No heat in one zone


  #1  
Old 09-13-06, 09:33 AM
B
Member
Thread Starter
Join Date: Nov 2004
Location: NE Massachusetts
Posts: 202
Received 0 Upvotes on 0 Posts
No heat in one zone

I have a 3 zone oil-fired hot water baseboard heating system. This morning I turned up the thermostat for the upstairs zone and nothing happened. The two downstairs zones worked OK a few weeks ago. I'm suspecting that I have a bad zone valve. I'm planning to have my wife operate the thermostats for one of the downstairs zones as well as the upstairs zone while I watch to see what happens. Can zone valves just stick closed due to no activity during the summer? Is it possible to free them up with a lubricant or forced mechanical operation? Since I haven't had any problems with the zone valves yet I don't know what type I have. The heating system is 16 years old.
 
  #2  
Old 09-13-06, 06:01 PM
Grady's Avatar
Forum Topic Moderator
Join Date: Jan 2005
Location: Delaware, The First State
Posts: 12,682
Received 41 Upvotes on 39 Posts
Zone valves

Yes they can stick due to inactivity & once in a great while you can free them by operating manually. This is particularly true of Honeywell or other electro-mechanical valves. I have never been sucessful in freeing up a stuck Taco or other heat motor type.
 
  #3  
Old 09-21-06, 08:30 PM
B
Member
Thread Starter
Join Date: Nov 2004
Location: NE Massachusetts
Posts: 202
Received 0 Upvotes on 0 Posts
Zone Valve Follow Up

I had my wife turn up the thermostat for the zone that doesn't work as well as for one that does. In both the cases the Honeywell motorized zone valves do the same thing--the clock motor turns the gear segment down to the point that it hits a microswitch that starts the circulator motor. When the thermostats are turned down the zone valves go back to their initial position. I checked to make sure the manual valve next to the zone valves was open and both were. But I still get no heat. The zone without heat is on the second floor. Both first floor zones work fine. I recently had the relief valve and pressure tank replaced. Could that have something to do with why I'm not getting heat on the second floor? Why do I have no heat when the zone valve mechanism operates and the circulator motor runs? Can the valve mechanism itself stick and still allow the actuator motor to operate? It looks like the motor mechanism can be removed from the valve with just a few screws. Should I do that and manually operate the valve mechanism?
 
  #4  
Old 09-21-06, 08:36 PM
Grady's Avatar
Forum Topic Moderator
Join Date: Jan 2005
Location: Delaware, The First State
Posts: 12,682
Received 41 Upvotes on 39 Posts
Zone valve

Since the zone valve is operating the end switch, I doubt the valve is the problem. You could have air in that zone or if the pressure on the boiler is not 12-15# you might not have enough pressure. If you can take some pictures of the near boiler piping, post them on photobucket or other photo hosting web site, & provide a link here, it would make it a lot easier to explain how to purge the air.
 
  #5  
Old 09-22-06, 04:52 AM
B
Member
Thread Starter
Join Date: Nov 2004
Location: NE Massachusetts
Posts: 202
Received 0 Upvotes on 0 Posts
Air in System

I just checked the boiler pressure gauge--it's showing 15 pounds. I would expect that since the pressure tank was recently replaced. I was wondering if I might have a trapped air problem since only the highest zone has a problem. So if you're suspecting air in the system I think I'll call the guy that replaced the relief valve and pressure tank. He may not have properly bled the system. Thanks for the offer of posting photos. I'll decline that for now.
 
  #6  
Old 09-22-06, 03:08 PM
sdanville's Avatar
Member
Join Date: Jan 2003
Location: Western Michigan
Posts: 80
Received 0 Upvotes on 0 Posts
Feel the pipe

it is so easy to see if water is making it thru a particular valve..feel the pipe on the out go part of the non working valve.. and feel the pipes in the rooms not warming..if they are a little warm then the valve should be open a little.
AND OR swap motors and see what happens. and 3) maybe to this first...tap it with a ball peen about 20 times.
I cant tell you how many hundreds of times I have hit all the parts on my old honeywell,. the tank, the control box, the gas valves, the control valves....they all have needed coaxing over the years.
 
  #7  
Old 10-01-06, 09:12 AM
B
Member
Thread Starter
Join Date: Nov 2004
Location: NE Massachusetts
Posts: 202
Received 0 Upvotes on 0 Posts
Smile Bleeding fixed the problem

The second floor zone was indeed air bound. After bleeding that zone things are back to normal.
 
  #8  
Old 10-01-06, 09:29 AM
Grady's Avatar
Forum Topic Moderator
Join Date: Jan 2005
Location: Delaware, The First State
Posts: 12,682
Received 41 Upvotes on 39 Posts
Air Bound

Glad you got it fixed. It is amazing how a small pocket of air can keep that water from flowing.
 
 

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