100 year Old house radiant sysytem/remodel issue

dswilly

<span style="font-size:12pt">Greetings,</span>

<span style="font-size:12pt">We have a house built in 1914 with a radiant heat system.  The radiators and piping are mostly original. I put new valves on all) but the boiler is from the mid 90’s which is a Hydro-Therm.  Here is the situation, the house has three stories and has radiators on the third floor and a 2</span><span>nd</span><span style="font-size:12pt"> floor sun room with a radiator. I have since started a remodel of the second floor sun room and run new copper from the existing steel pipe into this room in a loop with a bleed valve to release air.  When the system is re- flooded I can’t get the loop in the sun room to get hot or even warm.  It tees off a line from another second floor bathroom with a radiator that gets plenty hot, even when I turn off this radiator the sun room line stays cold, only warm for the first two feet.  I also can’t get the radiators on the third floor to heat up.  I have bled all the radiators in the sun room and third floor,  all have water but not warm water.  Any thoughts?  The other rooms get nice and toasty.  Any help appreciated.</span>

Gordy

Cold rads

Did the radiators function properly before you did the repiping?



What is the pressure gauge at the boiler reading?





How long did you purge each rad when you refilled the system after work was done?

dswilly

Cold rads

Thanks for the reply

Did the radiators function properly before you did the repiping?

I don't recall if the radiators on the third floor or in the sun room worked before. I do remember one of the ones on 3 being warm. They had old stuck valves, of which one broke off.



What is the pressure gauge at the boiler reading? About 16-18PSI





How long did you purge each rad when you refilled the system after work was done? I let the valve open until water came out then shut them.

Gordy

Rewind

So you recently acquired this home, and renovating?



The original setup was a gravity system, meaning there was not a circulator to move the water in the piping. The water moved by gravity through the differences in density of the hot water produced at the boiler, and the cooler water returning from above.



At some time the system was converted from gravity, and a circulator was added. If you have large diameter piping this is a give away of an old gravity system.





Since you do not know if the rads in question ever really worked its hard to say if your new piping is part of the problem. Usually if something worked before, and there was a change, and now it does not work then the change would be suspect.



Your pressure should be fine. Could need more bleeding done correctly. Could be a circulator also. Bleeding should be done with the circ off, and start at the rad farthest from the boiler, and work your way to the boiler. Making sure you maintain pressure while bleeding.



If after properly bleeding you still are not getting heat then it is probably a balance problem in the piping. Some pictures of the system would be very helpful.

dswilly

Gravity hmmm

Gordy,



Thanks for the reply. We have owned the home for about 6 years. The renovations have been on going. I didn't think about the gravity system, yes there are larger pipes, maybe 3-5" diameter in the basement that smaller ones tee off of. I thought about the circulator being bad/ weak. I think I bled the pipes with the circulator off as it only runs when the boiler kicks on correct? And I bled the system cold. How would one test a circulator? Does putting on a bigger pump help?

dswilly

Circulator question

When the circulator is running does it make any noise at all? Mine which

Is a red grundfos doesn't seem to make nary a sound, not even a faint hum. If it doesn't work would the system work like a gravity system by default?

Gordy

Air vents

Is there air vents at each radiator?



It does not take a very big circ with gravity piping there is very little head.



Could you produce some pics of the boiler room, and piping?



Is there flow checks installed? These would be in the main supply piping to prevent gravity flow when the circ is off. If there is not one then it would be possible that the circ could be off, and hot water would still flow in the piping, but you would have hot radiators that are working most of the time until the boiler cooled.

Gordy

Quiet circulator

Take a long screw driver put it on the piping by the circ then the handle to your ear you should hear water flowing in the piping, or the impeller moving water.

dswilly

Air vents & photos

Yes to vents at all radiators, new valves too. Attached are some photos. Thanks for the help

dswilly

Flow checks

I didn't see anything that looked like a flow check, only shut off valves everywhere.