Boilers - Steam and Hot Water Systems - can not get radiators to reheat

a brief overview of my home: it is approximately 2000 square feet, two story colonial with a full basement (basements ceilings are 8ft). the home was converted from two pipe steam (reverse return) to hot water natural gas setup. the boiler is a Utica mgb-175hd approx 143k btu. everything is one zone. pump (taco 009) is on the return side. it is plumbed with a bypass controlled by a ball valve that leads into an esbe thermostatic valve (140 degrees) that joins the return. the pump (taco 009) is on the return side. this house is all one zone, first and second floor. the basement has one radiator, controlled by a ball valve with a single pipe supply and single pipe return.
forgetting about that, the house is supplied in a configuration of front and back, each controlled from the supply with ball valves (1 for front, 1 for back) and driven by the single circulator. the front has 4 radiators on the first floor (2 - two foot cast iron radiators, 2 -five foot cast iron), and two radiators on the second floor (1 - two foot, and 1 - five foot). the back of the house has 1 - five foot radiator on the first floor, and 1 - two foot radiator and 1 - five foot radiator. all of that being said, my problem is i bleed the one large radiator (furthest from the boiler)on the first floor on the front side, i get no air just water, and it gets hot. all of the other radiators in the front loop are already hot, and the back loop is hot with no issues.
after i get everything working properly and the boiler shuts down for the night, when the thermostat goes to a lower temp and is not running for a few hours, i cannot get the system to heat the same way, as in the same heat the radiators had before it shut down. should i throttle the ball valves for the front and back loop? what position should the ball valve on the bypass loop be in? any help would be appreciated, i know this is a long read. thanks in advance for any help.

Can you clarify what you mean by "reheat the same way"? Do they not get hot at all? Do only the bottom portions of the radiators get hot? Do the front rads get hot and the back don't?

apologies for being vague. what i mean is when the system starts again in the morning, with both ball valves that control both the front and back of the house completely open as they were when everything was perfectly hot, the radiators on the back side of the house were cold and the ones in the front were warm. another detail i neglected to mention is that the piping at the boiler is 1" - 1 1/2" copper that leads immediately to the 2 inch steam pipes at the ceiling. system pressure is 18-20 according to the gauge on the boiler and temp tops around 180F

Do the radiators in the back ever get warm in the morning? If not, do you have to bleed that radiator again to get heat into it?

i had been keeping the back loop turned off. i opened up the loop last night after i bled the rads with the system off. the back heated up no problem once i started the system last night. the front i had to bleed through to get heat last night. could it be the position of the ball valve on the bypass loop?

10K? must be a 2 wheeler...

I would like to see pics... can ya take some? Might help to better understand stuff.. you can set up a free account at Image hosting, free photo sharing & video sharing at Photobucket (http://www.photobucket.com) and upload the pics there, and place a link in this thread so we can view.

Your ESBE is on the supply side if I understand correctly?

In general, the valve in the bypass line to an ESBE would be OPEN, because the ESBE will 'modulate' based on the water temp, closing almost completely if hot enough.

you hit the nail on the head its a suzuki lol. i can take pictures tomorrow and thanks for your interest in loving my problem. i will open up the bypass fully and let the esbe work. i will be able to take pictures tomorrow, tonight i am working. what bearing, if any, does the type of pipes in my system have on my situation?

GSX?

what bearing, if any, does the type of pipes in my system have on my situation?

TYPE of pipe? probably not much...

SIZE of pipe? maybe a bit... and the resultant large volume of water in your system may play a part as well.

Location of the thermostat relative to whichever loop heats faster probably will also have some effect.

gsxr 750. thermostat is in the living room in the front of the house, but it controls the front and back of the house

im sorry it has been a long delayed, ive been working a lot (fortunately). here are pictures of my boiler. any and all help and recommendations are a greatly appreciated!
http://www.flickr.com/photos/44594749@N05/

to be more specific, my issue seems to be directing the flow. could it be that i need to pump from the supply rather than the return because of the way the piping is set up in the house?

