indirect hot water noisy, and cold (lukewarm)-help!

rattle

I had a new weil-mclain steam boiler installed a little more than a year ago.

Steam heat (1 pipe) works well and we are happy with the quality of the installation.

The hot water was an issue last year and is again.

When there is a demand for hot water (i.e. a shower), there is a loud rattling from the water tank that lasts for almost a minute. This occurs when the oiler is running AND when the boiler is off, but hte boiler water is still hot.

After one shower, there is still only lukewarm water available almost a half hour later (unless the heat for the house is on).

This is the tank within a tank weil-mclain gold sgo.

Any thoughts on this riddle are much appreciated!

Dave in QCA

Pictures Please

It would help alot to have pictures of all of the piping connections for the heater, especially the connections at the boiler and where the boiler lines connect to the water heater. 

It sounds like there may be a problem in how its connected.  Normally, that tank can produce a huge amount of water with boiler water in the 150-180 range. 

rattle

picture of piping attached (I hope)

/Users/chrisledwick/Desktop/P1040454.JPG

kcopp

The rattle is ....

most likely a flow check that is moving around w/ the flow. The circulator really should be a 3 piece type (series 100 or taco 110) and there should be some bypass piping to direct some of the flow back to the boiler so that you don't flash to steam. An reverse acting  aquastat would also be a good idea to keep the boiler from steaming in the summer on a long draw. There could be a bunch of junk in the bottom of the outer tank preventing heat transfer. Was the boiler HW piping flushed recently?

ctjomac

The pro's will weigh in this evening

In the meantime I'll offer up a novice perspective:

1:Is the boiler hot water pumping into or out of the bottom of the boiler? 2: The pump should be a 3 piece design...the one installed will not last long at all. 3: The is probably air space in the top of the storage tank, especially being a tank in tank design rather than a coil in tank design. 4: Does the problem only happen in the winter? I ask because I don't see any piping between the return of the tank to the supply of the pump. If you don't have them tee'd together with a throttling valve the water going to the tank will likely exceed the 200 degree limit on the tank in tank designed heater. You should actually be blending the water from the outlet of the return to the suction side of the pump. This will lower the water temperature going to the indirect.

Because you are getting noise and lack of supply I think you have air in the top of the tank and probably noise from excessive boiler temperature(would hold true in the winter when heating the house)....Joe

Dave in QCA

More pictures please

Which way is the pump pumping.... to the boiler or away.  It looks like it is connected to the bottom of the boiler and to the top of the tank.  Where does the other pipe connect? 



Need more pictures, more angles, up close of connections too.  Just can't see what is going on from your one picture.

Jean-David Beyer

Why two flow-checks?

I am a homeowner and I have a W-M (Triangle Tube) hot water heater like yours. The hot goes into the bottom and return comes out the top. Since my boiler is an Ultra 3, the hot water comes out of the top of the boiler and drops down to the bottom of the indirect. This drop is a heat trap, perhaps accidentally, so no flow check is required there. I do not know if your drop is enough to be a heat trap. My circulator is a Taco 007-IFC; i.e., it does not have a real flow check valve in the return either, but there is no convection flow anyway, so the little spring check is enough.



It is my understanding that circulators like the Taco 007 do not work well with steam boilers because of the deposits that build up.

Jean-David Beyer

air space in the top of the storage tank

I cannot see it, but there is supposed to be an automatic vent valve in the top of that indirect that lets the air out. Like a Taco Hy-Vent. It screws into the top of the tank right in the center. If the little cap is screwed down tight, it will not release the air.

Dave in QCA

Steam Boiler

Jean-David, this application is quite a bit different than yours because it is running off of a steam boiler as compared to your Ultra water boiler.  There are a number of considerations that have to be dealt with here because the boiler water level is much lower than the boiler water in the outer tank of the heater.  Thus, there is a necessity of check valves.  It is also critical in how the piping is connected at the boiler and the heater.  Once we have a clear picture of how this one is piped up, we can look at the manufacturer's installation instructions and see 2 things.  First, why it is not working, and second, how it's supposed to be connected.

Jean-David Beyer

boiler water level is much lower than the boiler water in the outer tank

I did not notice -- appreciate -- that the water level was higher in the indirect than in the boiler. In fact, I imagine the air vent normally required at the top of the indirect would have to be removed and replaced by a plug so that air would not enter there. In fact, purging that loop looks impractical.



Option 1, that is probably no good, is to raise the boiler height until its water level exceeds the height of the indirect.



Option 2 might work: put a heat exchanger between the indirect and the boiler. Keep the heat exchanger lower than the water level of the boiler. Trouble with this is the cost of the heat exchanger and additional circulator, though the additional circulator would not need to be a 3-piece one. Plus a means to fill that loop with expansion tank, pressure reducing valve, etc., is a lot of painful complexity.



I hope there is an option 3.

rattle

more pics and info!

rattle

view from the front

previous pic is of the installation diagram

rattle

top of tank

notice that the factory air valve was replaced by installer with this valve last year after this issue first arose

rattle

last pic-unless you need a close-up of something else

Thank you to all who responded to this issue-I like the idea of the airlock and the mixing before entering the tank.

