specific hot water radiators not working

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jpenns

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Hey all, thanks in advance to anyone reading this or offering advice.

I have an old 2 1/2 storey house with hot water heat. The main floor radiators all heat great except for one in the front corner of the house. The 2nd floor radiators also all heat great except for the one in the bedroom in that same corner. There's only one radiator on the third floor, and it is right in that same corner, so of course, it also isn't heating. I have bled all the radiators, from bottom to top (not sure if the order matters). I've read that the pressure should be at 18psi for a 3 level home, mine is at 20. That's about the extent of my troubleshooting knowledge at this point. Anybody got any ideas?

Thanks again!
 
Hey all, thanks in advance to anyone reading this or offering advice.

I have an old 2 1/2 storey house with hot water heat. The main floor radiators all heat great except for one in the front corner of the house. The 2nd floor radiators also all heat great except for the one in the bedroom in that same corner. There's only one radiator on the third floor, and it is right in that same corner, so of course, it also isn't heating. I have bled all the radiators, from bottom to top (not sure if the order matters). I've read that the pressure should be at 18psi for a 3 level home, mine is at 20. That's about the extent of my troubleshooting knowledge at this point. Anybody got any ideas?

Thanks again!

Your right the pressure should be up some in a three store, Was this system working before? and has anybody changed the pump. Is the heat all on one stat so they all heat at the same time. I lot of these small pumps do not have enough head pressure to use them in a 3 story home.. You should use a higher velocity pump with more head pressure. do you know is your system,
a loop, reverse return or one of the old monaflow systems. paul
 
Thanks for your reply. I've now discovered one other radiator on the 2nd floor isn't getting heat, in the opposite corner of the house.

The system hasn't always worked properly, mainly the 3rd story has had issues, but I'm pretty sure the 2nd floor rads all worked at one time. I got the house a couple of years ago and it's been a gradual process of learning about the system and trying things though, with several rads not working at one time or another. The expansion tank has been replaced, but I don't know about the pump. It was originally gravity circulated, so the pump was obviously added at some point. I don't know the system type, but from the boiler there's a main hot water line which branches out to different areas of the house, and from there the lines feed one or more radiators. Then there are separate return lines which branch identically. Does that describe it?
 
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Thanks for your reply. I've now discovered one other radiator on the 2nd floor isn't getting heat, in the opposite corner of the house.

The system hasn't always worked properly, mainly the 3rd story has had issues, but I'm pretty sure the 2nd floor rads all worked at one time. I got the house a couple of years ago and it's been a gradual process of learning about the system and trying things though, with several rads not working at one time or another. The expansion tank has been replaced, but I don't know about the pump. It was originally gravity circulated, so the pump was obviously added at some point. I don't know the system type, but from the boiler there's a main hot water line which branches out to different areas of the house, and from there the lines feed one or more radiators. Then there are separate return lines which branch identically. Does that describe it?
If you had a gravity system that means your pipes are large. When you bleed air out, you have to do it when the pump is running, then turn off pump and bleed it for a long time with pump off. Gets air out better that way, and keep that pressure up there.. Can you get me no. off the pump. can you start taking pic and send them to me. You can send them to [email protected]. Are your radiators small baseboard or tall cast iron?
More info and we will see if we can help you out. Paul
 
Awesome, thanks. Getting the pump on and off is as simple as turning the thermostat up and down to call for heat, right? I had actually done a longer bleed yesterday on the 3rd floor and now have some heat there so I'll bleed it some more and hopefully get to full bore! I'll also email you some pics. Thanks a ton!
 