Jeeze, a GSX _and_ a Bronco! Some guys have all the luck! 302 in the Bronc?

Wow, dig them purple pipes!

Here's what I think is happening:

You said the front of the house rads get warm, and that's where the thermostat is.

You've got the ESBE valve... what temp thermostat is in there? probably a 140 I think?

So, the boiler fires up on a heat call and comes up to temp, bypassing most of the flow through the bypass valve. When the boiler hits 140, _some_ of the flow heads out to the rads, and since the water is already AT 140, they heat pretty quickly, and satisfy the thermostat before the back loop heats up.

You asked about the position of the bypass valve, and it's probably correct to have it partially closed... because when it starts to open, it's going to be faced with cold water coming back from the zones which will cool it off and it will move back to bypass... slowly heating the system up. If you did open it all the way, you might not get much flow at all through the system, or it would take a very long time to heat up... you NEED some restriction in the bypass line to force the hot water into the system as the ESBE begins to open. You can't close it all the way though, if you did, the pump would be 'dead-headed', and the ESBE might never open... try closing it some more, but never all the way and see what happens.

The idea here is to force as much of the hot water into the zones as you can when the ESBE starts to open, and before it starts to close... it is fairly slow to react, so there is some time to get the hot water through the loop before it begins to modulate again. If you've ever had that valve open, you know that it's just a car thermostat inside, and you probably know how slowly they react.

A GLOBE valve would be a much better choice for the bypass valve... ball valves really shouldn't be used for 'throttling'... and they are very sensitive to position... almost all of the throttling is going to occur in a very small band of a few degrees of rotation. A good globe valve gives much better 'resolution' for throttling purposes.

I know I'm kinda rambling here... but trying to put what I'm thinking into words isn't easy sometimes! Is this making any sense?

Forgot something I wanted to say...

You might have to consider moving the t'stat to a location that isn't as affected by the front loop... but you would need to carefully select the location. Right now, the front loop gets warm first, and the t'stat satisfies, leaving the back loop cold. If you move the t'stat to where it's _only_ influence is from the back loop, the front rooms would probably overshoot... so you would need to try and find the 'happy medium' for the placement. One that allows the back loop to heat up, while not overheating the front.

Back to the ball valves and throttling... you could try choking down the front loop with the ball valve... I see that one is partially closed already, I'm guessing that's the front loop? Try throttling it down some more...

I mentioned earlier about the difficulty throttling with ball valves... you won't notice much difference in flow until the valve is durn near closed, then the slightest 'twitch' of the handle, and you've gone too far.

As the weather gets colder, you might find you need to fiddle with that valve to restore the heat balance to the home.

Another problem with throttling the loops is that if you slow down the flow too much, you whack the balance of the system all out... by the time the water gets to the end of the loop, the last rads, it's much colder than when it entered, so you now can lose balance within the loop. It's always best to maintain the max flow so this doesn't happen... and zone valves _might_ be an option... if the front loop were to satisfy that thermostat, and the back loop was still calling, you would definitely get heat back there, and prevent the front from overshooting.

You might consider zoning the two loops with valves, and 'stagger' the setback schedules... bring the back loop up first, followed a bit later by the front loop... even if they did both call at the same time, the boiler would run until both were satisfied...

My brain is like swiss cheese... full of holes! I forgot something else...

Looking through the pics, I don't see any air collection, or venting devices? How come no air scoop or auto air vent?

I doubt that moving the pump to the supply side will help with the heat balance in the home, but it would help with air removal, if moving the pump were coupled with addition of an air removal system.

