Hi,

We have an old gas fired boiler with radiators throughout the house. I was told that we should add oil to the motor/pump that circulates the water throughout the house, but I'm not sure which or what type of oil to use. I just got back from Home Depot and no one there knew what I should be using. There's a small cap on top of the pump that looks like I'd need something like a WD-40 spray can, but I want to be completely sure I'm using the right type of oil.

Any help would be greatly appreciated!! I'm very new to boiler maintenance so detailed explanations (if necessary) would be great.

Thank you,

Kevin

 

Ackkk not WD40 that would dilute the existing oil and wash out yer bearings.

The cap is at one end (or both) of the electric motor, right?

There should be oil specs on the motor housing or label normally.

I won't try to make an exact recommendation, but many blower motors and larger electric motors that I've dealt with say " electric motor bearing oil or SAE 10 or 20 non-detergent automotive oil".

Normally you can get the oil in with a trigger type flex-spout oil can.

Let one of the Pro's respond before you use anything though, ok? It can wait a few days.

 

The cap is at one end of the motor, although I can take a closer look tonight. Maybe I can find the oil specs somewhere on the motor as well.

I don't think we'll need to turn the furnace on quite yet so it can wait a few days.

I appreciate your help!

Kevin

 

If that's a Blood & Guts Series 100 and you don't need extreme GPMs, I'd just replace it with a Grundfos 15-58. It would pay for itself in electrical savings in a few seasons. 1.75 amps vs 0.7

The 15-58 is way way quieter, maintenance-free and it's an easy change-out.

 

I'm thinking we may have to get a new boiler within the next few years anyway so would it still make sense to get a new pump? Our boiler is probably 30+ years old.

How much does the 15-58 cost?

I know we could definitely use a quieter pump!

Thank you!

Kevin

 

It should cost less than $100... how much less is up to you.

I replaced my pump before my boiler, in a very similar situation... I still use that pump.

 

If you are going to replace the boiler in a couple of years anyway, no way would I replace the pump unless I had to. Unless you have valves on both sides of the circulator (highly unlikely) you are going to loose water. How much depends on pipe size, where the circulator is located, how long it takes you to change it, if flow control valves hold, etc. Then you have to deal with air in the system & getting it out.

Regarding the oil to use: Plain 30w motor oil, preferably non-detergent, is fine. You can also get 20w 3in1 oil in a Blue, Black, & White can which is fine as well. DO NOT use the 3in1 in the Red, Black, & White can. It is way too light. Add about 40-50 drops to the cap closest to the pipe & 5-10 drops in each of the oil ports for the motor.

 

My oil B&G used to get switched on in October and switched off in April or May. Under normal load it 1.75 amps of current. To run my monoflo system properly, the Grundfos 15-58 only needed medium speed (0.70 amps). It was silent, where the B&G sure wasn't.

This difference in amperage works out to about 1.2 cents of wasted electricity per hour of operation at our low rate here of only 10 cents per kilowatthour, many places are 15 cents or even double. I'd run my pump 24 hours a day (continuous circ) and 200 days a year - $58 more a year with the B&G. It cost less the $100 including taxes to buy the new Grundfos and I got to do it myself. It is definitely more of a challenge if there aren't shutoffs near the flanges as Grady points out. My system had gate valves on either side so it only took this first timer maybe 30 minutes and most of that was thinking that I was forgetting to do something. Just make sure the pump, makeup water valve and boiler are switched off to do it and switched back on after. Make sure the pump doesn't turn on with air in that section of pipe.

This is a really good D-I-Y project for some people that have fairly good mechanical aptitude. It can be very beneficial if your pump ever dies on a cold weekend.

 

Thanks to everyone for all your help!!! Does anyone have detailed instructions on replacing the pump just in case?

I was able to check the pump out last night and there are definitely 3 valves for oil. The pump was made by Bell and Gossett corporation, and there are instructions on maintaining the pump although they are very difficult to read. What I can read sounds very similar to Grady's instructions.

I dealt with air in the system last year. The people who lived in the house before us did very little if any maintenance on boiler.

Thanks again for all the help!!!

Kevin

 

All power to the boiler and pumps off.

Make sure the water temp is low enough not to burn you.

Note the direction of flow on the existing pump.

Close the nearest 2 valves on either side of pump.

Carefully disconnect the wiring from the B&G.

Unbolt the bottom pump flange, with a bucket to catch the water in there. Then unbolt the top.

Attach the old pump to a chain on your boat, after draining the oil of course!

Put the new pump in, noting the direction of flow. Yes it does need to be the same.

Reattach the flange bolts. The pump should have new ones and new flange gaskets - use the new ones.

Test the wiring to make sure that the hot and neutral aren't crossed, not likely to affect the pump but do it anyway.

Switch the electrical all back off again.

Then reconnect the wring to the pump.

Then open up the isolation valves and the boiler feed valve and get your pressure back up to 15psi or whatever is appropriate fro the height of your structure.

Then try it out.

You can open the beer once everything is working and not leaking.