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- Remove drain plug from header and allow all water to drain from heat exchanger.
Locate the threaded boss on the outlet port of the header, and find the dimple at the center.
Use the dimple to center the drill bit. For header type A: Drill a 1/4 in (6.4 mm) diameter hole through the boss. For header type B: Drill a 3/8 in (9.5 mm) diameter hole through the boss. Take care not to damage the plastic threads. TIP: Drilling a 1/8 in (3 mm) diameter hole first will help prevent thread damage.
- Each male connection should be first wrapped in 5-6 turns of PTFE (Teflon) tape.
- Install the temperature sensor assembled with any required reducers at the heater header. Make sure to get a snug fit. Do not over-tighten.
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