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Navien boiler error E302
Low water pressure. System pressure has dropped — often a slow leak or a failed fill valve.
Moderate · you can check this yourself
E302
Meaning: Low water pressure
What causes E302
System pressure has dropped — often a slow leak or a failed fill valve.
What to do
Check the pressure gauge. If it reads under 12 psi, the system needs refilling and leak-checking.
Can I fix it myself?
Often, yes. Try the check below first — it costs nothing and frequently clears the code.
If the code comes back
Book a visit and add the code to the booking. A technician arrives knowing which parts to bring, diagnoses the boiler for a flat $89 and gives you an exact quote before doing any work.
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