After looking at pics it looks like the new supplu and return is 1" pipe if I'm not mistaken. This could be where your flow problem comes in. You have a two pipe system where the water flows to all rads at once. Your feeding into 11/2" pipe for a reason. I realize it was steam to begin with but your only going to get as much flow as your smallest pipe. If you could picture the old domestic water situations. They used to feed the house with 1/2" pipe and your main in the house was also 1/2 along with the branches to the fixtures. This is basically what you have for your heat. Back then if you ran one faucet you got full flow, but if you turned on another faucet at the same time the flow was cut way down. If you're old enough you would especially remember this if you were in the shower and someone turned on the hot water and you imediately were in a cold shower. If you had a loop system you might get away with it a liile better because the water would have to through one to get to the other. With what you have they try to feed everything at once and I think that's where your loosing your flow. By throttling down the valves you might be compounding the problem. I'm assuming that by-pass valve is so the boiler doesn't get thermal shock when the cold water returns back to the boiler which is a good idea with a high water content system and a low water content boiler, but in your situation it is also taking away from the flo. Just a thought.

I'm assuming that by-pass valve is so the boiler doesn't get thermal shock when the cold water returns back to the boiler

That and to prevent long term condensation problems with the high volume system.

It's a pretty neat device actually, as I said, basically a car thermostat set at 140... starts to open around 125-130, and it's 'all in' at 140.

It's main drawback is that it acts as a SYSTEM bypass, so while the boiler is heating up, there is little to no flow in the SYSTEM, it's all going around the bypass. When it does start to open, and the cool water hits it, it will naturally start to close again... and repeat until the system is also up to temp. So the flow to the system sorta starts and stops in a slow 'oscillation'. Unfortunately, it doesn't seem that in the mild weather at least, the heat calls last long enough to bring the system up to temp.

I agree that throttling might actually make the problem worse... IMHO, this system would benefit from the zone valves I mentioned.

By the way, MOST of the copper you see is from the old installation I think, and it worked OK... BTU-wise, the 1" is probably big enough... [edit: I was thinking of someone else's system when I made this comment... might not be completely accurate statement!]

10K, are all the rads piped with supply and return to separate pipes? what size pipes are going to the rads off the main? I see some that look like 1/2"?

Thanks for all of the replies, and here is what i absorbed from all of it, and please feel free to correct any of my interpretations :

If you did open it all the way, you might not get much flow at all through the system, or it would take a very long time to heat up... you NEED some restriction in the bypass line to force the hot water into the system as the ESBE begins to open. You can't close it all the way though, if you did, the pump would be 'dead-headed', and the ESBE might never open... try closing it some more, but never all the way and see what happens.

What i gather from that is that essentially the system is indeed 'dead-headed' until the ESBE opens if i have the ball valve on the bypass wide open. BTW that ball valve on the supply that is noticeably throttled is the valve that supplies the back of the house. the problem overall is that when i open the valve to the back half of the house some more, the back half heats up perfectly, but i lose heat on the larger radiators on the front half of the house. After all of the description of the operation of the esbe, i feel that it is the ESBE that is my problem, with cold water returning, closing the ESBE and theoretically 'dead-heading' the pump.

Onto the next issue: air removal. Who ever put this system together did it in a cheap manor. There really is no means of air removal. the expansion tank is plumbed off of the elbow that comes out of the supply of the boiler. take a look at the pictures, i was surprised too. there are no mechanisms for air removal beside bleeding the radiators individually.

The copper from the boiler is 1", to the 2" from the steam system, looks like 3/4" going to the second floor riser and at the radiators all of the copper is 1/2". Thanks for the replies guys, i look forward to hearing back.

Also, if this turns into a complete shenanigan (sp?) in the spring im considering replumbing the system. remove the one pump on the return, go with individual zone circs on the supply, and adding a spirovent for proper air removal. my only issue wit hthat, would be that i would want to zone for first and second floor, which i think could be accomplished by using zone valves at the radiators. Again, dont hold back i love the input. Thanks again.

10K, I'm confused again... I thought that the two pipes off the manifold pointing up were for two loops, front and back, on the same floor... I can also see another pipe heading down, with a closed ball valve, and thought that was for some basement heat that you aren't using...

but your last post indicated that there is a second floor, and more heating loops? Pleeze essplane...

