circulator pump sizing (old vs new) - boiler strugglings to heat house
#1
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circulator pump sizing (old vs new) - boiler strugglings to heat house
Hi everyone,
My old circulator pump (TACO 1/8 HP, 1725 RPM, FR 48, MOD 5KH32EG129EX) was leaking and the service person replaced it with a TACO 007-f5. The 2 levels on my house that I’m trying to heat is about 1300 sq feet. I can attach pics if someone tells me how to attach.
Now, my house is struggling to get heated. The hot water from the boiler is getting divided into both the sides of the house (same one zone). The right side is getting warmed up with no problem, but the left side is barely getting warm. The service person tried to bleed the water and said that there may be air pockets and when he left he said everything is fine. But, now, 2 days later, my boiler is struggling to warm the house. I very faintly feel the heat when I have my hand near the baseboard. This is happening on only one side of the house.
I’m thinking whether the new circulator has the same capacity of the older one? I’m no expert here, any help on sizing this would be very helpful. The new one says its 0-25 gmp and I’m unable to find the same for the older one (pic attached). Can anyone tell me what the older one’s capacity is? Whether the service man replaced the right capacity pump?
Any help would be highly appreciated. Can someone tell me how can I attach images?
Old 1
Old 2
Old 3
New1
New 2
My old circulator pump (TACO 1/8 HP, 1725 RPM, FR 48, MOD 5KH32EG129EX) was leaking and the service person replaced it with a TACO 007-f5. The 2 levels on my house that I’m trying to heat is about 1300 sq feet. I can attach pics if someone tells me how to attach.
Now, my house is struggling to get heated. The hot water from the boiler is getting divided into both the sides of the house (same one zone). The right side is getting warmed up with no problem, but the left side is barely getting warm. The service person tried to bleed the water and said that there may be air pockets and when he left he said everything is fine. But, now, 2 days later, my boiler is struggling to warm the house. I very faintly feel the heat when I have my hand near the baseboard. This is happening on only one side of the house.
I’m thinking whether the new circulator has the same capacity of the older one? I’m no expert here, any help on sizing this would be very helpful. The new one says its 0-25 gmp and I’m unable to find the same for the older one (pic attached). Can anyone tell me what the older one’s capacity is? Whether the service man replaced the right capacity pump?
Any help would be highly appreciated. Can someone tell me how can I attach images?
Old 1
Old 2
Old 3
New1
New 2
Last edited by NJT; 10-30-10 at 09:57 AM. Reason: removed errant 'example' link
#2
Hi Saturn, set up a free account at a photo hosting website. I like Image hosting, free photo sharing & video sharing at Photobucket . Upload the pics there and come back here and drop a link to the album so we can view.
The 007 is more than likely up to the job, and there probably IS air in the loop. Since fresh water has tons of dissolved oxygen, when it's heated a few times that O2 comes out and reforms the bubbles... that's why it worked a few days... I'm sure the guy had to drain the system to replace the pump, yes? So you've got all new water... after a while, the air should all go out and you should be OK...
Let's see the pics and go from there.
The 007 is more than likely up to the job, and there probably IS air in the loop. Since fresh water has tons of dissolved oxygen, when it's heated a few times that O2 comes out and reforms the bubbles... that's why it worked a few days... I'm sure the guy had to drain the system to replace the pump, yes? So you've got all new water... after a while, the air should all go out and you should be OK...
Let's see the pics and go from there.
#4
First things first... you need to get him back to fix that wire where it enters the new circ... that is awful... how could he leave it like that? The metal sheath on the cable is split, and the wires are exposed... that's just plain WRONG! (not to mention dangerous, if the wire gets nicked by the sharp edge) ... There should also be a 'redhead' insulator stuck in the end of the metal sheath to protect the wires... should look like this:

photo courtesy popularmechanics.com
It's stretched too tight... He should have replaced the cable with a longer piece... or simply turn the pump 180° so the cable was long enough...
Bottom line is that needs to be fixed... soon!
While he's there doing what he should have done right the first time, ask him to bleed the air again, and watch what he does... you shouldn't have to pay for him to come back and fix that wiring!
OK, take some more pics... show us all the piping around the boiler and if you have the right valves and such, we can walk you through what you need to do to get the air out... in addition to the close shots, you need to take some from further back so we can see how it all fits together... if you have the right valves, it might be a simple matter...

photo courtesy popularmechanics.com
It's stretched too tight... He should have replaced the cable with a longer piece... or simply turn the pump 180° so the cable was long enough...
Bottom line is that needs to be fixed... soon!
While he's there doing what he should have done right the first time, ask him to bleed the air again, and watch what he does... you shouldn't have to pay for him to come back and fix that wiring!
