Water source heat pump installation open loop or closed loop?

Open loop vs. Closed loop

In initial meetings, many of our customers have stated that open loop systems are more efficient than closed loop systems. In most cases they’ve heard this from another contractor. This statement is misleading and doesn’t apply to operating costs. I’d argue that generally speaking both systems are equally efficient. The most important factor is which one is the best fit for you. Let’s take a look at both…

“Open loop” and “closed loop” refers to the source.  The source side is the location where the heat pump will be extracting or rejecting heat to.  The load side is the home we’re trying to heat or cool. Let’s start by looking at the pros and cons for each geothermal source. Remember that efficiency for ALL water source heat pumps exceed that of any other heating system today:

Open Loop Source (“pump & dump” or “once-through”):

Refers to running domestic well water through the system and discharging somewhere

Pros:                                                                                     Cons:

Less expensive install costs                                           Increased well pump usage

(In most cases )                                                          Water quality concerns

Consistent entering water temperature                            Additional water control valve required

Slightly more capacity in late winter                               Discharge water location / design required

Closed Loop Source (Horizontal pit or trench, vertical bore, horizontal bore):

Refers to circulating the fluid out through the ground and back through the heat pump in a continuous loop with high density PE pipe

Pros:                                                                               Cons:

Control over water / brine quality                     Typically higher initial install costs

No scaling or build-up concern                        Requires yard space

Less maintenance                                            Lower entering water temperatures (heating)

Zero water usage from well

Zero Energy Consumption from well pump

2018-06-18T14:43:57+08:00Categories: Knowledge base|