
Balboa Heater O-Ring 2", 21619
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Quick overview
- Balboa part 21619 The o-ring listed by Balboa Instruments as the 2 inch heater o-ring.
- Two inch size Sized for the 2 inch heater connection, not the smaller unions on the same pack.
- Seals the joint It is the soft seal that keeps water inside the heater connection under pump pressure.
- Cheap insurance Rubber flattens and cracks with heat and age, and a new ring costs far less than chasing a leak.
- Replace on service Worth fitting whenever the heater is opened up rather than reusing a set ring.
- Fit it clean Wipe the groove out and seat the ring dry or with a silicone lubricant, never petroleum grease.
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Balboa Heater O-Ring 2", 21619
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Product details
The Balboa 21619 is the 2 inch heater o-ring, the soft seal at a Balboa heater connection. It is a small part with an outsized job, since it is the only thing holding water inside the joint once the pump is running.
When to change it
Any weep or drip at the heater connection points at the o-ring first. Heat cycles harden the rubber and the ring takes a permanent set in its groove, so an old ring that has been disturbed rarely reseals. Fit a new one whenever the heater has been opened up.
Fitting
Wipe the groove and the mating face clean before the ring goes in, and check that nothing has been nicked. If you lubricate it, use a silicone based lubricant, since petroleum products attack o-ring rubber.
| Brand | Balboa |
|---|---|
| Manufacturer part number | 21619 |
| Type | Heater o-ring |
| Size | 2 in. |
| Application | Heater connection seal |
| Ships | Parcel |
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