Manual

ManualsBrandsXylem ManualsPumpsIM 16 Seal-less Centrifugal Canned Motor Pumps For Instant Hot Water Recirculating System (obsolete)

Installation & Operating Manual

Please read this manual carefully before attempting to install, operate or maintain the product described. Failure to

comply with the information provided in this manual could result in personal injury and/or property damage. Retain

this manual for future reference.

Laing Thermotech

Instruction Manual

INSTALLER: PLEASE LEAVE THIS MANUAL FOR THE OWNER’S USE.

Seal-less Centrifugal Canned Motor Pumps

For Instant Hot Water Recirculating System

SM-303/353-B

SMT-303/353-B

SM-909/959-B14

SMT-909/959-B14

UC-303/353-B

UCT-303/353-B

UC-909-BW-14

UCT-909-BW-14

with 24 hour timer

with 24 hour timerwith 24 hour timer

About Recirculation Systems

Air in the System: A properly installed system should include a method of automatically venting the

air that enters the water supply line during use. Air enters the system each time fresh, cold water is

introduced into the hot water heater. Air may also enter the system any time a plumbing line is

opened, for instance during a faucet/taps change or adding a sprinkler system.

Water Pressure: A recirculating system is a pressurized system operating at the city water pressure, as

determined by the pressure regulator on your line, or by a well pump, if you are on a well system. In

most residential plumbing systems, water pressure is set at 35 psi (241 kpa) and above. Below 35 psi (241

kpa), water pressure may not be sufficient to fill the pipe diameter, leaving space for air to accumulate

in the lines. If your system pressure is less than 35 psi (241 kpa), use the next larger pump on the Pump

Selection Guide.

Multiple Floors: Because the system is pressurized, the number of floors in a home is not taken into

consideration in sizing the circulating pump. The pump has only to produce continuous flow at a

pressure sufficient to overcome the friction losses created by the piping in the house water supply line

and the return line.

SM(T)-303/353-B

SM(T)-909/959-B14(18,21,26)

SM(T)-1212/1212B-18(21,26)

UC(T)-303/353-B

UC(T)-909/959-B-14(18,21,26)

Summary of content (8 pages)

PAGE 1
Installation & Operating Manual Please read this manual carefully before attempting to install, operate or maintain the product described. Failure to comply with the information provided in this manual could result in personal injury and/or property damage. Retain this manual for future reference.
PAGE 2
Oversized Pumps: Pumps should not be so large as to produce flow rates that may eventually erode holes in the pipes. According to the Copper Development Association, excessive erosion occurs at a velocity of about 5 ft. (1.5m) per second and higher; or about 4 GPM (15 LPM) in 1/2” (5/8”) Type M copper pipe; and 8 GPM (30 LPM) in 3/4” pipe. Use the recommended recirculation line size shown in the Pump Selection Guide. Laing pumps are sized so that flow velocities are well below these limits.
PAGE 3
UC/UCT Models A. Return into Cold Water Line at Top of Water Heater fig. 1 B. Return to Drain Valve at Bottom of Water Heater fig. 2 SM/SMT Models A. Return into Cold Water Line at Top of Water Heater fig. 3 B. Return to Drain Valve at Bottom of Water Heater fig. 4 Note: The Air Vent and Hose Bib are not required with UC/UCT-01 models. These models have a built-in air purge valve. Above diagrams are for single line returns only.
PAGE 4
UltraCirc Models The UC and UCT-303/353 models incorporate a shut off valve and check valve into the brass pump housing eliminating the need to install these components. Models with a 01 designation have a built-in air bleeder valve. These models are supplied with 1/2” (5/8”) union fittings. These fittings should be removed from the pump housing before soldering to avoid damaging the internal valves. For SM(T) - 909/959 Models This unit may be installed into the pipe system without disassembling the pump.
PAGE 5
Wiring Diagrams for Units Not Supplied with a Cord. SM-303 SMT-303 red yellow black red yellow brown white red black green red brown brown red black black white green 13. If you have an SMT or UCT timer pump, set your timer in accordance with the instructions below. Timer Controlled Operation If timer controlled operation is desired, the timer may be programmed to allow the system to operate during the hours desired (i.e. “ON” from 7:00 a.m. to 9:00 p.m. and “OFF” from 9:00 p.m. to 7:00 a.m.
PAGE 6
Notes: Keep The Hot Water Temperature Below 140ºF (60ºC): Higher temperatures can cause calcium and magnesium elements to come out of solution and create solids which could not only cause damage to the pump but also reduce water heater efficiency and premature failure of the water heater. Hard Water Conditions: Use a water conditioner. Hard water can cause scale build-up and eventually reduce the life of the pump and other system components.
PAGE 7
Trouble Shooting Noise in the System: The pump should be virtually noiseless during operation. The rotor may make a brief but hardly perceptible fluttering noise immediately after the pump is turned off. During normal operation, an occasional air bubble may pass through the pump housing causing a momentary gurgling noise. However, if noise at the pump persists for any prolonged period, correct the problem (see below).
PAGE 8
Thermal Safety WARNING: - Extreme Temperature Hazard - If the pump, motor or piping are operating at extremely high or low temperature, guarding or insulation is required. Failure to follow these instructions could result in serious personal injury, death and/or property damage. Electrical Safety WARNING: - Electrical Shock Hazard - Electrical connections are to be made by a qualified electrician in accordance with all applicable codes, ordinances and good practices.