Outdoor Wood Furnace Info
All-Purpose OWF Discussions => Plumbing => Topic started by: kommandokenny on March 16, 2015, 07:28:16 AM
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Pump failure looks to be a concern with my setup, and others.
I have a backup automatic generator and backup propane heat.
If the boiler pump fails and I’m not around,, the whole operation is in jeopardy.
I can get another cartridge for the pump.
Don’t like the idea of changing it outside at the boiler at -40.
We know it will be close to -40 when it fails.
If I’m home when the pump fails, I would have a very short window to change it out, before the lines at the back of the boiler freeze.
If I’m not home …….forget about it.
I’m installing valves inside the basement to drain the lines before I would attempt to replace the pump cartridge.
I’m kind of a belt and suspenders kinda guy and was thinking about adding another pump, in series, inside the house.
Would this be feasible?
Could I leave it turned off till needed
Would water flow through it easily?
Could I use a smaller, cheaper pump, as backup?/
Is there anyway to hook it up to come on automatically, if the main pump at the back of the boiler fails?
kk
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I'm not convinced you'd freeze up at the back of your boiler if the pump failed. Seems like that would be the last place to freeze up since the fire would still be going, heating the water, and at most the back of the stove would be the only "dump zone" while the pump is seized.
That said, it's an interesting idea. I wonder if you could be them in line on a trip breaker of some kind so that if the one fails the other immediately comes on. They'd have to both be outside though.
You mentioned draining the lines in order to replace the pump. I had my installer put an isolation valve on each side of the pump so if it does fail, I can just turn off the valves, replace the pump, open the valves back up, back in business. You may want to do that as well.
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I'll post a pic of the back of the boiler,,,,,,,,,, then factor in -40 c or f.
It's insulated but will freeze quick.
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Just my opinion but i think alot of us guys are way over thinking our owbs, its a simple system , why do we always over complicate things, i can see adding a few little things to make them run easier, but really we are always over doing it...just my opinion, and remember the more things we add ,the more things that can go wrong when its -40 out...
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You mentioned draining the lines in order to replace the pump. I had my installer put an isolation valve on each side of the pump so if it does fail, I can just turn off the valves, replace the pump, open the valves back up, back in business. You may want to do that as well.
I would hopefully just replace the cartridge and leave the pump bolted up .
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Just my opinion but i think alot of us guys are way over thinking our owbs, its a simple system , why do we always over complicate things, i can see adding a few little things to make them run easier, but really we are always over doing it...just my opinion, and remember the more things we add ,the more things that can go wrong when its -40 out...
:post:
KISS = Keep It Simple Stupid
Just a little something that should be beat into every engineer before they receive their degree.
15 years ago when I got my home built up and running I installed a Grundfos 26-99, its still in use now.
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-40 will freeze this up quick.
(http://i40.photobucket.com/albums/e212/kommandokenny/P3160002.jpg)
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So far, my idea seems to be overkill :bag:
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I agree -> KISS, is the way to go
As long as you have a back up pump available, i.e. on the shelf you should be fine. BTW, why travel when its -40 c/f that is too cold to be outside
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I added a second pump this winter for two reasons. To see if it would increase flow and for a backup. I have an Alpha 15-55 just before my hx which was showing on it's readout 6 gpm and 43 hz. I added another 15-55 on the other side of the hx pumping back to the boiler. Both pumps showed 43 hz and 8 gpm with the occasional bump up to 9, I'm thinking because it is close and maybe water temp makes a difference.
After Kenny posted I decided to see what one pump would do, so I unplugged the second pump and left it alone for an hour.. The hx stayed at 43 and the flow dropped back to 6 gpm, so the second pump isn't causing much of a restriction.
It worked for me, and if it hadn't I would've taken the second pump out and and saved it for a backup. A few years ago just for a hoot I bolted a 007 to the inlet of the 15-55, and I believe I gained a gallon or so of flow. I've got some pics somewhere I'll look up.
