Even if there are pumps in the box, their energy draw is not subtracted from the COP, making those advertised numbers bigger.
From Wikipedia: "ASHRAE transitioned to ISO 13256-1 in 2001, which replaces ARI 320, 325 and 330. The new ISO standard produces slightly higher ratings because it no longer budgets any electricity for water pumps."
Rough example: At 600w per ton of capacity for the compressor power alone (should be this or less), 4 tons is 2400w. If we lose maybe 40 feet of head pumping 10gpm through the heat exchanger, 50' each way of 1" piping to the loop field, and the loop piping, plus lift the water 100ft (open system) the pump will take about 350w, assuming 90% motor efficiency and 78% pump efficiency. That drops our "rated" efficiency almost 15%. Since the heat pump efficiency will go up and the water pump efficiency will go down at lower loadings, the actual efficiency will be affected by the pump draw by a much larger percentage at lower loadings.
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"I‘d put my money on the sun and solar energy. What a source of power! I hope we don‘t have to
wait until oil and coal run out before we tackle that." Thomas Edison, 1847 — 1931
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