Boiler protection with Danfoss ESBE TV and balancing valve?

[kuribo]

Is anyone using the Danfoss three way thermostatic valve with a balancing valve for boiler protection? Seems compared to an actuator driven, three way mixing valve and controller, it would be a much less complicated and expensive solution, as well as not requiring power.

Anyone with experience with these? I am looking at the 1-1/2" model.

(broken link removed to http://www.danfoss.com/North_America/BusinessAreas/Heating/Products/Detail/HE/Pressure-and-Flow-Controllers/STV-Series-Balancing-Valves/065F8969/e55bb592-7a71-42e2-ae88-dfc80f288734/09241fa8-ac49-4212-97eb-a5b5203bef45.html)

(broken link removed to http://www.danfoss.com/North_America/BusinessAreas/Heating/Products/Detail/HE/ESBE-Valves-and-Actuators/Thermostatic-Boiler-Protection-Valve/Boiler-Protection-Applications-TV/065B8925/b5b9b5cc-ae87-40a4-83f3-b9b8524e4bd6/4109bd44-0f10-4da1-a0b2-c71e04515a70.html)

 

[goosegunner]

I have the TV valve, it works ok but never really stops the flow from the hot port.

From talking with the DanFoss rep the VTC valve stops the flow completely from the hot port. I would read up on the the VTC valve and probably purchase one of those if I was shopping.

gg

 

[Blue Tornado]

Looking at the VTC installation instructions: What the heck does it say to a layman?

 

[kuribo]

Hmm, they don't make a VTC in the size I need, 1-1/2"....So the TV continues to have some bypass flow past the thermostat set point?

 

[arngnick]

I agree with goosegunner I had the same expirience when I ran a boiler with a Danfoss valve. My boiler would get up to temperature and my storage was very slow to gain heat. I had a valve on the hot water port so I could throttle the hot water and allow better flow, but if you close to much hot water off and your return water is too cold it will stop the flow.

On my new unit I am using a loading valve and it works great!

 

[goosegunner]

From what I remember the pressure drop on the 1-1/4" VTC was not very high. I think it's ability to close the hot port completely might be worth it.

gg

 

[kuribo]

Just to be sure I understand the problem, you would get ghost flow back into the boiler from the hot port, or would the valve never fully close the return leg so that there would always be some flow back through the boiler, rather than it all going to the tank when the return water was above 140F?

 

[goosegunner]

Just to be sure I understand the problem, you would get ghost flow back into the boiler from the hot port, or would the valve never fully close the return leg so that there would always be some flow back through the boiler, rather than it all going to the tank when the return water was above 140F?

Exactly, The TV valve will continue to flow through the hot port when the water is above 140. The VTC will adjust until it is completely closed so all the flow will go directly to the storage tank.

gg

 

[kuribo]

That is too bad....I really liked the simplicity of it....Don't think the VTC won't work for me, the Cv is a lot smaller.

Guess I will have to give some thought to an actuator driven mix valve. Was hoping to avoid the added complexity and expense.

 

[kuribo]

Just talked to Danfoss and they are no longer selling the TV valve; it has been replaced by the VTC...

But I also found that an EU company called Regulus makes Thermostatic valves for boiler protection in 1-1/2" and 2" sizes with nice Cv's! I don't know what they are charging for shipping to the US, or the quality, but their prices are much less than those in the US. Anyone have any experience with this company or their products?

 

[Trex83]

Not really responding to your last question Kuribo, but Caleffi or Termoventiler (Laddomat) may provide you another option.
When you factor in the cost of buying the circ pump, temp gauges, ball valves and getting a well made component that reduce chance of not plumbing it right (little circles and triangles for hot/cold/mix...) is well worth the money. Actually my father calculated the costs and its pretty close to buying the parts separately.

Not familiar with the company you mentioned.

My dad uses the VTC with no problem (order the correct thermostat pin for the correct configuration - we had issues with a higher temperature thermostat element). But its only in 5/4" or 1" NPT.

Good luck
Trex