How important is circulator pump hp rating?


  #1  
Old 10-10-12, 05:51 PM
M
Member
Thread Starter
Join Date: Mar 2005
Location: USA
Posts: 98
Received 0 Votes on 0 Posts
How important is circulator pump hp rating?

I'm swapping out a Taco pump 0010-F3-1IFC rated at 1/8 hp.

The local supply house gave me Taco 0010-MSF1-IFC rated at 1/20 hp.

The supply house pump seems to be the "generic fix it in a pinch" pump which i'm not totally thrilled on.

Is HP rating that important on a pump? should the old pump be rated higher? thoughts? the Taco pump is only 3 years old and it died. at this point i'm going to replace the entire pump and not mess with changing the insert/core/stem/the part that you can swap out in the middle of the pump/motor. is there a better pump out there that i should be shopping for?

Specs to the system:
Forced hot water
Gas condensing boiler - Burnham CHG
3 floor house
single zone
circulator at zone pumping into a check valve (pump goes on valve open and we get heat, pump goes off valve close)
cast iron radiators
piping goes from 1.25" at the boiler and it appears it goes all the way up to 2" in some areas...possible it was steam heat at one point.


thanks for reading...any advice would be greatly appreciated.
 
  #2  
Old 10-10-12, 06:17 PM
PJmax's Avatar
Group Moderator
Join Date: Oct 2012
Location: Northern NJ - USA
Posts: 61,828
Received 1,473 Votes on 1,361 Posts
Big water loop there. I wouldn't opt for a lower rated pump. I'm not a plumber but I do repair work and it seems to me like the Taco pumps just down hold up as well as the Grundfos ones do.
 
  #3  
Old 10-10-12, 06:23 PM
M
Member
Thread Starter
Join Date: Mar 2005
Location: USA
Posts: 98
Received 0 Votes on 0 Posts
definitely...massive water loop. really want to get some zones going on...but the time being i'm just trying to stay warm for the season and worry about it come spring.

it takes a while to drain the entire system too...i can hear the water gurgle for the last 20 min while i'm typing this reply. going to put in some isolation valves so if the pump goes or something crazy i don't have to drain the entire system to service the pump and associated parts.
 
  #4  
Old 10-10-12, 06:36 PM
R
Member
Join Date: Nov 2011
Location: USA
Posts: 423
Received 3 Votes on 3 Posts
When it comes to capability, HP is not really the important issue. You want to focus more on flow and head.

From what I can gather, the "old" pump (Taco 0010-F3-1 IFC) is a single-speed pump with a Flow Range of 0-18.5 GPM and a Head Range of 0-9 Feet.

The new pump (0010-MSF1-IFC) is a 3-speed pump with a Flow Range of 029 GPM and a Head Range of 010.5 Feet.

So at a glance, it appears that the new pump is quite capable of matching the performance of the old pump, depending on speed setting. Comparing actual pump curves would probably bear that out (I haven't looked at the curves).

You need to make sure you remove any air introduced into the system after you change out the pump.
 
  #5  
Old 10-10-12, 06:48 PM
M
Member
Thread Starter
Join Date: Mar 2005
Location: USA
Posts: 98
Received 0 Votes on 0 Posts
specs on new pump (0010-MSF1-IFC)
http://www.pexuniverse.com/docs/pdf/100-51.pdf

specs on old pump (0010-F3-1 IFC)
http://www.pexuniverse.com/docs/pdf/100-20.pdf

so what's the hp rating for?

yeah i go to every radiator 2-3 times to bleed out all the air. takes forever but once it's done...it's done. that's why i want to put in shut of valves so i can isolate the system from the boiler.
 
  #6  
Old 10-10-12, 07:12 PM
D
Member
Join Date: Aug 2009
Location: USA
Posts: 4,946
Received 0 Votes on 0 Posts
so what's the hp rating for?
Everything with a motor comes with a power rating.
 
