RCW University

Browse the RCW archive of answers to questions posed through the years to our experts, as well as magazine, how it works, and training articles. Coming soon: a series of applications videos.

All Questions and Answers

Question: I work for a college that has just had a boiler feed unit installed. The unit is a model # 95CMED-2.0-C35. The unit has a direct steam injection to preheat the feed water. This thing sounds like its going to take off when its calling, really bad water hammer. It is fed from a 15# steam header. Should it have a PRV to reduce the steam# before it goes to the temp. control unit.

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Question: One of our customers has a steam system with two Smith low pressure steam boilers, each rated at 5250 MBH input. They are having a problem with water being carried over into the steam piping when the outdoor temperature drops and steam demand increases. Their chemical treatment regime is excellent and there are no steam pipes coming off the bottom of the headers.

The steam system itself is not physically very large. Almost all of the boiler output goes to a shell/tube heat exchanger right beside the boilers, so there is not much volume in the piping system. I believe that may be part of the problem. The boilers are relatively new, and replaced existing boilers which had more volume in the boilers themselves.
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Question: Can you suggest source for thermostats to control hot water circulation pumps like NRF22 in apartment house applications. I want the pump to turn off when the water in the loop is hot, so as to minimize erosion problems in the pipes. Thermostat should open ~120 oF, close ~110 oF.
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Question: I have a Series 100 Pump that leaks oil. A pump repairman told me to put straight 50 SAW oil. What do you think?
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Question: Does B&G make a variable speed pump suitable for hydronic heating systems that can be controlled with a 4 to 20 ma control signal? If not do you make a pump that can be used with a variable speed drive?
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Question: What are the maximum flow rates for the Flo-Control valves?
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Question: I have a Series 1531, 1-1/4 AC pump designed for 32 gpm @ 42 ft.hd.(6.25" impeller) The differential is 18.5 or 42.7 Ft.Hd. The pump curve gets very flat at that point. Air temperatures at the AHU coil are 77 entering and 67 lvg. Water temps are 45 ent. and 61 lvg. Fan CFM is about 6800. All testing suggests low water flow. Do these pumps tend to drop off in performance when they are so close to this operating point?? My flow device is not reading properly. I believe my control valve CV Value is too low. (3/4 FP Ball at 10CV). I am going to install a valve with CV of 15 or more., depending on availability. Please advise how to read these curves accurately at similiar operating points?
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Question: We recently had a "gould" Pump installed on a well in Lake Winola Pennsylvania. The company name is ITT. Is this the right place to ask for assistance with a Gould Pump from ITT?
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Question: I hope you can help me out with this one! One of the pumps on my hot water boiler is on the fritz. Our oil dealer said the repair is going to cost me around $500.00. Well I told him thanks but I think I can repair it my self for a lot less. My problem is that the serial number plate has been mysteriously removed. The only ID I can find on the pump is a tag that says "100 - P7-4 ". From looking at your web site i can determine that I have a series 100 pump, but what model is it?
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Question: I hope you can help. Every plumber that looks at my house gives me a different story. I have an 1800 sq foot house that is 75 years old and fairly well insulated. There are 10 cast iron radiators and 2 cast iron base boards. The system is an old gravity system that has been converted to a single zone pump system. The house gets enough heat but it is not evenly distributed. I would like to split the house into two zones 1st & 2nd floors. I think running 2 loops of copper around the basement and installing monoflo T's and balancing valves may be the way to go. Questions; Is this a good way to go? What size should the loops be 3/4" or 1" or larger? Currently 1 1/4" supply is being fed into older larger pipes. Do I need monoflo T's and balancing valves. If I install balancing valves on the mains between the supply and return of each radiator. Why would I need Monoflo T's. (I want balancing valves for better control) If I need monoflo T's. Does it go on the supply or return or both?
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Question: I have a customer using a continuously running pump with chlorinated pool water being sent into a heat exchanger. The manucturer specs call for 3 gpm and the coil has a pressure drop of 6psi. The piping is about thirty feet of inch and quarter PVC and 12 90 degree elbows. What pump would you recommend for this situation?
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Question: If a steam boiler has 2 mains pipped separately from the top of the boiler,do you need 2 Hartford loops ?
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Question: I have a residential boiler system, with a B&G circulator. The motor kept experiencing thermal cutoff, but could sometimes be coaxed into running by tapping with a hammer. The motor is #M09180. Disassembly reveals that the copper switch contact (looks a little like a wishbone) is completely worn out. The web site does not show a M09180 motor, but does list a M09181 that has the same specs as my motor. For M09181, a part is listed as a "switch plate" #BG_118253.
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Question: I have a customer with an 4" steam Valve, ITT General Hydromotor SN 7839A, 115VAC. Who can I contact for parts or new valve?
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Question: Do you know if it is still possible to get replacement parts for a B&G Oil-less Vacuum Pump Model No. SYC18-1 ID NO. CPE00A-0201K HF or any literature?,
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