pump setpoint control

[chuck172]

I'm looking into a pump Difference Setpoint Control. The Tekmar 157 would fit the bill but @ $250. I'm hesitant (cheap).
Has anyone found other off the shelf solar controls that are less expensive?

 

[RobC]

What are you going to use it for ? May be there is another way to control ?

 

[ewdudley]

I'm looking into a pump Difference Setpoint Control. The Tekmar 157 would fit the bill but @ $250. I'm hesitant (cheap).
Has anyone found other off the shelf solar controls that are less expensive?

[Edit: These are mostly bang-bang relay controls, looks like OP needs variable speed.]

Has anyone tried any of these?

http://www.mydtcstore.com/

Fullgauge has some well engineered down-market differential controllers if you can find a retailer:

http://www.fullgauge.com/index.asp

--ewd

 

[chuck172]

I'm looking to throttle the boiler supply water (taco 007 pump) to the storage tank. I'm doing it manually now with a motor speed controller but I'd like to automate .
With usb temp. sensors all over my system I'm finding out what a big difference this can be.

 

[chuck172]

the mydtstore looks interesting. Wonder if it would throttle a taco pump. I emailed the seller. thanks.

 

[Pat53]

I'm looking to throttle the boiler supply water (taco 007 pump) to the storage tank. I'm doing it manually now with a motor speed controller but I'd like to automate .
With usb temp. sensors all over my system I'm finding out what a big difference this can be.

Chuck, here is a link to a Taco 007 VDT pump. Only 215.00 w/free shipping. Now, supposedly you can configure a VDT pump to work as a Setpoint circulator, at least thats what one of the tech's at Taco told me. I have an 0014 VDT I'm going to try as a Setpoint pump in a week or so.

http://www.sdsmarket.com/Taco_007_VDTF5_Variable_Speed_Delta_T_Circulator_p/007-vdtf5.htm

Pat

 

[chuck172]

Great price on that pump Pat, thanks.

 

[Pat53]

Great price on that pump Pat, thanks.

Sure, no problem, they have the best prices I've found on the web for the Taco VDT pumps.

Pat

 

[ewdudley]

the mydtstore looks interesting. Wonder if it would throttle a taco pump. I emailed the seller. thanks.

Sorry, those are multi-second PWM relay controls.

Looks like you want variable speed. The Taco VDT at $215 below would be hard to beat, but configuring one for single setpoint control hasn't been demonstrated that I know of.

But if you already have a pump and don't want to bundle in another, you could do it on-the-cheap with a $79 Nimbus fan control. Smokelessheat.com, for one, is retailing them.

The generally available version is for fan control and has DIP switch selectable setpoints only up to 114 degF, so you'd have to add some resistance in series with the sensor to fake the controller into seeing a lower temperature in order to use it for hydronic temperatures, which would take some bench time to perfect.

--ewd