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Re: hot water circulation problem

you were right about the circulator pump- its a bell and gossett series 100.

the boiler is a weil-mclain
uses natural gas
according to the label on the inside cover:
"INPUT- 360,000"
"OUTPUT- 288,000"

there is a shutoff valve just above the et's. if you look at the close up pic of both tanks, follow the copper tubing up. its about 8 inches up.

how would i go about figuring out the "ballpark" figure of the water in the system? there are no radiators in the basement. the first floor is a storefront with 2 cast iron radiators. it also has 4 baseboard radiators.2nd floor has 7 cast iron radiators, as does the 3rd floor. they all vary in size.some are quite large. the house itself is fairly large. about 3000 square feet, not including the basement. im thinking it may be over 100 gallons.

would you suggest moving the et's so they are hanging upside down or straight up? this can be done fairly easily.

but according to the sizing chart, i should be using the SX-30?

jack, i just want to thank you for all your help. the tips and information have been a HUGE help in trying to find the culprit here, and hopefully i will have this resolved before winter really gets here.

Re: hot water circulation problem

Thank you for the additional info.

In a system at 288k btu/hr, all the charts on the Flexcon, Watts, & Amtrol sites are recommending an ET with 14 gal. volume, instead of the 9 combined gal. ET's you have now.

But you can probably just add a few pounds of air to each of your ET's & they might well work.

The ET's can be mounted vertically or horizontally; if they are mounted horzontally they MUST be supported by steel strapping attached to the floor joists, so they don't fall if they should fill with water.

The charts on the Watts & Amtrol sites I listed are based on the standard amount of water a cast iron radiator and boiler system of that size usually contains.

They don't recommend using the total water volume of the system as a sizing procedure in these cases since it is difficult to determine the amount of water in each of the radiators.

They also recommend that the ET connection to the system should be made to the SUCTION side of the B&G pump so that the pump is "pumping away" from the ET.

It's often connected just the opposite in many systems, & this can also cause a rise in system pressure because it lets a little water & unwanted air in via the pressure reducing valve due to a pressure drop at that point (this, however, depends on exactly how the components are connected, and tends to vary from boiler to boiler).

The B&G site has a section called "Pump it UP" under the "Diapraghm Tanks' heading that is very informative.

I wonder if you could draw a diagram of your boiler system if you get a chance, take a photo of it then post it; this need include only the boiler and the immediate piping & components attached to it.

If you could note where the main supply pipe comes out of the boiler (usually at the top) & what is connected to it (water suppy, reducing valve, ET's, air vents, air eliminator, etc); and also include the main return pipe as it goes into the bottom of the boiler, with the B&G pump connected.

Where & how these components are connected greatly determines system pressure, air in the system, etc.

The Radnet site has a Watts site citation that is helpful in sizing ET's.

Watts has free 800 technical help numbers at 1-800-542-1682 and 1-800-476-1682.

Additional help can be obtained by contacting "The Wall" at heatinghelp.com and the "boiler help" site at doityourself.com-->plumbing--->Boilers.

The larger ET's like the Watts ETSX-40 are floor models that cost over $100, so try to work with the 2 ET's you have now.

Old Man
Re: hot water circulation problem

Jack you use the term "water logged" please define this in this context.

Re: hot water circulation problem

Waterlogged refers to the tendency of expansion tanks to completely fill with water in a hydronic system.

When this happens, the boiler water when subsequently heated has no place to go, and pops the pressure relief valve to dump water on the boiler room floor.

Waterlogging occurs most frequently in the older, oblong steel expansion tanks that have no pressurized bladder, but can also happen in bladder-type ET's when the bladder fails.

Re: hot water circulation problem

hey jack, i just want to thank you again for all your help. i know its been a while, but things have gotten really hectic around here, with the holidays coming and having 3 girls. a couple of weeks ago, a friend and i did some tests on my heating system and found out that i had gotten a faulty prv AND innacurate dual gauge! what are the chances of that? lol! turns out the plumbing supplier across the street from my house had gotten a batch of bad prv's from B&G which were set to 20 psi. after we changed it with a new one, thats when we realized the pressure gauge was 5 psi off. with the new equipment in proper working order, we then tested the system again,and realized the et's werent getting hot. we took one off to check to see if the valve was working properly, and it was, but there must have been a blockage that we flushed out because now they are working good. i really want to thank you again for all your help as it was very informative, and i dont think i could have done it with out your help.

Re: hot water circulation problem

Good job!

Anyone who can hang on a boiler problem as long as you did deserves all the praise in the world.

I'll say a little prayer that your heating system will be trouble-free for the rest of the heating season.


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