This document describes a flow modulated 330 PN indoor model suitable for heating potable water only. It is not approved for space heating purposes. The product is intended for variable flow applications with steady cold water inlet temperatures.
This manual provides step‑by‑step installation instructions, safety warnings, and required clearances for the Bosch 330 PN indoor water heater. It also covers gas‑type selection, venting requirements, and recommended combustion‑air provisions.
Additional sections describe operation, maintenance, troubleshooting, and warranty information to help installers and owners keep the heater running safely and efficiently.
| Capacity | 2.6 GPM |
|---|---|
| Maximum output | 58 400 Btu/hr |
| Maximum input | 74 900 Btu/hr |
| Recovery efficiency | 78 % |
| Minimum output | 23 906 Btu/hr |
| Gas connection size | 2 inches NPT |
| Vent diameter | 4 inches |
| Minimum vent height | 6 ft (no elbows) |
| Water connections | 2 inches NPT (hot and cold) |
| Minimum water flow | 0.5 gallon/minute |
| Minimum water pressure | 13 PSI (0.9 bar) |
| Weight | 26 lb (12 kg) |
Close the gas valve, open windows, avoid any electrical switches or phones, and call your gas supplier from a neighbor’s phone; if you cannot reach them, call the fire department.
The vent pipe must be at least 6 feet high when installed with no elbows.
The heater delivers a capacity of 2.6 gallons per minute.
Natural gas inlet pressure must be between 5.7 and 14 inches water column.