Uneven Heating

JMcG

We have a 1947 Cape Cod house with single pipe steam heat (gas furnance).  The system was cleaned last year and all the valves were replaced.  Unfortunately, the house heats very unevenly with the upstairs much colder that the downstairs, up to a 5-7 degree difference.  The den, on the west side of the house is the hottest room, while the bedroom directly above it is the coldest.  In fact, in order to make the bedroom comfortable, we end up sweating in the den.  We have a programmable thermostat, located in the downstairs hallway, but we keep it at a constant temperature of 72, yet the upstairs registers anywhere between 65-67 degrees.  We've had to move a portable heater into the bedroom to maintain the temperature as it is our baby's room, but we are not happy with this solution.  Any suggestions??

jpf321

balancing steam systems....

There is a strong likelihood that your system just needs some good balancing .. I would recommend 2 things to get you started on your way...both available from this site... the EDR book will allow you to measure the size of your radiators .. the balancing steam book will allow you to understand how best to utilize the sizing information. You will also need to measure the Diameter & Length of your steam main(s) and riser(s). Once you have everything in hand and are familiar with the concepts, you can use my venting recommendation worksheet (link in signature) to assist in the calculations.



Also .. read this through as well .. http://www.heatinghelp.com/files/articles/1315/123.pdf



E.D.R Book





Balancing Steam Systems Book (download)

JMcG

Thanks

Thanks for the advice.  A little discouraging since the system was supposedly balanced when they came to service it. 

jpf321

please define "they"

please explain who "they" were? if they were a burner company their job is to make sure your fire is correct, not your distribution system. only a steam specialist would be a good choice to look at the distribution side of things. 

JMcG

"They" defined

"They" are a heating and plumbing professionial specializing in steam heat we found on this site.  I trust that they did a good job and don't want to disparage them, maybe something has changed with the system and it may be time to call them back as we were very happy with their service.

Unknown

Balancing

Did your system operate  properly after the service guys worked on it?

If so, then something has changed and you need to have them out again.

Balancing a system sometimes is not that easy to do especially if there is some oddities in the system's configuration. A good pro can usually guess fairly closely but when it comes right down to it it is more of a trial / error situation to get the system to optimal performance and this has to be done over time.

I think the first thing I would do, if you haven't already done it, is to survey your system.

Make a drawing of your steam piping with the pipe sizing and length measurements . This will give you a better understanding of your system and how the components interrelate.



I would next do some timing of how long it takes steam to get to the different components.

From a cold start how long does it take to make steam. Time from when the burner starts to when you can feel heat in the risers up near the mains. Time how long it takes steam to get to the main vents. then time how long it takes steam to get to each radiator. On the radiator you can feel the heat on the inlet pipe when the steam reaches it.  The whole idea of timing is that you will then be able to see whether a change you make is beneficial or not by just re timing.



Make sure your main vents are operating properly first and then deal with the radiators. What make/model radiator vents do you have now? In you situation you want to basically  slow down your venting downstairs and increase you venting upstairs. What is happening now is the downstairs is heating up quicker than the upstairs and satisfying the thermostat before the upstairs has a chance to fully heat  up. If we slow the venting downstairs this should allow the upstairs time to "catch up" before the thermostat shuts off.

For the over heating den you might want to get a TRV for that radiator. Info on TRVs was discussed in this thread

 http://www.heatinghelp.com/forum-thread/129098/homeowner-questions-re-steam

I would also get the "Balancing Steam Systems" book (downloadable from the "Shop" at the top of this page) mentioned in a post on this thread.

I constantly refer to this book as it is full of info on venting and balancing.

- Rod