Raypak 399B-2339B Water Piping, General, Reversing Water Connections Relief Valve Piping

of not less than 1 in.2 for each 30,000 BTUH mm2 per kW) of total rated input of the burner(s), and the location of the opening(s) shall not interfere with the intended purpose of the opening(s) for ventilation air referred to in (1). This opening(s) can be ducted to a point not more than 18 in. (450

mm) nor less than 6 in. (152 mm) above the floor level. The duct can also “goose neck” through the roof. The duct is preferred to be straight down 18 in. (450 mm) from the floor, but not near piping.

4.Refer to B149 Installation code for additional infor- mation.

Water Piping

General

The heater should be located so that any water leaks will not cause damage to the adjacent area or struc- tures.

CAUTION: This heater requires forced water circulation when the burner is operating. See Table G and Table H for minimum and maximum flow rates and water pump selection. The pump must be interlocked with the heater to prevent heater operation without water circulation.

NOTE: Minimum pipe size for in/out connections is 2 1⁄2 in (2 in. for 399B–899B). Verify proper flow rates and ΔT as instructed in this manual.

5.Remove all plumbing fittings to the header. This will include both inlet and outlet water pipe unions and the pressure relief valve and drain piping.

6.Remove limits, control bulbs and/or thermocou- ples.

7.Remove the six (or 8) flange nuts and the in/out header from the left-hand side.

8.Remove the six (or 8) flange nuts and the return header from the right-hand side.

9.Remove the header stud bolts from each tube sheet.

10.Reverse the headers and stud bolts to the new location.

11.Install NEW red beveled O-rings flush against both tube sheets with the bevel facing outward.

12.Push the header firmly against the O-rings. Install and tighten the flange nuts onto the stud bolts until finger tight.

13.Slowly tighten the flange nuts, starting from the center nut (number 1) in Fig. 9 and working se- quentially around the header as indicated. Torque all nuts to 25 ft/lb. DO NOT OVER-TIGHTEN.

14.Re-route the capillary(s), wiring etc. to the new location, adding thermal paste and shim to the capillary well.

Reversing Water Connections Relief Valve Piping

Follow these instructions to change the water connec- tions from the left-hand side (standard) to the right-hand side.

1.Disconnect all electrical power from the heater (if applicable).

2.Label all electrical connections and conduit lines. This may include the flow switch, low water cut-off probe and/or pump.

3.Disconnect or isolate the main gas pipe from the heater (if applicable).

4.Remove both in/out and return header access panels by removing all sheet metal screws.

WARNING: Pressure relief valve discharge piping must be piped near the floor and close to a drain to eliminate the potential of severe burns. Do not pipe to any area where freezing could occur. Refer to local codes.

Hydrostatic Test

Unlike many types of heaters, this heater does not re- quire hydrostatic testing prior to being placed in operation. The heat exchanger has already been fac- tory-tested and is rated for 160 psi operating pressure. However, Raypak does recommend hydrostatic test- ing of the piping connections to the heater and the rest of the system prior to operation. This is particularly true for hydronic systems using expensive glycol- based anti-freeze. Raypak recommends conducting

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