It is worse in the heating season-I think it only happens during the heating season, actually.

The pipes were installed the reverse of what is shown in the diagram-they were switched when I offered that I thought that might be the cause of the limited hot water. The pump was left and it was explained that pulling the water out was the same as pushing it in...

Not an engineer, so I just nodded my head.

rattle

those pipes

the "pipes" I was referring to in the last post are the supply pipe to the water heater and the return to the boiler.

ctjomac

If it's happening during the

heating season only you should really look at installing the bypass between the return from the tank to the supply of the pump ro lower that temperature going into the indirect. In the winter you are exceeding the maximum temperature going into the tank. Then look at seeing if air in fact is in the top of that tank...I bet at some point in the last 2 years the water level of the boiler dropped just enough to get alittle bit of air on the loop and caused the pump to cavitate and you have an air chamber up there. hat would also account for not having enough capacity(in the winter).

rattle

this is starting to sound pretty good

I like this idea-is this something pretty straight forward that a non-steam pro (regular heating plumber) could do?



Also, I am concerned re: the placement of the pump-pulling water out, rather than pushing it into the indirect. Is that a huge issue or otherwise something that should be addressed while installing the bypass?



Lastly, should I get the original air vent put back? not sure how to purge or release the air from the aftermarket piece.



At this rate I may have to send out lobsters and/or Maine beer to the winning solution.

STEAM DOCTOR

Air

I would bet that there is an air issue. Are there any purge valves(i.e. valves that you can attach a hose and let water out/in) on the black pipe going from the boiler to the tank? There should be on on each black pipe close to the boiler. If not then there is certainly air in the tank. Can you take pics of the points that those black pipes connect to the boiler?

Steamhead

That's the wrong type of indirect

for use with a steam boiler. You have a "tank-in-tank" type which requires a few pounds of pressure to fill its outer tank, where the boiler water is. A steam boiler cannot provide this type of pressure. A hot-water boiler can, so that's where a tank-in-tank unit works very well.



What you need is a coil-type indirect where the coil is entirely below the boiler's waterline. We like the SuperStor Ultra units for use with steamers. With a proper circulator- a 3-piece oil-lubricated bronze one- this unit will work properly with your steamer.



Whoever put that in needs to fix it at his expense.

STEAM DOCTOR

?

Good eve Frank. Not questioning your vast expertise at all. Just wondering why you cant pipe the indirect the same way that you would pipe any hot water loop that's above the boiler water line?

Rod

Manual says Okay for Steam

Frank- Unfortunately it would seem that Rattle is in a bit of a bind here .  i checked out the manual (Attached)  and on Page 45 is the suggested piping setup for systems with steam boilers. If the piping is done per the diagram, what's likely to go wrong? Can this type of boiler (tank in a tank) be made to work ?   If not, any idea of the best approach to take?

- Rod

Jean-David Beyer

on Page 45 is the suggested piping setup for systems with steam boilers.

Reading page 44 looks like a good idea too.

Steamhead

That indirect was made by Triangle Tube

it is similar to their Phase III Smart units.



Some years ago, I contacted TT to see if their Smart units were suitable for use with steam boilers, since the I&O manual for these units did not mention hooking them up to a steamer (still doesn't). We had used them on hot-water boilers and liked them a lot- still do- but the lady I spoke to said they were NOT recommended for use with steamers, for the reasons I cited earlier. She actually steered me toward the SuperStor- an honest gesture if there ever was one, since (AFAIK) TT and Heat Transfer Products have no corporate connection, and are therefore competitors.



Why W-M put a steamer hookup in the I&O for a tank-in-tank indirect when the actual manufacturer of the indirect did not recommend it be used that way is anyone's guess.



Now, I'm not saying it's impossible to make a tank-in-tank indirect work with a steamer. But without the standing pressure sitting on top of the water to keep it from flashing to steam, there's a lot greater chance of problems. I say again: That indirect is not a good choice for use with a steamer, and if we were doing that job we would not have used that indirect.



The newer W-M AquaPlus is a coil-type indirect, and as long as the coil is completely below the boiler's waterline (as shown in the I&O manual) it should work fine with a steamer, when properly piped.



Here is the I&O for the TT Phase 3 SMARTs:



http://www.triangletube.com/documents/2/Smart-PhaseIII-TR-Manual.pdf



and for the Aqua Plus:



http://www.weil-mclain.com/en/multimedia-library/pdf/weil-mclain-pdf/products/water-heaters/aqua/aqua_manual.pdf



and the SuperStor Ultra:



http://www.htproducts.com/literature/lp-83.pdf

rattle

are they separate problems?

Does it sound like the two issues are unrelated?



Is it worthwhile to do the bypass/mixing plumbing solution to address the overheated heating season boiler water while keeping the indirect?



For the possible air in the tank, can that be purged and filled with water as needed on a maintenance schedule for the homeowner (me)?

Charlie from wmass

As Frank said

Wrong tank for the job. Piping needs corrected as stated already with a bypass and a three piece circulator. Lack of hot water is due to low boiler water level in the outer tank and poor flow due to air lock when the circulator is trying to push the water. Get the right tank piped in properly with the right circulator and then you will be in hot water the right way.