10K, I'm confused again... I thought that the two pipes off the manifold pointing up were for two loops, front and back, on the same floor... I can also see another pipe heading down, with a closed ball valve, and thought that was for some basement heat that you aren't using...

but your last post indicated that there is a second floor, and more heating loops? Pleeze essplane...


In my photos looking at photo DSC03294, Yellow valve at top left is the valve which controls the loop for the front of the house, Yellow valve at top right controls loop for back half of house. Yellow valve at bottom center controls the bypass. Home is composed of basement, first floor and second floor. Front loop totals 6 rads, back loop totals 3 rads.

So then the 'front half' and 'back half' are BOTH first and second floors then?

Isn't there another tee on the end of the supply header with a pipe heading downward, and a closed ball valve on it? You can kinda see it in 3304...

thats correct Trooper. front half and back half run up the front and back of the house on the first AND second floors. that valve that you mentioned controls a single radiator in the basement. i figured its best kept off for right now while i try to straighten out the other 98% of the system

OK, I get it now... that's what I thought... a basement rad...

The fact that each loop is UP and DOWN, my idea of putting zone valves right after the ball valves might not work so well then.

And I think that if the back half heats that much faster than the front half, there must be significantly less 'head' in the back loop.

You might could still have some air in the front loop... in spite of the bleeding, especially since you have no scoop or vent. And every time you bleed, you add a little more fresh water which carries more oxygen into the system... catch 22, bleed to take air out, fresh water brings air back in!

Moving the pump to the supply is looking like a better idea all the time! If you raised the whole supply header, you could make room for the LWCO on a vertical nipple right out of the boiler, freeing up some room in the horizontal section for the pump and spirovent.

yeah i agree with the moving of the pump. i think i might begin to accumulate parts to make the switch to circ controlled zones. what is your feeling on controlling rads with zone valves?

More on the ESBE... as long as the bypass is open, you won't dead head the pump...

When cool, the bypass port is open on the ESBE, and the system port is closed (but there IS a small amount of flow through, it doesn't completely 'seal' the other port). Between 125 and 140 (assuming it's a 140F job, is it?) BOTH ports are partially open, above 140, 99% of the flow is through the system port.

But, below 125 there is almost no flow in the system. The idea of throttling the bypass valve is so that when the ESBE does start to open to the system, you get as much flow through there as possible before the ESBE starts to react to the cooler water returning through it...

If the back loop is that much smaller than the front loop, with that much less head, it makes sense that the back loop will heat faster.

i think my major sticking point is still that i cannot seem to get to a point of having the front and back evenly heat.. and yes the ESBE is 140*

what is your feeling on controlling rads with zone valves?

You mean electric zone valves on each rad? I think that would be a major PITA having to run 24VAC all over the place.

Or, do you mean Thermostatic Radiator Valves (TRV) ? (non-electric)

electric zone valves. would only be for 4 rads

Trooper, just uploaded a diagram of the rads to my photo hosting site. the black lines denonte both supply and return to the rads being that both supply and return follow the same path practically

If you wire them up such that they will call the boiler to fire, you will be short cycling to beat the band. Let's say only one rad calls for heat, you wanna fire up a big ole boiler to service just one rad? I'm guessing the 4 you are thinking of are the ones on the second floor?

Take a look instead at the TRVs... they are 'passive', when the room needs heat, it will open up and wait for a normal heat cycle, if the room is warm enough, it will close, whether or not the boiler is still 'servicing' the rest of the loop.

By the way, I scanned back and don't think boiler pressure has been talked about? At least I didn't see it in a quick scan...

What is the pressure on the gauge when the boiler is COOL, and again when HOT ?

well i wouldnt wire them so that the valves themselves call for the heat, but rather the (future) second floor thermostat at which point those zone valves would open and heat would flow. boiler pressure start cold between 14-16 and hot between 18-20.

With zone valves, it IS the valve that calls for the heat. The thermostat tells the valves to open, and the endswitch in the valve activates the boiler when it opens... what you are suggesting is sort of a wiring nightmare...