Vitodens 200 control

Steve_56

I'm working with a contractor to design/install a retrofit hydronic system. Original design spec'ed out MZ boiler with Tekmar 363 controller, one baseboard heating zone (6+ loops), one radiant floor heating zone (8+ loops). The house is big (~4000 sf), and there will be at least a couple loops serving areas that are rarely used.

After doing a bunch of reading, I'm leaning towards the Vitodens 200 (8-32) instead. I also want to allow for future addition of DHW and (supplemental) pool heating.

Since the Vitodens already has some degree of control (Outdoor Reset, DHW priority), what, if any, additional controls do I need? My concern is, although the Vitodens is a great boiler, the control functions offered by Tekmar seem far more flexible. For instance, there doesn't seem to be a DHW purge feature.

I'm still waiting to hear back from my heating contractor, but any additional feedback would be great.


Thanks!

marc

dhw purge

not any mass to the vitodens, so nothing to post purge. marc

Paul Pollets

Comparison

The Vitodens is easier to wire (true plug n play)and offers considerably more control over the system with a "smart" pump. First time users, without having taken the Viessmann training, will probably have some difficulty. A better boiler, installed improperly, does not make for a better system. What is the contractor familiar with? Is he choosing the equipment or you?

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S Ebels

Also

You can program the Vito to do either of these whilst producing DHW.

It can be programmed to ramp up to max temp and stay there while heating OR........

It can be programmed to maintain a diferential setpoint that tracks the DHW temp and boiler temp so they go up together. Usually this is 20 * differential.

Unknown

Comfortrol

More control with the Comfortrol than with Tekmar's. IMO It's a system aproach. Think about the whole house and ask your control to self adjust. That's what the Comfortrol does.
Post purging a vitodens is useless. Not much heat there to scavange. As Paul said, " easy to wire." Contractor must have at least some technology based training to install. Or you will recieve what we call a (bait & Switch) The nameplate rating means nothing. It's all about the installer and his ability to get that machine to condense.

By the way, I think you can't go wrong with the Vitodens. Make sure the installer has been through some factory specific training & you can't go wrong.

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Steve_56

Vitodens 200

I hired a contractor to do the heat loss calcs and put together system design info for a do-it-yourselfer (me). They will be providing oversight and will be there when I turn the system on.

They also gave me a package price for all the system components. After some shopping, I found out they were tacking on about 90% to the retail price for this stuff. While I understand warehousing some of this stuff is worth a premium... it's hard to justify ~$8000 worth...

The contractor recommended the MZ, told me the Vitodens was better, but twice as much, and the way they price things, I'm sure that's about right. But I found a distributor that sells the Vitodens and it's not much more than the MZ, so it seemed worth the extra bucks. So I'm working on them to re-work the system design around the Vitodens, but wanted to get other ideas.

Steve_56

Vitodens controls

Well, as you may have seen, I'd like to install this myself. Although cost savings is part of the issue, the biggest reason is to fully understand how the system works. Do you think this is a bad idea? FWIW, I've been studying this online for awhile, and have ordered Dan's book as well (hope it helps).

So it's good to know the DHW purge is non-issue.

And it sounds like everyone recommends setting up the Vitodens as described in the application notes with the add-ons for DHW and outdoor reset for the mixed zone.

That leaves me with two questions.

1) How do I add the zone for the supplemental pool heating (I'll look at the app notes again for this one)
2) Maybe a dumb question, but since both the radiator zone and radiant floor zones have multiple loops with multiple thermostats, is there a controller to help coordinate this? Or is the outdoor reset along with loop static flow control usually adequate?

Thanks again, Steve

Constantin

Steve...

...as a fellow enthousiastic homeowner, I have been doing a lot of online reading myself, yet I would not attempt to install a piece of equipment like the Vitodens without the factory training that goes with it. Viessmanns are designed to keep untrained personell from starting them (lockout). Not just Cisco knows a thing or two about proprietary codes...

From my reading here and elsewhere, it appears as though your plumber will have his cake and eat it too: He'll make plenty of money from the equipment sales, yet have none of the responsibilities that go with the job. I cannot think of a better way to expose yourself to a very unhappy ending.