  #7  
Old 10-10-12, 07:18 PM
M
Member
Thread Starter
Join Date: Mar 2005
Location: USA
Posts: 98
Received 0 Votes on 0 Posts
while we're on the topic of pump head...
since the house is 3 levels does the pump head rating need to cover all 3 levels of the house?
 
  #8  
Old 10-10-12, 07:22 PM
M
Member
Thread Starter
Join Date: Mar 2005
Location: USA
Posts: 98
Received 0 Votes on 0 Posts
so even with a lower hp rating the pump can still pump more than the 1/8 hp rated pump due to...efficiency? pump design?
 
  #9  
Old 10-10-12, 07:56 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 4 Votes on 3 Posts
since the house is 3 levels does the pump head rating need to cover all 3 levels of the house?
In a CLOSED system, height of the system has absolutely NO bearing on pump head.

All you need to do is move water past the pump and 'turn the ferris wheel'.

A closed system is a balanced system, you are both pushing and pulling at the same time. You are not pumping 'up', the system is already full of water.

The only head the pump needs is that which is needed to overcome the friction of the piping system.

This is completely opposite to an OPEN system such as a well pump on a domestic supply system, where the height has as much to do with pump head as the piping friction.
 
  #10  
Old 10-10-12, 07:57 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 4 Votes on 3 Posts
so even with a lower hp rating the pump can still pump more than the 1/8 hp rated pump due to...efficiency? pump design?
Basically speaking, yes......................
 
  #11  
Old 10-10-12, 08:20 PM
M
Member
Thread Starter
Join Date: Mar 2005
Location: USA
Posts: 98
Received 0 Votes on 0 Posts
thank you all for your help. so i'm not going to return this new pump to the supply house.

the only thing i'm not thrilled about is that it seems like it's a "service pump" where it's pretty much an universal pump that an installer would have around since it fits so many applications...but at this point if it's going to work then i'm ok.
 
  #12  
Old 10-10-12, 08:24 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 4 Votes on 3 Posts
Pretty much all of the pumps made these days are physically interchangeable.

I don't think you will have any problem with it at all.

Let us know how it works!
 
  #13  
Old 10-11-12, 05:22 PM
G
Member
Join Date: Oct 2008
Location: USA
Posts: 3,016
Received 13 Votes on 13 Posts
The horsepower rating is at rated flow and head. Mechanical pumping power = flow x head. For the electrical power useage, divide by the combined pump and motor efficiency, maybe 80% or so.
 
  #14  
Old 10-11-12, 07:51 PM
M
Member
Thread Starter
Join Date: Mar 2005
Location: USA
Posts: 98
Received 0 Votes on 0 Posts
new pump is in...still no heat.
radiators are filled with water. open valve and it's squirting water at me.

on this boiler the loop is nice and hot. just not circulating...or maybe not circulating enough?

only other thing that i can think of is the spirovent...can these things clog? the system has been in used for 3 seasons.
 
  #15  
Old 10-11-12, 08:14 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 4 Votes on 3 Posts
Pump definitely has power going to it?

Check valve stuck shut?

Another valve somewhere accidentally shut?

on this boiler the loop is nice and hot
Is this piped as primary/secondary ? you have one pump for the boiler loop to the closely spaced tees on the main pipe, and another pump for the system ?

the spirovent...can these things clog?
I suppose, if you had that much sediment in your system, but I find highly unlikely. It would take a LOT of sediment to clog up that 'brush' that's inside of it.

Just because you get water from the bleeders doesn't mean that you've gotten all the air out of the system. A big old air bubble somewhere in the pipe is as good as a cork at stopping flow.
 
