Xylem MM 219J Replacement Head Mechanism User Manual download pdf

INSTRUCTION MANUAL

MM-219J

Replacement Head Mechanism

Replacement head mechanisms can be installed without

disturbing existing equalizing connections or disassembly

of components, making repair simple and easy.

Replacement Head Mechanism

Snap Switch

Models:

150S-HD

150S-M-HD

150S-MD-HD

150S-M-MD-HD

158S-HD

158S-M-HD

158S-MD-HD

158S-M-MD-HD

159S-HD

• Before using this product read and understand instructions.

• Save these instructions for future reference.

• All work must be performed by qualified personnel trained in the proper application, instal-

lation, and maintenance of plumbing, steam, and electrical equipment and/or systems in

accordance with all applicable codes and ordinances.

• To prevent serious burns, the boiler must be cooled to 80˚F (27˚C) and the pressure must be

0 psi (0 bar) before servicing.

• To prevent electrical shock, turn off the electrical power before making electrical connections.

• This low water cut-off must be installed in series with all other limit and operating controls

installed on the boiler. After installation, check for proper operation of all of the limit and

operating controls, before leaving the site.

• We recommend that secondary (redundant) Low Water Cut-Off controls be installed on all

steam boilers with heat input greater than 400,000 BTU/hour or operating above 15 psi of

steam pressure. At least two controls should be connected in series with the burner control

circuit to provide safety redundancy protection should the boiler experience a low water

condition. Moreover, at each annual outage, the low water cut-offs should be dismantled,

inspected, cleaned, and checked for proper calibration and performance.

•

To prevent serious personal injury from steam blow down, connect a drain pipe to the control

opening to avoid exposure to steam discharge.

• To prevent a fire, do not use this low water cut-off to switch currents over 7.4A, 1/3 Hp at

120 VAC or 3.7A, 1/3 Hp at 240 VAC, unless a starter or relay is used in conjunction with it.

Failure to follow this warning could cause property damage, personal injury or death.

NIN

UTIO

WARNING

1 2 3 4 5 6 ... 11 12

Summary of Contents

Page 1 - Replacement Head Mechanism

INSTRUCTION MANUAL MM-219JReplacement Head Mechanism®Replacement head mechanisms can be installed withoutdisturbing existing equalizing connections or

Page 2 - OPERATION

KTo prevent serious personal injury from steam pipe blowdown, connect a drain pipe to the control opening toavoid exposure to steam discharge.Failure

Page 3 - /16"

11MAINTENANCESCHEDULE:Blow down control as follows when boiler is in operation.• Daily if operating pressure is above 15 psi.• Weekly if operating pre

Page 4 - /4"

Xylem Inc. 8200 N. Austin Avenue Morton Grove, Illinois 60053 Phone: (847) 966-3700 Fax: (847) 965-8379www.xyleminc.com/brands/mcdonnellmillerMcDonnel

Page 5 - INSTALLATION

2Enclosure rating: NEMA 1 General PurposePump Circuit Rating (Amperes)Voltage Full Load Locked Rotor Pilot Duty120 VAC 7.4 44.4345 VA at240 VAC 3.7 22

Page 6

3ApproximateDistance AboveCast Line DifferentialSetting In. (mm) In. (mm)Motorized15/16 (24)Valve Closed5/16 (8)Motorized5/8 (16)Valve OpenBurner

Page 7 - STEP 3 - Electrical Wiring

4PUMP #1OFFPUMP #1ONNORMAL BOILERWATER LINE(19mm)3/4"DIFFERENTIALPUMP #2 ONAT CAST LINE7/8"DIFFERENTIAL(22mm)PUMP #2ONPUMP #2OFFPUMP #1OFFPU

Page 8

• To prevent serious burns, the boiler must be cooled to 80˚F (27˚C) and the pressure must be 0 psi (0 bar) before servicing.• To prevent electrical s

Page 9 - WIRING DIAGRAMS

d. Using a wrench, insert the eight (8) bolts andtighten them to approximately 14-20 ft•lb (19-27 N•m) in an alternating star pattern.GJb. Align the b

Page 10 - STEP 4 - Testing

7IMPORTANT: There must be aminimum space of 1/2" (13mm)between connector fittings andelectrical live metal parts.STEP 3 - Electrical Wiringa. Rec

Page 11 - MAINTENANCE

8Switch OperationFor all Models except 158S and 159SFor Model 158SBoiler feed pump off,burner on, alarm off.Boiler feed pump on,burner on, alarm off.B

Page 12 - Xylem Inc

9WIRING DIAGRAMSFor Motorized Valves, refer to the valve manufacturer's wiring instructions.Pump Control Only1. Install a starter or relay in pum