This is not to say that you won't succeed. However, have you tried "Find a Professional" yet? After all, a number of them on the Wall have been happy to let homeowners muck around with the parts of the system installs they don't enjoy, while saving money, aggravation, etc.

Glen

controls -

The vitodens is capable of many things - depending on your control strategy. It sounds like you will need at least two four way mixing valves (Viessmann)to supply your downstream mixed temperatures as well as the DHW kit to supply DHW. Talk to you local Viessmann sales rep (Rhode Island?) to ensure/confirm that what you getting is what you need. Knowledge of the programming capabilities is essential for your immediate and continued happiness. My preference is to control room temps with the Heatlink Statlink system and let the Comfortrol do everything else - it is afterall - completely ODS based - and fires the boiler when it thinks it should. Interestingly - there is no physical communication between a call for heat in your living room for instance - and the boiler. After the plug and play previously mentioned and the programming by your Viessmann guru - you can sit back and watch the blinking lights - with warmth on your toes and a smile on your face.

LanceR

Vitodens vs. MZ

Hi Steve,

I'm also a homeowner trying to decide between a Vitodens, an MZ, and a Munchkin. Vitodens are few and far between here in Utah but the engineering of the boiler seems excellent. The new Buderus GB142 is also interesting although I am not sure if they are shipping yet. I'd like to get your opinion about the various boilers. If you don't mind sharing your views, email me at rangerblacklab@comcast.net

Without "The Wall," I wouldn't even know about these boilers.

Thanks!

Lance

Mike T., Swampeast MO

Comfortrol is Aptly Named

Just set up my first Vitodens to a TRVd system. With TRVs set at normal levels and an outside temp in the low 50s and with factory settings I have to crank the room temperature dial to get the boiler to run.

Then it starts at full fire, rapidly ramps down, I hear some water going through the differential pressure bypass, the supply piping (black iron) is hot "spooky fast" and then the burner shuts down after hitting the wildly inflated (because of the high setting on the room temp dial) supply target. All in around one minute! I even have some small radiant floor zones with no form of flow or temperature control so there is still some system circulation even with all the TRVs satisfied! It does this without ANY connected sensor for inside temperature!

It's smart enough to essentially tell me that if I REALLY want heat, I'll have to turn up the TRVs!

Steve_56

StatLink

Thanks Glen,

I'd never heard of StatLink before, but that solves the individual loop control issue. Are there comparable products I should be looking at as well? Also, do you recommend the Heatlink manifolds in this case?

So if I understand correctly, instead of trying to (statically) set the flow rate in each loop based on heat loss calcs for each room, this system, with the PWM output, will dynamically adjust that flow.

So, to really make this the perfect system, is there a way to simply have a temp sensor in each room, then do all the thermostat PWM output based on that temp in the boiler room? I'm trying to put together a "smart-home" system where the thermostat settings for each room are controllable from a master panel (computer), as well as from each room (probably via a remote computer interface).

Thanks for the info!

Mike T., Swampeast MO

Danfoss FHVs...

..offer the same loop flow balancing provision integrated with true proportional control of the space temperature. The Vitodens LOVES spaces with proportional control...

If you use the thermostatic operators that offer electric setback ability on the FHVs you can develop your own FAIL-SAFE setback sceme using common, inexpensive components and low voltage--it can be as sophisticated or as simple as your budget and ability allow. With some decent computer knowledge, you can easily use a parallel port to drive a relay panel to completely automate the setback. Similar commercial systems will cost an utter fortune.

Glen

heatlink

Have a look at this site. I'm not sure if the remote night set back and other options are yet fully marketed for the Statlink. the viessmann can have a remote Comfortrol installed in the home - so you don't have to go to the boiler room to see whats what.

http://www.heatlink.com/caen/index.htm

Flows still need to be tweeked at the manifold - but after that - its all down hill. Yes - I really prefer the heatlink manifolds. My only beef is that they supply too little silicone grease to properly lube all the o rings. I have used most from the major suppliers - even made my own - the heatlink product is made very well.