Hi folks,

I'm a total newbie when it comes to hot water heat systems. Our house was built in 1955, and come with an oil fired hot water system. By and large it works pretty well, but some radiators do not always pump out heat.

Specifically, the baseboard radiators in the basement (very near the boiler) only heat up half the time, and we have 1 radiator in the washroom on the 2nd floor of the house that did not work at all this winter, until it magically started again recently. 2 other radiators on that floor have worked fine. I bled all the radiators at the beginning of the season...

Any advice ? I can post pictures of the rads and/or boiler etc... Actually, I might do that - I would also like to understand what the different parts and valves on the boiler/expansion tank/etc do ....

Thanks!

 

The basement radiator business is interesting to me, because I am not familiar in my experiences with such a situation and wonder what the pipe layout to and from these is like... and the fact the pipes are lower than the radiator, and heat wants to rise...what this will do.

Regarding your other radiator, you have to make sure the valve is open , and then bleed it again with the system under enough pressure that air or water will come out, and see if you can if the piping is done in a standard trunkline type configuration, or if this particular radiator was put in series with another radiator. I have seen such applications. A trunkline type (my own terminology for your understanding) of piping network would be where the supply lines to each separate radiator all fork of of a main supply line from the boiler, and the return water from each radiator goes into another trunk line that returns to the boiler. "In series", you would have the supply line go into one radiator, which outlet pipe then would supply some other radiator, before dumping back into a trunk line.

 

Post pictures it sure helps, Whats the psi on the boiler??

 

Ok, here goes...

Side view of the top half, showing the chimney pipe. The black thermostat (at least, I think that's what that is) is set to 170F, the grey one (viewed from the side) is set to 180F
http://www.renegadenation.ca/heat/PICT1141.JPG

Side view of the bottom half - there's been a bit of water coming out of the pressure relief valve lately and I emptied the bucket this afternoon and dropped a bit on the floor...
http://www.renegadenation.ca/heat/PICT1142.JPG

The other side, showing the pump/motor. The gauge on the side has two needles and is showing
20psi (range is 0 to 75 psi) and temperature of 120F (range is 70-230F)
http://www.renegadenation.ca/heat/PICT1143.JPG

Some of the pipes coming in and out of this darn thing...
http://www.renegadenation.ca/heat/PICT1144.JPG

The expansion tank. The gauge in the picture is showing 14 (range 0 to 60, I assume PSI?)
http://www.renegadenation.ca/heat/PICT1145.JPG

Pipes going to the baseboard radiators on the other side of the furnace room. These go to one of the problematic units which don't always put out heat even tho the rest of the house is ok (except for the upstairs washroom).
http://www.renegadenation.ca/heat/PICT1147.JPG

I should mention - the boiler is a Burnham V72, mfg date is 1998... As previously stated, I bled all the radiators in the upstairs of the house (could not figure out how to bleed the baseboard basement units), and the system has not been flushed and cleaned in at least 2 years (since I've owned the house), and probably much longer than that, based on the rest of the poor maintenance I've discovered since I've purchased the property.... I'd like to know how to do that, too (where to buy the product, how to put in the system, etc...) Lastly, I'm located in Ontario, Canada - so we get some real nasty frigid weather at this time of the year.

Hope that's enough info to get going, but let me know if you need more. Any input and advice very appreciated !

Thanks a million gang !

 

Your missing the one picture I would have loved to have seen. Where that downstairs rad ties up in the main piping, could you take a picture of the tee and post it?

 

Have you confirmed that the circulation pump is moving the water in the pipes? If water even sprays out of bleeder valves, this does not mean the water is circulating, you know. That only shows you have the 20 psi. It could be static and water would still come out. Non-circulating water could explain why higher radiators are getting warm, and low ones are not, since heat will naturally rise through the piping, by itself. The 120 temp shows that the boiler is running to at least some degree and would be sufficient temp to determine heat at all radiators if no other problems. Check the pump. Some are sealed and you can't see if a shaft or impeller is spinning.

 

Ok, thanks for the info ! I'll check it out and report back.

As far as the piping to the baseboard radiators - there's nothing special there - it's just a T connection with the rest of the system, as far as I can tell...

 

GoGades, if your heating branches all just tee off the main pipe, then you have a diverter tee distribution system. This was made popular by B&G with their Monoflo fittings but others companies made them as well.

The velocity/flow on the main through\-pipe has to be high. The second tee on these systems is a special venturi tee. As the water passes through the tee it squeezes it slightly in a venturi. The branch's opening on the inside of the tee is around the outside. The velocity of the through pipe, in effect, sucks water through the branch. The water doesn't have any reasons to go down the branches that are always more restrictive. Branches going under mains have the special tee turnned around to scoop water and suck at the other end to overcome the bouyancy.

When the heat gets uneven it's a sign the the velocity isn't sufficient for all the branches. It can be caused by adding restictions in the form of partially closed valves/branches, air pockets in branches, piping changes, frozen branch sections, etc.

It can also be caused if the boiler's impeller can't generate the same flow that it once did. Circs get old, impellers get worn... If you are sure all the branches are open, not frozen and are properly bled, I'd get a new circ.

What circ/pump do you have there now?

 

I have a same problem right now. One of my radiators upstairs suddenly does not work. Hot water is not flowing through at all.
(I have one-pipe system; each radiator is attached to a main pipe)

It might be a velocity problem because just today, new pipe for convectors was attached to a main pipe. A radiator which is having a problem now is right next to it. Two attached pipes (1 is returning pipe from non-working radiator, 1 is going into a convector) are located so close, would that slow the flow?

Till yesterday, this radiator was ok. Hot water was going through.
Today, the pipe was added so close to this radiator's pipe. So this should be a problem.

Right now, I have no idea what to do to make hot water flow through this radiator... Please help!

 

Have you bled the cold rad?

 

I bled the cold radiator last night, but still hot water did not flow. I read other posts and this morning, I tried again. This time, I closed other radiators. After taking many gallons of water from radiator, it seems it's working now. I guess I did not do enough bleeding last night.

anyway, thanks. this forum is very helpful for the one like me (who don't know much about heating system and all...)

 

If there's no air, then check for pressure (system pressure and obstruction -- open all valves) and flow (maybe the pump impeller is losing its gpm rating).