Flow Thru Heaters

When selecting a replacement flo-thru heater assembly for a discontinued one, there are three important measurements
to keep in mind:

         1. Length of the housing
         2. The distance from LEADING END to element connection
         3. The pressure switch location
Note: Measurements 2 and 3 are typically in a fixed position if the heater is installed inside a box.

New holes can be drilled in the box if the heater mounting studs are not a match.
The location of the sensor bulb is not critical.

Additionally, you must consider the wattage of the element. Select the same wattage whenever possible. If same wattage is not available select a lesser, not more, wattage unless you're sure the system and electrical service is capable of handling the additional amperage.