Issue with oil boiler curculating water constantly


Old 01-06-16, 09:29 AM
Thread Starter
Join Date: Jun 2014
Posts: 37
Received 0 Votes on 0 Posts
Issue with oil boiler curculating water constantly

Hi guys. I have an oil boiler/hot water baseboard system. The boiler fires up and cycles normally. However the water itself is almost always cycling through the system. Even when the boiler is not firing.
I'd say about 90% of the time the water is cycling through the system. You can hear the pump, hear the water flushing through.

Not sure why this is happening.

There is a 2nd boiler for another floor that works perfectly, and does not exhibit this issue. Both boilers are exactly the same. Pressure, temp, etc....all reads normal.

Any ideas?
Sponsored Links
Old 01-06-16, 10:45 AM
Join Date: Dec 2014
Location: United States
Posts: 103
Received 0 Votes on 0 Posts
I don't have many answers, but I don't believe that it is normal to hear the water actually flowing. I would first bleed the air from the system.
Could there be an issue with your thermostat?
Old 01-06-16, 10:51 AM
Join Date: Mar 2010
Location: USA
Posts: 3,745
Received 40 Votes on 38 Posts
The circulator and the burner do not always run in synchronism in modern forced hot water boilers.

The burner should turn on and off depending on boiler water temperature.

Thr circulator usually turns on and off via the room thermostat.
Old 01-07-16, 08:26 PM
rbeck's Avatar
Join Date: Jul 2007
Posts: 2,466
Received 2 Votes on 2 Posts
Maybe the application is set up that way. In the 60's the University of Illinois tested for Hydronic Institute and one thing they tested was constant circulation among other things. The proved the comfort level was increased by constant circulation and cycling the burner as needed. There was also a fuel savings. the thermostat only demanded heat until it was satisfied and than shut down the burner. No over heating and hot & cold spots were eliminated.
For more info see the link below.
Comfort Calc

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Thread Tools
Search this Thread
Ask a Question
Question Title:
Your question will be posted in: