Second floor considerbly colder than first floor.

Sweet_Lew

All,

Wanted to see if anyone could shed some light on this. Last year, I removed the old mercury t-stat from my gas fired hot water boiler system. Once I did that I noticed that the upstairs was colder than before. I swapped out that POS and installed a Honeywell Focus Pro model and ran it this past week and got the same results. Just had the boiler checked out and everything looked good. The only issue was the the pipe that leads into the auto-fill valve needed to be replaced (galvanized pipe rusted through).

The only things I could think of is that it's the t-stat or the uninsulated pipes ( The basement is also not insulated). Maybe the pump is going?

Any ideas? It seems that the water is cooling off quite a bit before it reaches the upstairs. I'd like to be able to sleep without a space heater AND the house heating system.

Thanks for reading.

Lew

BobbyG

things to check

do you know what temperature difference you had between the boiler inlet and outlet when things were working properly.  Generally you see anywhere from 10-30 degrees difference.  If you have any way to see exactly what the temp. difference is now.

Another thing, maybe there is air bound up in the second floor where the circulator doesn't have enough umphhh to move that air.

Sweet_Lew

No air in the system

Thanks for the reply. I bled the radiators last week. Only one radiator had air in it. The upstairs bathroom. I do not have water temps to provide. My system is very basic and worked great up until I replaced the t-stat. I'm going to try something. The old t-stat ran longer cycle  times. More like 2 CPH. I changed the setting on the new t-stat from 3 to 2. I'll see how that works. It does seem like 3 CPH is too short to get the water heated up and circulated for my system.

JStar

?

Do you only have the one thermostat or separate zones?

Sweet_Lew

Correct

One t-stat. Wondering if I could have a separate circ pump installed for the upstairs. But first, I need to figure out what the problem is. I still have my old mercury t-stat. Wondering if I should put it back in.

Brad White

Dopey Question

What is the system pressure at the boiler and the system highest elevation above that? There should be at least 5 psig at the top of your system.



I see where you say, "no air in the system", but where does the expansion tank connect relative to the circulator?



My supposition is that the system is filled to the top but barely any residual pressure and with the expansion tank on the discharge side of the circulator. When the circulator goes on, especially if it is a high-head circulator, it can draw a vacuum and pull the water down below the radiator level in at least some of the radiators. I suspect you would hear something, it is a stretch, but thought I would throw that out there.



For a two story house, 12 psig ought to do it, at the boiler. For three stories, 18 psig.

Sweet_Lew

HMMMMM

I can answer most of your questions. Cold, the pressure reads 15psi at the boiler. The expansion tank is a newer bladder type and from what I can see, it's connected off the water feed line (to the auto-fill valve). I've attached a pic of the setup. Not sure what pressure is on the second floor. If it helps, the pump is a Taco 007-F5.



On a side note, I just bled the radiators again 2 weeks after the boiler was serviced. There was more air in two of the upstairs radiators.



Thanks,



Lew

Ironman

Can you post more...

Pics. showing your near boiler piping? Given the info that you've posted already, I'm thinking like Brad that you might have a pressure, air or pump problem.



Are you sure that the pressure gauge is accurate?



3 things seem to be areas that could have caused your problem because they have been  touched or changed recently:



1. Your thermostat. 2 cph should be fine. If not, try 1 per hour.



2. You just had the boiler serviced. What repairs, adjustments, etc. did they do?



3. The heating season just began. Your pump may be seized and the flow that you're getting is gravity. That's why I would like to see pics. of your near boiler piping, because it appears to be an old gravity flow system with no flow checks.



From a control standpoint, changing your thermostat would have no effect on pump operation. It either comes on with a heat call or not. The thermostat has no separate function to control the pump independently.

Charlie from wmass

Is there a circulator?

I have seen installs out in the Boston burbs with no ciculators. They did not work but they had run for years before anyone complained.

Sweet_Lew

Thanks for the recent replies

Answers for Ironman:



1. I'll change it to 2 and monitor. It's warmed up here so the heat is off at the moment. Pressure was accurate per the heating tech. he attached his own gauge and they matched up.

2. Boiler was cleaned and the system was inspected. The only problem found was the galvanized pipe that lead to the auto-fill valve was rusted through. Just had that changed out by my plumber this week.

3. I'll get more pics up by tomorrow. I'm wondering too if it's the pump. It was making some gawd awful noises at the end of the season last year, but now it's quiet again. Maybe it is seized.



Thanks for all the replies!



Lew

Sweet_Lew

There is a circulator

It's a Taco 007-F5

Charlie from wmass

get a cartridge or a new circ then

That may be the issue. Also try the 1 setting as yours is a former gravity system so it has lots of thermal mass.

Sweet_Lew

Roger that!

I'm going to change the CPH from 3 to 2 and see what happens. If that doesn't help, I'll swap out the circulator.



Thanks!



Lew

Sweet_Lew

Sorry

Been super busy. I have more pics of my setup I will post tongiht. Also, it dipped down into the 20s last night here. Had the t-stat set to 72 and the CPH changed from 3 to 2. House seems fairly even with heat. Downstairs was still a tad warmer than upstairs. Checked the radiators upstairs. All were fairly warm except my son's. His seemed cooler than the others (his is also farthest from the boiler). Not sure what's going on. There is no valve connected to his radiator. Maybe an obstruction? Still wondering if the pump is going out.

Paul Pollets

Pump orientation

I'd make sure the circulator was on the supply header pumping away from the expansion tank and "point of no pressure change". That usually solves the problems if the fill pressure is correct (18psi).

Sweet_Lew

18PSI??

I thought the PSI was supposed to be between 12 and 15 when cold?

Ironman

18 PSI...

For anything above 2 stories is required. However, some boiler manufacturers are now specing 18psi min. on their mod/cons. If you're having air or purging issues 18psi may solve the problem even if your house is 2 stories. The only draw back would be if your expansion tank is marginal. Start @ 18psi and observe the pressure when the boiler reaches 180deg. If you're not over say 26psi @ 180, leave it at 18psi minimum.



The cph should be set to 1 for an old gravity flow system even if it has been converted to forced flow due to the high mass of the old piping and rads.

Sweet_Lew

Thanks!

My house is two stories (3 if you count the basement I guess). I will up the PSI now. Wife took the camera.. =/ Pics will be up tonight. So you all think it's an converted gravity system? It would make sense. The house is from the late 1800s\early 1900s. Don't think there were pumps when the system went in...Whenever that was..

Sweet_Lew

Update

I found the instructions on B&Gs website. Loosen the jam nut and turn the screw clockwise. Adjusted. Thanks for all the help. I'll let you know how everything is tomorrow. Gonna be int he 30s tonight!

Sweet_Lew

As promised

More pics. One thing I noticed. I have an electric damper, but no draft hood. Is that OK to not have a draft good?

Ironman

Draft Hood

The open slot in middle, front is the draft hood.



And yes, you do have a converted gravity flow system.

Ironman

Just Noticed...

From your pics, there doesn't appear to be an air separator on your system. Many times on old systems, they piped the expansion tank so as to let air enter into it from the top of the supply header. Whenever your diaphragm ex. tank was installed, you lost this function and an air separator should have been installed with the new tank.



 Or the other scenario could have been that there was an old open tank in the attic with the gravity flow system that was disconnected when the system was converted. In either case, you should now have an air separator installed or you'll be bleeding air frequently.

Sweet_Lew

Thanks for the replies

You are right. I don't have an air eliminator\separator. When I asked the heating tech if I should have one installed, he kind of blew it off. Again, far as I know the system has been this way for almost 10 years and no one seemed to have an issue.



Also, I'm unsure of where the draft hood is on my system. Shouldn't my setup look like this:

Ironman

Draft Hood

No, The draft hood is built into the boiler. The opening in middle, front of the boiler is the bottom intake of the hood.



Also, proper hydronic design involves air elimination. Your tech might want to spend some time here on the wall.

Charlie from wmass

Just because no one complained

does not mean it was installed properly. Without an air eliminator it means you need to hope the air gets caught in your radiators and then removed manually. The pump may also be plugged up from rust from the old gravity system. The water never moved around it very fast for at least 60 years before they installed a pump on it. Your boiler may also be experiencing issues from all that cold water going through it. By passes and primary secondary piping are made to reduce thermal shock and condensing in boilers.

Sweet_Lew

Thanks Charlie and Ironman

I understand now. I'll talk to the heating company I use and ask them to get quote me for an air eliminator install. Where exactly should it go?



Ironman, I see what you are talking about now. At least that's one thing I don't need. Appreciate the help.

Paul Pollets

Piping and circ location

As I suspected, your pump is on the return pumping towards the expansion tank, and there is no air separator.  Change the setup and you'll have far better system efficiency.  (and no air in the radiators after the first purge)

Sweet_Lew

Happy Halloweeeeeen!

Thanks for the recommendation Paul. Roughly, what would all this cost me (I know difference places charge different hourly).

Ironman

PAUL

If you compare the first pic at the top of the page with the 4th at the bottom, it appears that the tank is in the return line upstream of the circ.

Ironman

2 Options

1. Leave the circ. and tank where they are and install the air separator in the supply line. This will be the cheaper route.



2. Move the circ. to the supply line and install isolation flanges on it. Install the separator upstream of the circ. with the expansion tank connected to the bottom of it. This will obviously be more expensive.



Sorry Lew, but Dan does not allow us to discuss pricing.

Sweet_Lew

Thanks!