OK, take some more pics... show us all the piping around the boiler and if you have the right valves and such, we can walk you through what you need to do to get the air out... in addition to the close shots, you need to take some from further back so we can see how it all fits together... if you have the right valves, it might be a simple matter...
#5
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So far, the takeaway point for me is to get the service person to fix the wiring.
Now, I'm including the pics of my whole boiler setup. Also, I've included links of both my old and new circulation pump specs. Please see whether this is sized correctly and the new one can handle the old pumps capacity
Old Pump Spec
New Pump Spec
Boiler
Domestic Water
Zones (problem in Zone 1)
Zone 1 returns (prob in return 2)
Valves for bleeding
As you can see in the pictures, I have 2 zones. I don't have any problem with Zone 2.
I have 2 loops in Zone 1. Loop 1 is fine, but loop 2 is where the problem exists. You can see in the picture where the loop 1 and 2 joins and then it goes to the new pump.
The baseboards in loop 2 barely gets warm. I could only feel the heat very faintly. I was thinking of the very nature of how loop 1 & loop 2 joins, the circulator pump is pulling return water from loop 1. Any theories?
Bleeding: I have 2 valves in Zone 1. The one in the top has a drain and this is what the service person used to drain. The second value (bottom one) doesn't work (so, I was told). He was increasing the pressure to 20 psi before draining them. I don't know how, if the second valve worked, would have helped bleed the system easier/better, but that's what he told me. Any advice on how I could do this myself would be very helpful.
Thank you and waiting for your guidance.
Now, I'm including the pics of my whole boiler setup. Also, I've included links of both my old and new circulation pump specs. Please see whether this is sized correctly and the new one can handle the old pumps capacity
Old Pump Spec
New Pump Spec
Boiler
Domestic Water
Zones (problem in Zone 1)
Zone 1 returns (prob in return 2)
Valves for bleeding
As you can see in the pictures, I have 2 zones. I don't have any problem with Zone 2.
I have 2 loops in Zone 1. Loop 1 is fine, but loop 2 is where the problem exists. You can see in the picture where the loop 1 and 2 joins and then it goes to the new pump.
The baseboards in loop 2 barely gets warm. I could only feel the heat very faintly. I was thinking of the very nature of how loop 1 & loop 2 joins, the circulator pump is pulling return water from loop 1. Any theories?
Bleeding: I have 2 valves in Zone 1. The one in the top has a drain and this is what the service person used to drain. The second value (bottom one) doesn't work (so, I was told). He was increasing the pressure to 20 psi before draining them. I don't know how, if the second valve worked, would have helped bleed the system easier/better, but that's what he told me. Any advice on how I could do this myself would be very helpful.
Thank you and waiting for your guidance.
#6
If that valve is no good, I would replace it with a ball valve. The idea is that you shut that valve and open the hose bib. When you fill the zone with water, you are able to force the air through the zone and out of that hose bib. Because that valve is closed, the air will only go in one direction.
Where is your expansion tank? Is it a steel tank up at the ceiling?
Where is your expansion tank? Is it a steel tank up at the ceiling?
#7
Yes... let's see where your expansion tank is...
I also want to see the rest of the line that feeds the boiler water from your domestic... In the pics, there is a red handle valve to the left of the boiler along the green block wall... is that the line from your domestic plumbing that feeds water to the boiler?
I would also like to see where the supply (hot) side splits to go to each of the two loops in the problem zone... you are only showing the return side.
If that valve is not working, there's no way to 'purge' the air from that zone. The idea behind the drain above the 'stop' valve is to (as drooper pointed out) is to be able to force the water through the loop at a flow rate fast enough to push the air ahead of the water. Normal flow rate when heating is not fast enough (usually) to move these air bubbles. By closing that valve, you are creating a 'detour' for the incoming water to the system. If you don't close that valve, the incoming water will simply flow through the boiler and out the drain. It will take the path of least resistance and you will never force the water through the loop.
So, let's see the rest of the stuff we need to see and go from there... take pics of everything related to the boiler... we need to see it all.
I also want to see the rest of the line that feeds the boiler water from your domestic... In the pics, there is a red handle valve to the left of the boiler along the green block wall... is that the line from your domestic plumbing that feeds water to the boiler?
I would also like to see where the supply (hot) side splits to go to each of the two loops in the problem zone... you are only showing the return side.
If that valve is not working, there's no way to 'purge' the air from that zone. The idea behind the drain above the 'stop' valve is to (as drooper pointed out) is to be able to force the water through the loop at a flow rate fast enough to push the air ahead of the water. Normal flow rate when heating is not fast enough (usually) to move these air bubbles. By closing that valve, you are creating a 'detour' for the incoming water to the system. If you don't close that valve, the incoming water will simply flow through the boiler and out the drain. It will take the path of least resistance and you will never force the water through the loop.
So, let's see the rest of the stuff we need to see and go from there... take pics of everything related to the boiler... we need to see it all.