# Picking a flow center

Discussion in 'Geothermal Loops' started by TowPro, Mar 13, 2013.

1. ### TowProMember

I am looking at the climatemaster tranquility 30 digital series TE026.

loop will be a well that is 75 feet distance (level) from the flow center, somewhere between 300-400 foot deep, single loop of 1.25" pipe.
(depth is unknown at this point, The well already exists, but if I need to add depth, I will have driller add max depth for the "min cost involved to bring well truck on site".)

I like the idea of the internal flow center because the advertisements say "vFlow™ systems reduce water pumping power consumption by
60-80% compared to traditional external pumping modules, which can save over \$100 per year in an average 2,000 square foot home"
Plus I like the way I can set for temp delta in thermostat and system runs pump at speed required to give me that delta.

I am also looking at a single pump QT flow center which has an advantage of me not needing a flush cart. (but I have to be willing to run Propylene Glycol antifreeze).

A salesman said the vFlow runs around 70 watts max.
The QT runs at 1 amp @ 220V = 220 watts.
So I want to figure out how much more the QT will cost to run. (please check my math).
220 watts (QT) - 70 watts (vflow) = 150 watts difference which is .150 Kw running for 1 hour would be .150 kwh.

Now GeoDesigner shows the 027 in my house will run 1,828 hours for heat and 547 for cool = 2375 total hours run time.
2375 hours x .150 Kwh = 356.2 Kwh x .13 cents per Kwh = \$46.31 more money per year to run the QT.

Now I understand this calculation is based on the vFlow running at 100% load, but I think I will only see 100% loads during peak heating and cooling seasons so I guess this calculation is flawed.

If the internal flow center cost \$463.10, more then the QT, then my payback is 10 years.
Is it worth it? (I don't know the price difference yet, but I will tomorrow).

2. ### waterpirateWell-Known MemberIndustry ProfessionalForum Leader

If you are going to use the CM digital I would be inclined to not " cheap out now " and pay the extra for the vspeed internal circ designed for operation with that unit. JMHO
Eric

3. ### TowProMember

It turns out the vFlow system is \$100 more then the QT system, but I wasn't thinking of this as "cheeping out", I was weighing the advantages of both flow centers.
I guess I will be building a "Personal flush cart". Maybe using the pump they are pulling out of my well. I have a 220V outlet right next to the flow center location.

4. ### waterpirateWell-Known MemberIndustry ProfessionalForum Leader

By cheaping out, I was refering to the design. In my mind once you get to the digital unit, not useing a varaible speed pump controled by the units wants and needs is folly. A word of caution about useing submersible pumps for pumping applications other than in wells. A submersible pumps motor depends on the continuos flow of water accrossed the motor for cooling. Without that cooling, the motor will quickly generate enough heat to trip the internal heat switch and stop the motor. You will need to install a shroud to make the water directional for cooling.
Eric

5. ### TowProMember

Thanks for the tip on the well pump. I been looking at another 1.5HP pump I could use that is not water cooled.
Its a shame, just last summer I threw out a swimming pool pump that would have been perfect.

6. ### waterpirateWell-Known MemberIndustry ProfessionalForum Leader

I really really hate when that happens. I guess that is why I am the only person who thinks the reclaimed rig parts in the yard are treasures not trash. lol
Eric

7. ### Mark CustisNot soon.Industry ProfessionalForum Leader

I never throw anything away according to Stephanie.

Mark

I think thats the motto of every driller Ive ever met! LOL
Nothing worse than a water swivel or similiar breaking and not being able to run to your local plumbing supply house for a quick replacement when you got 300' of drill rod in the ground.!!!

9. ### docjenserWell-Known MemberIndustry ProfessionalForum Leader

I prefer an external flowcenter than one which is built in the heatpump. However, I also think that delta T controllers have a future.

10. ### CainMember

pump question ECM or not

I am looking at 3ton Geologix and WaterFurnace. both quotes state the units have inteligent controls. does this mean i will need an ECM type flow center to make the most of my HP.
Have been quoted a QT1-230 qfc to pump through 3 600' circuits with header in basement. does that seem like enough/correct pump?