Really appreciate the help on this.

Sweet_Lew

Still cold upstairs - Getting a new pump.

Bringing this back. Son's room is still cold. Rad is the coolest in the house. I'm going to consider looking into zoning the upstairs next summer, but until then, I want to change out the pump to something with more OOMPH. Now, I know there are endless discussions on which pump is best. I've read B&G vs. Taco vs. Grundfos numerous time. I wanted to get some of the Pros opinions from this forum.

Jean-David Beyer

New pump.

I am not a pro, but I advise against getting a new pump until you can establish that you need one. While we cannot discuss prices here, I know they are expensive enough thatI would not choose to add or replace one on speculation.



I would think you would like to know for sure that there is no air in the system. If there is, you would prefer to get it out either with bleeder valves or a good air separator (or both). ALso if you are pumping into the expansion tank, that is a good way to invite air into the system.

Sweet_Lew

Don't know what else it could be

Thanks for the reply. I've bled the radiators three times already this season. The same two rads are the only ones with air; the 2nd floor bathroom and my sons bedroom (2nd floor). The bathroom is by far the hottest rad upstairs. My son's is the coldest and also the farthest from the boiler. There's always a chance the plumbing is corroded inside too.

 I'm going to try this. I'll bleed the rads again. If I get air from both of the rads, I'm going to call for  service and see what they think. Maybe I will need to flip flop the setup or just put in an air separator before changing out the pump.

NRT_Rob

if you definitely have air problems

I don't know that I would replace the pump until they are fixed. of course, the air problems might have killed the pump already as well if it dead headed.



I second the "move the expansion tank to the suction side of the pump" and "add air separation" suggestions.



It's pretty easy to see if a pump is working as well. take the head off and see if it spins when you turn it on. or if you can get a "spindicator" it will show if the pump is turning.

Charlie from wmass

Just a few thoughts more

Is the boiler of the right size for the system? Also water is lazy, are there any balancing valves? The water may be pumped around there at 20 gpm and still not go to that radiator because it is easier to avoid it. Lew I think you need a pro to look at the big picture here in person. If you over size the pump and hit that boiler with too much cold return water you can either cause it to condensate and rot out or cause it to have a thermal shock and crack. You could do this spend the money on the pump and then have every radiator cold while you wait for a new boiler to be installed. If this system had been an open system with an expansion tank in the attic pumping faster may blow lots of debris around which will wreak havoc with any water lubed pump you install.

Sweet_Lew

Thanks

I'll get them out next month and see what they say\recommend.

tim smith

Re: flow problems etc

With this being an old gravity system and not being an overhead feed? which is what it looks like from the pics. The 15 psi should be enough. ? are your radiators old cast iron upright radiators.  Assuming appx 7ft from boiler to 1st floor, another 9ft from 1st floor level  to 2nd floor level + appx 3ft for radiators on 2nd floor. I get 19 feet, 10 psi will do 22 feet, plus 3 to 5 psi extra is 15 psi. The pressure looks ok. If they are old large volume cast iron radiators a air separator is not going to do much as the  radiators will accumulate all the air and once he bleeds out, gone. I would probably try for the short term, close down main floor radiators by appx 1/2 at the valves on each radiator as long as old cast iron rads. This may help direct more flow to the upstairs and in turn to the furthest away. You may also have to cut back some of the upstairs radiators a bit too. This is a cheap easy test. (WATCH OUT FOR OLD RADIATOR VALVES LEAK SOMETIMES WHEN THEY HAVE NOT BEEN TURNED FOR A LONG TIME). I have had to cut radiator valves down almost to 90% closed to redirect flow as they are not a good balancing valve and they still let forced flow by to heat the radiators now that the system is pumped rather than gravity. This works to help identify flow problems and also will work until someon opens valves again and screws up flow all over again.  

 Ps, this does not work very well on baseboard or steel panels. 

 One last question, are all radiators the same type or are some of the radiators totally different like baseboard or steel wall panels that use to be cast iron old style. This will screw up heat every time if the don't pipe as separate zone when mixing types of radiation.  Good luck. Tim 

Sweet_Lew

Info

Hi Tim,



Thanks for replying. Yes, old cast iron rads. All different shapes and sizes. What you are estimating is pretty much dead on. I've only bumped the pressure to 16PSI for now. The largest rad is roughly 5 ft high by 4 feet wide. That one doesn't ever get air in it. Only the two upstairs. Unfortunately, I cannot adjust any of the valves. Only 4 of the of the 8 rads have valves and they have all been painted over. Only one valve turns and that on the kitchen radiator. Which is the farthest from the boiler on the 1st floor.

tim smith

Re: valves etc

 Lew, I would really consider getting valves repaired/installed/replaced as needed. Especially on the main floor ones. Would at least give you a fighting chance. Tim