  #16  
Old 10-11-12, 08:22 PM
M
Member
Thread Starter
Join Date: Mar 2005
Location: USA
Posts: 98
Received 0 Votes on 0 Posts
yes the pump is whirling...you can feel and hear it humming. so there's power.

check valve. it's a taco one...there's a screw that you can turn to manually lift it...same issue. if i tap on it you can hear the valve jiggle and it was jiggling when the boiler was filling up.

on the burnham CHG theres a loop that goes in and out of the boiler. there's a pump there but i can feel that hum and the check valve is jiggling..it's like metal tapping sound from the inside. that loop is nice and hot. the hot water is just not passing the zone pump (one zone).

any suggestions on getting that big old air bubble out?
 
  #17  
Old 10-11-12, 08:28 PM
M
Member
Thread Starter
Join Date: Mar 2005
Location: USA
Posts: 98
Received 0 Votes on 0 Posts
to give you an idea the loop i'm referring to...

 
  #18  
Old 10-11-12, 08:59 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 4 Votes on 3 Posts
Have you got what's called a 'purge station' on the main loop?

This would consist of a ball valve with a drain right next to it... if the system is set up for it, you might be able to do a 'power purge'.

Pics of the actual piping would help greatly!
 
  #19  
Old 10-11-12, 09:37 PM
M
Member
Thread Starter
Join Date: Mar 2005
Location: USA
Posts: 98
Received 0 Votes on 0 Posts
red - to zone (cold - no heat)
green - boiler loop (hot)
blue - water in to boiler (if needed)



 
  #20  
Old 10-12-12, 08:37 AM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 4 Votes on 3 Posts
Pics too small... can't see...

In the first pic, on the left side, there is a silver thing, and above it another object that appears to be a gate valve... can you get a closer pic of those?

I would somehow support that expansion tank. When it fails (it will eventually) it will fill with water and that will put tremendous torque load on that tee and other piping.

Is the black pipe entering the rear of the boiler your gas line? There is supposed to be a 'drip leg' on the bottom of that. It should not elbow in, there should be a tee there, and a piece of pipe with a cap on the bottom of the tee.
 
  #21  
Old 10-12-12, 10:40 AM
M
Member
Thread Starter
Join Date: Mar 2005
Location: USA
Posts: 98
Received 0 Votes on 0 Posts
the gate valve i just put in when i drained the system to swap out the pump. that's the return line from the zone.

expansion tank support...do i just use a strap or something around the tank?

according to the plumber and the NYC inspector they said the drip leg is no longer required on the gas line.


here's the pic from the other angle...and bigger pics...sorry about that.
http://i24.photobucket.com/albums/c2.../boiler1-1.jpg

http://i24.photobucket.com/albums/c2.../boiler3-1.jpg

i think the forum shrinks the pics..
 
  #22  
Old 10-12-12, 11:48 AM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 4 Votes on 3 Posts
the gate valve i just put in when i drained the system to swap out the pump. that's the return line from the zone.
Are there no boiler drains anywhere on the main loop?

What we need to do is come up with a plan to purge the system loop. Typically this would be done with a drain and a stop valve right next to each other. You would close the stop valve, connect a hose to the drain, open the feedwater valve and this would force the water to go through the heating zone and push the air ahead of it.

Are there any other valves on the main line that aren't showing in the pics?

(note: haven't looked at the photobucket pics yet...)
 
  #23  
Old 10-12-12, 11:57 AM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 4 Votes on 3 Posts
the gate valve i just put in
You mean that crusty old one with the handle taken off of it? That's new?

Or are you talking about the yellow handled valves? Those aren't gate valves, they are BALL valves.

Gate valves are often a problem because when you close them, the gate wedges into the valve, then when you go to open them again the gate is wedged solid and the stem of the valve breaks out of the gate. When this happens you can't open it ever again... you need to replace at that point. Are you sure that's not the case here?

So that silver (galvanized?) fitting in the first pics is actually a WYE ?

Still don't see an appropriate purge valve setup...

expansion tank support...do i just use a strap or something around the tank?
You maybe could put something under the tank, or a piece of strapping around the elbow that the tank is hanging on and straight up to a floor joist with a screw or nail attaching it.

