Document LTP0101 rev 2.1f

 

Adjusting Water Flow Using ΔT (Delta-T)

The Delta-T is the temperature difference between the water temperatures entering and leaving the heat pump. The equipment can be fine-tuned for maximum performance by balancing water flow rates to maintain an ideal ∆T.

  • Installed temperature ports are required to perform the following procedures.
  • These ports are typically located on the pool in and pool out water lines approximately six inches away from the heat pump.
  • The adjustment procedure must be completed with the unit in heating mode.

Please Note -

Temperature Port

(Shown with Probe)

  1. Adjust thermostat to its lowest setting with unit in heating mode.
  2. Deactivate the water filtration pump.
  3. Confirm that the filters leading to the heat pump are clean.
  4. Adjust the valves controlling water headed towards the heat pump to the half open position.
  5. Adjust the valves controlling water leading away from the heat pump to a fully open position.
  6. Activate the pool water filtration pump.
  7. Slowly raise the thermostat temperature until the heat pump activates.
    • The source-water filtration pump will cycle on first.
    • After a four-minute delay, the heat pump's compressor will start.
  8. With the heat pump running, confirm the source-side water filtration pump is operating properly with adequate flow and no short cycling.
  9. Wait for water temperatures to stabilize (approximately 5 minutes).
  10. Adjust valves in the following order using the temperature chart provided:
    1. Adjust the source-side valve on the heat pump outlet until the correct temperature differential is achieved.
    2. Adjust the pool-side valve that controls water exiting the heat pump. Match the temperature measured with a temperature probe to the chart.
    3. Wait for water temperatures to stabilize. Then check source-side temperature again. Re-adjust the valve as needed.
    4. Wait for water temperatures to stabilize. Then check pool-side temperature again. Re-adjust the valve as needed.
  11. Mark valves at these positions for future reference.
Table 1 - Temperature Chart
HEAT EXCHANGER TYPE MODEL POOL-SIDE SOURCE-SIDE
Titanium pool-side and source-side exchangers WS03 2° to 4° F 1° to 5° F
WS05 3° to 6° F 2° to 8° F
WS10 6° to 14° F 5° to 12° F
Titanium pool-side exchanger and cupronickel source-side exchanger WS03 1° to 3° F 6° to 8° F
WS05 2° to 6° F 7° to 13° F
WS10
 6° to 14° F 6° to 11° F

 

Table 2 - Temperature Chart (Sun Power)
HEAT EXCHANGER TYPE MODEL SPA-SIDE SOURCE-SIDE
Titanium ThermoLink® SP05 3° to 6° F 2° to 8° F

 

Please note -