Awesome, thanks. Getting the pump on and off is as simple as turning the thermostat up and down to call for heat, right? I had actually done a longer bleed yesterday on the 3rd floor and now have some heat there so I'll bleed it some more and hopefully get to full bore! I'll also email you some pics. Thanks a ton!
I got you pic. Nice looking radiators. Is there a bleeder at the right end of all the rad.? Are the 1/4 turn valves on the rad. all open?
I need to know how many rad are in your system?
What does your pump measure with out the flanges 6-1/2?
You can bleed more but you may still not get it to work right. If that pump is just a standard pump and not a HV (high velocity) then it will not do the job.
A standard pump is made to pump about 8 gal. of water a min. Your rad. should be moving one gal. per. min. through each rad, That means 12 Rad. pump needs to pump 12 gal. per. min. at the head pressure you have. How far is it from top of boiler to top of rad. on the upper story. Are you with me so far? . A lot of young service tech make the mistake and don,t use the right pump.. Is your pump a 3 speed, if so what speed is it on?
Now if you look at your pump you will see it has a check valve built into it.
If you don't have a flow control valve up by the ceiling then the new pump will have to have this check valve. If you do have a flow control valve the it should be open so you are not asking your pump to open two check valves.
Would like a few more pic. just above the boiler and some of the piping system. I hop you under stand all this i have talked about. Get back with me.

Paul
 
A bunch of homework for me! :) Here are my answers.

There are bleeders on the ends of all rads. Not always the right end though.

Yes the valves are all open, at least on the ones that are not heating. The ones that are really hot I've closed a little bit.

There are 10 rads total. Used to be 11 but one was taken out.

It's 26 feet from the top of the boiler to top of the highest rad.

I believe I have a flow control valve, is that what regulates the pressure of the water coming into the system, from the water input pipe from the city? I'll email you a picture of it. In any case I can't find anything that looks like a check valve on the pump. I also can't find anything on it that refers to different speeds. How could I find out if this is a HV pump?

I think I follow what you're saying. Since I have 10 rads, really my pump should be capable of pumping 10 gallons a minute?

I'll email you pictures of the pump with measurements.

Thanks so much!
 
A bunch of homework for me! :) Here are my answers.

There are bleeders on the ends of all rads. Not always the right end though.

Yes the valves are all open, at least on the ones that are not heating. The ones that are really hot I've closed a little bit.

There are 10 rads total. Used to be 11 but one was taken out.

It's 26 feet from the top of the boiler to top of the highest rad.

I believe I have a flow control valve, is that what regulates the pressure of the water coming into the system, from the water input pipe from the city? I'll email you a picture of it. In any case I can't find anything that looks like a check valve on the pump. I also can't find anything on it that refers to different speeds. How could I find out if this is a HV pump?

I think I follow what you're saying. Since I have 10 rads, really my pump should be capable of pumping 10 gallons a minute?

I'll email you pictures of the pump with measurements.

Thanks so much!
The pressure is regulated with a pressure reducing valve
A flow valve is made to adjust between a gravity flow and a pump flow.
That pump check valve is built up inside the pump, so you can't see it, it says on the pump that you have one.
If your pump was a HV it would say that on the pump, and i did not see that on your pump. When they calculate how much water a pump can pump they consider height, piping, rad. But like i said before i would never use a standard pump on a job like yours. It should be a 1-1/4 HV pump. I don't remember the
height difference. but i think yours is 6and 1/2" tall and a HV might be 7 or 7and 1/2" tall.
Your pump would probably pump 10 gal a min. if you only had one story. but its a real border line case with 3 story and all that piping restriction.
I will look for you pic. Paul
 
OK, I don't think I have a flow valve then, I was thinking of the pressure reducing valve.

The pressure is regulated with a pressure reducing valve
A flow valve is made to adjust between a gravity flow and a pump flow.
That pump check valve is built up inside the pump, so you can't see it, it says on the pump that you have one.
If your pump was a HV it would say that on the pump, and i did not see that on your pump. When they calculate how much water a pump can pump they consider height, piping, rad. But like i said before i would never use a standard pump on a job like yours. It should be a 1-1/4 HV pump. I don't remember the
height difference. but i think yours is 6and 1/2" tall and a HV might be 7 or 7and 1/2" tall.
Your pump would probably pump 10 gal a min. if you only had one story. but its a real border line case with 3 story and all that piping restriction.
I will look for you pic. Paul
 
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