Anything that will take the torque off the other piping.

according to the plumber and the NYC inspector they said the drip leg is no longer required on the gas line.
Can't imagine why not! In any event, the manufacturer requires it... it's cheap insurance against crud blowing into the gas valve.

Yes... forum does shrink pics. Used to be we couldn't post pics directly, only to a hosting site and then link. In some ways better, but others not so much.
 
  #24  
Old 10-12-12, 12:04 PM
M
Member
Thread Starter
Join Date: Mar 2005
Location: USA
Posts: 98
Received 0 Votes on 0 Posts
oops..yes that's the ball valve that i just put in...not the gate.
the gate valves (i forget about them) they are always on and never been touched. hence the handles are off them. there is a boiler drain inside the boiler cabinet.

yes there's a wye in there at the returns...pretty old enh?

i'll look into straps for the tank..thanks for the tip.

hmmmm...when the plumber was installing it he said it's no longer needed. the gas from the supplier is clean so there's no need for it...(paraphrasing the plumber). i don't know any better so i'm like "ok".
 
  #25  
Old 10-12-12, 12:07 PM
M
Member
Thread Starter
Join Date: Mar 2005
Location: USA
Posts: 98
Received 0 Votes on 0 Posts
there's one drain valve in the boiler. there's the other valve that's next to the loop pump.
 
  #26  
Old 10-12-12, 12:20 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 4 Votes on 3 Posts
I don't think we can use the drain inside the boiler for this... but let me look again ... maybe.

If that don't work, you might need to add a drain next to one of the ball valves on the system loop.

the gas from the supplier is clean so there's no need for it.
Sure the gas is clean! but it's the rust and dust from the inside of crusty old pipes that is the problem ...

there's the other valve that's next to the loop pump.
Another drain? didn't see it... just looked again, don't see another drain.
 
  #27  
Old 10-12-12, 12:27 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 4 Votes on 3 Posts
I think you might need to add another drain valve.

I believe I would put it on the section of pipe in the yellow circle.

Name:  mktbully.jpg
Views: 1725
Size:  36.1 KB

Then, you hook your hose to that and close the ball valve with the yellow arrow.

Open the drain, and lift up on the fast fill bail on the B&G reducing valve.

This will force the water to go through the zone at high speed and push the air out the hose.

Remember water takes a path from high to low pressure and the one of least resistance. The open drain is the low pressure and the fill valve is the high pressure.

If you don't close that valve, the water will not go through the zone, but out the fill valve and the shortest route to the drain.

Closing that valve causes a 'roadblock' and forces the water to take a detour the long way around...

When you do this, watch your pressure. If you let it go above 30 PSI the relief valve will open.

After you purge the air, let go of the bail, close the drain valve, open the ball valve.
 
  #28  
Old 10-12-12, 01:15 PM
M
Member
Thread Starter
Join Date: Mar 2005
Location: USA
Posts: 98
Received 0 Votes on 0 Posts
ok i'll pick up the pieces and put in a valve there. i get what you're saying. the water going up will push the air out and out. basically let the valve open until all the air is out. hope that does it...it's getting cold.
 
  #29  
Old 10-12-12, 01:32 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 4 Votes on 3 Posts
hope that does it...it's getting cold.
I hope so too! cuz if it don't yer gonna be pizzed at me!

But, if the pump is working and you don't have circulation, there must be an air blockage... I hope!
 
  #30  
Old 10-12-12, 06:21 PM
M
Member
Thread Starter
Join Date: Mar 2005
Location: USA
Posts: 98
Received 0 Votes on 0 Posts
NJ thanks for the help...it turns out i was screwed by 3 letters...

IFC

integrated flow check on the pump. i broke down and called the plumber. he didn't know at first but he said let's take off the flow check at the pump and see...well 145 bucks later there's heat. i don't know how it worked in the past but he suspect that it might be the age of parts and things wearing down a little just gave it enough resistance to not lift the iron flow check.
 
