showing any lights or error code 2 hours. I am disappointed having just purchased 5 of these pumps to find out they are already Obsolete and that the new model comes with much better detailed manuals

Steve Thompson (Taco)

Agree - give me a call Monday. Is the rotor photo for the dead model or one of the ones that displayed the 2 flash error code? It looks perfectly A OK - did the bearing plate spin freely and did you re-align the heads prior to start-up?

FYI, the new models are identical mechanically. The upgrades are mainly the user interface (cover of the controller) and can be controlled by an external 0-10Vdc or Modbus signal. Spare parts are available as well.

Where were these purchased? Drop me an E mail please at stetho@tacocomfort.com. I have a few more thoughts...

hot_rod

If these are installed on an older system, especially one with a lot of steel or iron, I would highly recommend a good power flush to remove any and all crud. You will need a flush cart or fill bypass able to supply a lot of GPM to flush heavy particles. Determine pipe size and then the GPM required to get at least 5 fps velocity to move crud out.

True when you add fresh fill water you add some air, but it's not air per say but the 20% of O2 in the air. Mostly you are putting nitrogen in with the fill water/ air, @ 78%.

Within a few days that O2 introduced with the fill water will be used or consumed in the oxidation process. That is what turns brand new cast iron volutes red within a few days. Once that small amount of O2 is consumed you have "dead" or O2 free water.

Unless air is entering on a daily basis the corrosion process should stop within days of filling a system.

Personally I feel all ECM circulators should be protected by a magnetic separator in the systems.

Some of the wholesalers I visited recently are insisting mag seps go out the door with ECM purchases. They add them to the quotes. Saves a lot of embarrassing returns, and upset customers they tell me.

Jay_insula1203

Everything was brand new the boilers, (3 Buderus G315/8) piping, one very large spirovent and indirects. We had to build a whole new system while the other one was running because shutting down the DHW system for more than a couple of hours was not a option.

hot_rod

Jay_insula1203 said:

Everything was brand new the boilers, (3 Buderus G315/8) piping, one very large spirovent and indirects. We had to build a whole new system while the other one was running because shutting down the DHW system for more than a couple of hours was not a option.

Then I doubt you have an issue with magnetite seizing the motor, certainly not multiple circs in a short time period. Your pics confirm that. Sounds like a microprocessor or programming glitch.

Paul48

The third picture down..........what is that split?

Gordy

I see that Paul.