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So far, my idea seems to be overkill :bag:
Well, simplest way I see of doing this is to get another pump the same size as the one you have now, install a tee before and after the pump, plumb both pumps in so they are side by side, both pumps will have to have a integral flow check or a check valve of some kind to prevent one pump that is running from just pumping the water back thru the other. Then get an alternating switching relay, IE when it's energized circuit A in use, next time it's energized circuit B is in use, next time energized circuit A is use, etc. Get a low pressure diaphragm switch like used to control a well, plumb the switch into your loop, when one pump quits the diaphragm opens and closes the circuit to the relay and it switches to circuit B which will then run the second pump. One drawback I see to this is if the power goes out when restarted the other pump will run so it's not like you'll have a brand new pump as a backup as each time the power is turned on or off the relay will switch.
I have a low pressure diaphragm in my setup, the controller for the dampers is not energized until the pump is running and X amount of pressure is reached then the diaphragm trips and I get power to the damper controller. I did this in case of a pump failure or a major leak that would cause et pump to suck air, no pressure, no controller then hopefully no boil overs.
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You could always insulate around the lines even temporarily to give you more time to switch out pump or cartridge.
Keep it simple I agree. But also heard the old " Hope for the best - plan for the worst". If you have a pump on hand and a generator available it sounds like you'll be fine Kenny. At least in this situation. ;D
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Ya, Crow, first thing I thought of was an electric blanket type affair to wrap around the exposed lines.
Then I thought just quick drain the lines and service the pump.
All this depends on being home.
If I'm out to town [-30 -40 ]....who's gonna drain it or plug in the electric blanket. :o
Would freeze real quick .
I like Mr Wilson's setup with two pumps running.
I could un plug when home, plug in when it's cold,,, and I'm outta the house?
Cost of running another Taco 011????
They probably kept it simple at Chernobyl :bash: :bash: in 86
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So far, my idea seems to be overkill :bag:
Well, simplest way I see of doing this is to get another pump the same size as the one you have now, install a tee before and after the pump, plumb both pumps in so they are side by side, both pumps will have to have a integral flow check or a check valve of some kind to prevent one pump that is running from just pumping the water back thru the other. Then get an alternating switching relay, IE when it's energized circuit A in use, next time it's energized circuit B is in use, next time energized circuit A is use, etc. Get a low pressure diaphragm switch like used to control a well, plumb the switch into your loop, when one pump quits the diaphragm opens and closes the circuit to the relay and it switches to circuit B which will then run the second pump. One drawback I see to this is if the power goes out when restarted the other pump will run so it's not like you'll have a brand new pump as a backup as each time the power is turned on or off the relay will switch.
I have a low pressure diaphragm in my setup, the controller for the dampers is not energized until the pump is running and X amount of pressure is reached then the diaphragm trips and I get power to the damper controller. I did this in case of a pump failure or a major leak that would cause et pump to suck air, no pressure, no controller then hopefully no boil overs.
This is a little over my head,, gotta read it over a few times ..
The other question I had was,,, would the impeller of the seized boiler pump, restrict the water flow enough,, to make the whole, inline extra pump,, useless.
I guess thats why Martin hooked the pumps up in parallel ??????
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I agree -> KISS, is the way to go
As long as you have a back up pump available, i.e. on the shelf you should be fine. BTW, why travel when its -40 c/f that is too cold to be outside
Definitely too cold to change a pump....... ;D
Fingers would fall off.!!
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I agree -> KISS, is the way to go
As long as you have a back up pump available, i.e. on the shelf you should be fine. BTW, why travel when its -40 c/f that is too cold to be outside
Definitely too cold to change a pump....... ;D
Fingers would fall off.!!
Ayuh,.... Is the plumbin' in the house, as low, or lower than the bottom of the boiler,..??
You can put yer pumps Inside, 'n not have any on the boiler,...