  #31  
Old 10-12-12, 07:10 PM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 4 Votes on 3 Posts
I think I know what happened, and it really should have dawned on me...

With the pump mounted in that orientation, pumping UP, you had a pump full of AIR. Those pumps can't pump air, so the flow check in the pump would never have lifted to release the air and start pumping water.

This is actually the SECOND time I've run across this. Should have remembered, sorry!
 
  #32  
Old 10-12-12, 07:25 PM
R
Member
Join Date: Nov 2011
Location: USA
Posts: 423
Received 3 Votes on 3 Posts
Sounds like another example of how many different ways air in the system can lead to head scratching (head banging?) and, unfortunately, check writing.

Good to hear you have heat now.
 
  #33  
Old 10-12-12, 07:34 PM
M
Member
Thread Starter
Join Date: Mar 2005
Location: USA
Posts: 98
Received 0 Votes on 0 Posts
thank you both for your help.

NJ yeah you're right...that's what the plumber said..there was just a pocket of air caught between the check flows and like you said...it was basically a cork.

it wasn't a total loss...i was able to put in isolation valves so hopefully i don't have to drain the entire system down anymore...that really helped tonight since we had to drain down the loop the pump was in. took a few secs to drain and took a few secs to fill back up. usually it takes over 20 min to drain and even longer to fill. so instead of the plumber being here for hours he was in and out in about 30-40 min.

hate to write the check...but i take it as a learning experience.

got a spare taco 0010 pump...maybe i should mess with plumbing the second zone next year...LOL
 
  #34  
Old 10-13-12, 07:41 AM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 4 Votes on 3 Posts
maybe i should mess with plumbing the second zone next year...LOL
You meant ' should NOT ' , didn't you?

Since you have that flow check above the pump, there is no need for the IFC in the pump anyway. But it wasn't the air between the two flow checks that was the problem. Even if you didn't have that second flow check, you would still have had the proplem.

It was the air trapped inside the pump itself, behind the IFC that was the problem.

I don't know why they don't drill little 'air bleed' holes in the IFC, similar to what they have on auto thermostats, to prevent this problem. A tiny hole to let air leak out would not be big enough to cause a problem... I don't think... but the engineers always know best, don't they?
 
  #35  
Old 10-14-12, 08:15 AM
M
Member
Thread Starter
Join Date: Mar 2005
Location: USA
Posts: 98
Received 0 Votes on 0 Posts
ahhh ok...i gotcha.

well the plumber pulled the valve out so it's no longer an issue.

i would like to zone out the house so i don't have 1 t-stat for the entire house.

i know i'm going off topic...but the pipes are set up off two massive loop in the basement. the radiators feed from one pipe and return on the other pipe....looks to be doable.
 
  #36  
Old 10-14-12, 10:32 AM
NJT's Avatar
NJT
NJT is offline
Member
Join Date: Oct 2006
Location: USA
Posts: 23,539
Received 4 Votes on 3 Posts
You thinking electric zone valves? or two pumps?

Given what I can see in your pics, I tend to think two pumps might be the best solution.

If this happens, you would also need another flow check above the pump.

By the way, stepping back to the original problem, the solution I had proposed with adding the drain valve and doing a 'power purge' would have worked to move the air out of the pump. It's always a plus to be able to set up for a purge, so when you knock the system down to set up the zones, add the drain valve.
 
  #37  
Old 10-17-12, 06:46 PM
M
Member
Thread Starter
Join Date: Mar 2005
Location: USA
Posts: 98
Received 0 Votes on 0 Posts
trust me...when the time comes to do this (weather being warmer) i will get the valve plumbed in there so it can power purge.

yes i'm definitely doing the pump and check valve set up. had a bad experience with electric zone valves.

thank you for the assistance and advice.
 
 

Thread Tools
Search this Thread
 
Ask a Question
Question Title:
Description:
Your question will be posted in: