Bell & Gossett Series 100 Question

jonas

I have a radiant heat (hot water) system in my home and the bell and gossett series 100 motor is noisy. It makes a low growling-type noise when it is running. I thought of replacing the motor but someone told me that I should just be able to replace a part inside of it instead of the entire motor. I would appreciate any insight that someone could provide.

Unknown

Check the rubber motor mounts

on each end of the motor.

When they start to sag (from over oiling the motor), the coupling that connects the motor to the pump becomes out of alignment.

Changing just the noisey coupling won't cure it. It will eat up the new coupling, too.

Change the motor mounts with the coupling, if they aren't new and crisp looking. If the pump bearing isn't free and smooth turning, that would need to be replaced, too.

Noel

J.C.A._3

YEA

What Noel said! I wish I had a buck for all the sets I've done over the years and he is speaking the truth. Change them all together and your problems will be gone.

One other thing, check to see if there is anymore "wicking" (cotton) material in the bearing housing. I've also seen this disappear more than once. If there isn't anything to hold the oil there, it will have a large stain under the pump. Chris

Chuckles_2

toss it

Modern motors don't need oiling; the 100 is a pain. The b&g NRF-33 and Taco 0010 have the same curve as the b&g 100 and cost around $100.

Weezbo

I agree.

lose it entirely Your well rid of it.

tim smith

B& G 100 circulators

I have to say that those circulators, which many I work on are older than most of us here on the wall. When the last cartridge pumps is gone, the series 100s will still be there cooking. I do use cartridge units on most jobs, but the B&Gs have worked for 50 + years on many jobs we take care of. New couplers and motor mounts periodically and every decade or so a new bearing assembly. So choose for yourself. But, that pump if kept oiled and couplers and motor mounts will probably give you many more years of great service. Good luck,Tim. my 2 Cents worth

Ken D.

B&G

Truer words were never written. As part of our service contract, the motor mounts, oil wicks and couplers are inspected and serviced if needed. We also don't go overboard with oiling. over oiling is one of the biggest problems with them. We have many, many B&G circs. of several types that have not had a breakdown in decades. Maintenance is the key.

Boilerpro_3

They have completely different curves!

The 100 is designed for high flow (nearly 35 gpm) and low head....Max 8 ft. The Nrf-22 maxes out at 22 gpm and 15 ft head....making it a very poor choice for zone valve applications with low flow need zones.

Better check your data, guys!

Boilerpro

Boilerpro_3

Sorry, misread

> The 100 is designed for high flow (nearly 35 gpm)

> and low head....Max 8 ft. The Nrf-22 maxes out

> at 22 gpm and 15 ft head....making it a very poor

> choice for zone valve applications with low flow

> need zones.

>

> Better check your data,

> guys!

>

> Boilerpro

Boilerpro_3

Sorry, misread

But have never seen them for less than $100.00.

Boilerpro

[Deleted User]

Pump

You may want to contact a contractor that is familiar with radiant heat. As was all ready mentioned, the B&G 100 is not a high head pump. Radiant applications typically require a high head pump, you may not need all of that flow either. If you go with a wet rotor pump (Grundfos Brute, B&G NRF22 or Taco 008) you will save on maintenance and probably have a pump that better fits your system.

Ken D.

B&G

I guess it depends on the age or type of radiant system. Out of the over 17,000 radiant homes in Levittown,Pa., 95% of them had Series 100 pumps. The remaining original B&G systems are still working after+ 50 years.

John White

I'm curious as to why one would want to keep maintaining a product to make it work if there are products available that need NO maintenance(ever) and will run as such far longer than the one needing maintenance.
Just curious.

Boilerpro_3

Depends

I've seen well maintained B&G three piece circs that are over 50 year old with NO new parts. Oil is still a better lube than typically dirty system water. However, with the lack of maintenance prevalent on most systems, I go maintenance free typically myself.
Also, very few Maintenance free pumps have the very desirable flow characteristic of broad, flat pump curves which allow head developed to remain flat over a large variation in flow. The B&G SERies 60 pumps are about the only ones. The NRF-33 is better than most, not so sure
about the 110.

Boilerpro

Chuckles_2

why series 100

The only series 100 I've seen (in the home we bought last year) was rattling and on its last legs after 30 years of neglect, but it still felt more solid than the Grundfos 15-58 that I replaced it with. It was certainly much heavier. I suspect modern pumps will not last as long; they are disposable, like everything these days.

Incidentally, the Grundfos 15-58 has multiple speeds, and even its highest speed is somewhat lower than the series 100. I found that all our radiators worked fine even on medium speed! The series 100 is a workhorse that moves an awful lot of water in a low-head (former gravity) system: over 20 gpm, which at deltaT=20 will deliver over 200,000BTU. Everyone used series 100s in the old days, but that doesn't mean everyone needs it. We certainly didn't.