Warm hands changin' it,... ;)
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You can put a 2nd pump in series for a backup and it doesn't cause that much restriction. Water flows through fine when it is off.
You could put a strap on aquastat on it so it only runs when the water line cools. If you put it on the return line it could even be set to come on if you have big temperature drop under load.
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Good answer RSI, I was thinking the same thing!
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Thanks guys. :thumbup:
My next concern would be if one of the inline pumps seizes would it restrict the flow enough to make the whole excercise not worth doing.
Gotta look at the pump internals.
Bondo, I like the idea of the pump on the back of the boiler.
And I still want a backup pump in the basement.
Only thing stopping me is flow issue from seized impeller???????????
Gonna look for schematic.of taco 011
kk
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Unless todays pumps are not what they used to be, I think you're getting worried over something that could never happen.
15 years on my original Grundfos. But like I said, maybe even Grundfos is not as good as they were?
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Water quality can make a big difference on how long a pump lasts. Some go out way sooner than that.
Water will still flow through the pump ok even if it was frozen up. Something with the type impeller like Grundfos uses would be better for the pump that is not normally running. The type of impeller that Taco uses will probably cause more restriction. 1st pic is Taco, 2nd is grundfos.
(http://s3.supplyhouse.com/images/products/zoom/007-042rp-7.jpg)
(https://www.patriot-supply.com/images/large_Grundfos-526062-Webshot.jpg)
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Thanks,, that's what I wanted to hear.
If the impeller is seized stiff, water can still be pulled through by a second pump down line.
I'm probably gonna do it.
It's like having an extra pump on the shelf.
Who doesn't recommend that??
It's already hooked up,,, and ready to roll.
Thanks rsi
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Thanks,, that's what I wanted to hear.
If the impeller is seized stiff, water can still be pulled through by a second pump down line.
I'm probably gonna do it.
It's like having an extra pump on the shelf.
Who doesn't recommend that??
It's already hooked up,,, and ready to roll.
Thanks rsi
Ayuh,.... The only thing I'll add is,.... Over the last few years, since I discovered 'em,....
I've switched out my pump flanges to the ones with the built-in ball-valve,....
Changin' a pump is a breeze, with maybe a cup of lost water,...
No more system drainin', just to swap an entire pump,....
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No draining to replace the cartridge. [at the boiler anyway]
https://www.youtube.com/watch?v=E0X8m0BGZ1g (https://www.youtube.com/watch?v=E0X8m0BGZ1g)
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When I installed my owb 15 years ago, the dealer told me to put the pump in the basement. He said that if it goes out it won't be when the temp is in the 30's. I did and never regretted it. I did have a Y strainer in the line before the pump and the cartage went out almost once a year. Dealer told me to remove it and keep the pump running year around. Since I did this, the pump has never died in the last 4 years running non stop with no filter.
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The restriction by the strainer burned out the pump??????
This is interesting...
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Most likely it did. These pumps can not have negative pressure on the inlet if you want them to last very long. That it the reason it is usually better to put at the back of the stove. In the house works ok as long as water flows to it without it needing to suck.
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Once again, thanks for that . :post:
So leave taco 011 on the back of the stove and could I put a smaller gpm,, less restrictive,, Grundfos in the basement unplugged and ready?
[Suggestion for second pump]
It ciculates fine now,, so just for backup?
kk
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It depends on what you have in your system. A Grundfos 15-58 should work fine but if you want it to be able to run for a fairly long time till you would get around to swapping the other, you may want to just go with a 26-99 since they can be found cheap right now.
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Martin says they last 15 years ........
even I would get it changed by then :bag:
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Ya something cheap,, but I don't want to jeaoperdize the circuit.
It has to work and be less restrictive.
I would turn it on when I was away,, or put a hydrostat on it ...
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But if it is too small it would be fine for a few days but not for extended period of time. You would just have a much lower flow rate when it was running by itself.
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Ok I get it .
As long as it flows till I can change it. at the stove..
Thanks for all the help!