Low Water Cut-Off – ITT McDonnell & Miller – Series 150S & 157S

We have very recently discovered that manual reset only versions of the McDonnell & Miller Low Water Cut-Off 150S and 157S, the versions with snap switches, may not operate correctly throughout their operating temperature range. In order to avoid the chance of any field failures, which could lead to fire, we will replace or provide means to repair these products. This kit is meant to facilitate the repair of certain variations of these products.

Federal law requires that you must promptly take all action necessary to insure repair or replacement of the control.

Again, this applies only to the manual reset versions. The standard versions of the 150S and 157S are unaffected, and can be sold and used with confidence. All products with a date code of September 1998 (98J) or later, are also unaffected, and can be used with confidence.

The products to be inspected and repaired are listed below:

172104 150S-B-M
172702 150S-M
172802 150S-M-MD
172901 150S-M-J
173203 150S-M-HD
173302 150S-M-MD-HD
173802 157S-A-M
175402 157S-M
175412 157S-M-MD
176551 157S-RB-M
177006 157S-RL-M
177306 157S-R-M
178502 158S-M
178702 158S-M-HD
310463 SWA-150S-M

Date codes of products to be inspected and repaired be are listed below:

96J September 1996
96K October 1996
96L November 1996
96M December 1996
97A January 1997
97B February 1997
97C March 1997
97D April 1997
97E May 1997
97F June 1997
97G July 1997
97H August 1997
97J September 1997
97K October 1997
97L November 1997
97M December 1997
98A January 1998
98B February 1998
98C March 1998
98D April 1998
98E May 1998
98F June 1998
98G July 1998
98H August 1998


Field repairs will work as follows:

A) S Series manual reset units built between September of 1996 and August of 1997
• These units cannot be repaired in the field.
• These units can be easily identified by the white reset button on the side of the switch housing.
• Install a current head unit, either a 150S-M-HD or 150S-M-MD-HD, as appropriate.
• We will replace those units at no charge. Contact your local wholesaler for details.
• Also, you should be prepared to return the old heads. Again, contact your local wholesaler for details.
B) S Series manual reset units built between September of 1997 and August of 1998
• These units can be easily identified by the large red reset button on the bottom of the switch housing.
• These units should be field repaired using the enclosed kit.
• Additional field repair kits and instructions are available for immediate shipment, at no charge, from your local wholesaler, from our location here in Chicago, or from our local representative in your area.
• It is important that you help us keep track of where each repair kit is used. The enclosed reply card should be returned to us once a repair is complete.

C) Reasonable actual costs for field labor associated with either head replacement or field repair will be reimbursed. In order to be reimbursed, we must have received the reply card
or the replaced head. For details, please call Steve Mueller, our Customer Service Manager, at 773 267-1600.

We realize that this action may be seen as an extreme inconvenience, particularly as we enter the heating season. However, we believe it prudent to promptly act to insure that product in the field can be relied upon to perform safely. We apologize for any inconvenience this will cause.

John Cecilia
Marketing Manager
ITT McDonnell & Miller


November 5th, 1998