Global affect of Pressure differential pumps *~/:)

Weezbo

Ok . just how much energy savings can be accrued to the useage,to date?

is there a study of the balance in that energy savings account?

When do we have one in the shop? on the truck ,in the van ,on the boiler?

what is the News on small residential circs?

Brad White_124

I see them as

effective as a control mechanism more than an energy saver.

If you have 4,380 heating hours (half the year just a guess, Alaska may vary ) and your circulator uses 65 Watts, that is 284.7 kWH. At $0.15 (15 cents per as we seem to be paying these days), that is $42.70 per year.

Depending on your system curve and what you have for TRV's (if you do not have them, why use DP?), will you cut that in half? Two-thirds? And for how many hours of the year? (And if you need to trim down that much on average, are you not over-pumping in the first place?)

A Grundfos 15-42 VS I have seen in the range of $400 to $500 compared to a 15-58 at about $80 to $100. A premium of $300 to $400 against a potential savings of $20 is a 15 to 20 year payback.

I have no idea what an Alpha or Armstrong DP circulator goes for. Of course with the Grundfos or any VS circulators, if the control is not built in, you have to install a DP transducer for maybe $150 on top of the circulator.

I would use them for smooth control more than anything. I am speaking of variable speed circulators in general, not just DP applications but for injection pumping too.

BUT, as so often is the case, others have more hands-on experience, so I will sit back...

My $0.02

Brad