termovar solenoid valve

[chuck172]

I'm thinking of installing a solenoid shut-off valve between the balancing ball valve and termovar thermostatic valve. Have it set to close when return boiler temps after the termovar reach 165*
It will stop all flow bypassing the return. In essence it is like automatically shutting the bypass valve when the return hits 165* and the termovar is fully open.
Any thoughts?

 

[Tarmsolo60]

When your return is at 165 isn't your termovar not letting any water through your bypass anyway?

 

[chuck172]

Good question, I thought it still is allowing hot boiler water through. If it closes you're right, no need for any auto valve.

 

[chuck172]

To quote a Tarm sales rep:
"one of the advantages of the loading unit is that port one ultimately closes completely once return water temps exceed 140. With the Termovar mixing VALVE port one is always open at least a little bit so you need to put a half-closed ball valve in the line above port one. "
Seems to me like an automatic valve might do good in this application.

 

[jebatty]

Have it set to close when return boiler temps after the termovar reach 165*

I interpret this to mean that return from the system flowing to the Termovar is 165*. If so, a valve like you describe might be useful. Tests I ran last year with a flowmeter indicate that the Termovar always allows some flow through it from the boiler, even when it is fully open on the system return side. If you have a need for slightly increased system flow when system return is 165* or higher, then the valve may be worth installing. On the other hand, if all your needs are being met when system return is 165* or higher, then you probably are at the point of diminishing returns by adding the valve.

 

[chuck172]

When charging a storage tank and the tank return temp is 160*+, the auto valve would not allow any boiler supply to mix with the return. It would force 100% flow from the bottom of the tank to return to the boiler. I'd say that would have to add efficiency.