Pump Failure- Replacement or retrofit or repipe time?

iced98lx

Our 1978 utica boiler is still going strong but this last spring the 1/12 B&G 100 series pump died on me, completely locked up.

As a typical homeowner does, I've waited until the fall to replace it. We do have minisplits that provide heat in the mean time, so we're not without all heat.

The question now becomes, direct replacement? Something better? Opportunity for a repipe?

We've got 5 zones, here is the current setup:

I added in the Taco zone controllers and fuel smart hydrostat and the air scoop- all of which have been working great. My thought process is flipping the 100 series for something that can do constant pressure as I could audibly hear the pump straining when just a small zone was open (we have two 500 sq ft bedroom/bathrooms on their own zones).

We're not pumping away obviously, I've thought about just getting the cutter out and going to town, but…. "It worked".

It's all baseboard slantfin which my wife hates the look of. I wanted to just heat the floors (we have access to the underside) but with all that I'm hearing from flooring guys these days about wood floors after a few years of heated floors I'm leaning away. She wants to retrofit some new cast iron radiators (would fit with the theme of the house).

Opinions and input is welcome.

And yes, before someone says something the summer clutter around the boilier will be cleaned up when I do the yearly boiler cleaning, it won't be ran that way ;)

Ironman

We really need to know how many btus the house needs to make a precise recommendation, but a Grundfos Alpha should do.

iced98lx

That is entirely fair @Ironman I've calculated whole house load at 80k btu's as the house sits now, by zone:

Main Floor: 30k
Family Room: 22k
Master: 10k
Bedroom 2: 7k
Bedroom 3: 7.5k

HomerJSmith

Ya, you certainly have your share of issues. The question is, is the heat output satisfactory, if so, what is your object and is it worth the trouble. If you can do the work, then, bring out the cutter. I would. But, to satisfy your Missus, you're talking about a major change. That's summer work not something you want to do in the winter.

You can think about what you are going to do and even if you wait until next summer to make the changes, you can start accumulating the parts that you are going to need, now, before the prices go up.

The B&G 100 has a flat curve which the Alpha doesn't and is great for ZVs. However, you might need the head that the Alpha provides. The 100 is kinda antiquated and an energy hog. You're the best judge of what to do if the 100 is failing. I would replace it with an Alpha.

EBEBRATT-Ed

You need to find out if the 100 motor is bad or the bearing assembly. Bearing assemblies need oil (the motor does as well). You might get it to free up until you decide what to do.

You could replace either the bearing assembly or the motor which (with B&G high prices) probably cost as much as a complete new circ.

hot_rod

Any of the ECM pumps that have delta P function would ba a good choice. The 15-58 Alpha has a zone valve setting. So it modulates flow based on zone valves opening and closing

You will pick up some efficiency on the electrical side and the system will not over pump when 1 or 2 zones are calling.

iced98lx

https://forum.heatinghelp.com/discussion/comment/1905896#Comment_1905896

Yeap, I think we're past the point of a complete boiler room re-pipe for the year. I keep putting off considering a boiler replacement but this one is more than twice the output I need- should probably just put a fancoil in the garage off it to lengthen the cycle times a little bit.

Heat is fine except in the main floor where we just don't have enough radiators when the temp is below zero. We have a plan for that.

https://forum.heatinghelp.com/discussion/comment/1905899#Comment_1905899

It's the bearing, I pulled the motor and it spins, the bearings are bad. Frustrating since I was hyper vigilant on the oiling of both, but that is what happens.

https://forum.heatinghelp.com/discussion/comment/1905906#Comment_1905906

Thanks, I think I am going to just put a 15-58 alpha in. For the cost vs parts for the B&G seems like an ok move for now, I appreciate the input!!

HVACNUT

The flue is drastically reduced. It looks like a big 1" gas valve thats been bushed down to 3/4". What's the BTU rating on that boiler? There's no counterbalance on the draft regulator so the damper is in the wrong position. All on a boiler that has its own draft regulator and source for diluting flue gasses. I've never seen that except on a power vent. But even that wouldn't be correct. Then there's that extrol. That's some support.

New Hydrostat. New circulator. New cast iron radiators that would go with the theme, but the same 1978 obsolete micro zoned boiler with no rollout or spill switches. Possibly an incorrect retrofit gas valve, and definitely incorrect flue piping. And that electric panel cover has been sitting there for months. 👍

Steamhead

https://forum.heatinghelp.com/discussion/comment/1905972#Comment_1905972

I noticed the smoke pipe too- does it go to a power venter?

Kaos

@iced98lx Often cold main floors are cased by leaky basements. Fixing the air leaks there will bring the basement temperature up and make the main floor much warmer. Mine went from around 50f to over 60f by replacing the leaky single pane windows and air sealing the rim joist area. The comfort on the main floor improved significatly and fuel use went down. Pretty good win for a bit of elbow grease.

https://www.insofast.com/resources/interiors-resources/garages-floors-ceilings/air-sealing-the-rim-joist

HVACNUT

https://forum.heatinghelp.com/discussion/comment/1905982#Comment_1905982

It probably does, but I don't see a spill switch. Its hard to see the wiring but I only see XX from the zone panels to TT in the Hydrostat, and B1,B2 looks like its going directly to the gas valve. What would prove the power vent?

iced98lx

Thanks for the extra notes, It is powervented. It has the correct gas valve (it was converted from LPG to NG) - the guys that did it ran a full combustion analysis on it when it was done to make sure it was burning right. It has a rollout switch, which was added when the power venter went on.
Sequence appears right, power venter for some amount of time, then burner, burner off, power venter runs x seconds after. But I'm not HVAC tech, just a parts swapper at best.

@Kaos appreciate the note, the basement has all the rim joists fully insulated but there is no actual heat besides the boiler, so it's feasible a little heat in the basement would help the great room stay at temp, not like the boiler can't provide enough output with a zone added on.

Kaos

It really depends on what the rim joist is insulated with. If it is rigid insulation sealed in place with canned foam, then you are good. If it is batts stuffed into the joist ends, the only thing those are doing is filtering the air leaks, those should be take out and replaced with either rigid insulation of spray foam.

hot_rod

spray foam the gaps around the rim, then the batts work okay. It is a bit less $$ then all foam r-value.