One radiator a long way from the zone loop

Stu M

I have a brand new 50 year old house with a one loop zone.
One radiator, on an addition to the house, has the following properties.
a. It is at the end of a long copper run (30 ft) from the zone loop to the radidiator.
b. The radiator hardly gives any heat.
c. Both the delivery pipe to - and the return pipe from the radiator - have a shutoff valve about one foot from the zone pipe connection.

1. Can anyone suggest a reason as to why the valves were put there? My presumption is that in some way, they can be manipulated to control the flow to give the radiator more heat.

2. Even more importantly, can someone suggest any way to increase the heat output from the radiator?

Many thanks in advance...

Justin Gavin

Some Thoughts

Well Something to think about. The Valves were there for a couple of reasons.

1. To regulate flow
2. To Isolate the loop if you were going to remove the radiator.

What are you using to heat the rest of the house?.

Is the whole house radiators or is it baseboard ?

What is the supply temperature of your boiler water. If you have the system set on any type of reset you may consider adjusting the boiler supply temperature to supply hotter water to that last radiator.

As far as the valves,
you should only really worry about the the pipe returning to the boiler. Is is wide open or partially closed.

If it is open slowly start to close the valve (but not all the way) and watch and wait as you close it. Mark the positions of the valve with a marker or something so that you know what feels right.

Keep slowly closing the valve a little bit at a time to see what feels right for you.

Also is there a bleeder valve on the radiator? you may have some air trapped in the radiator that wouldn't allow the radiator to give off heat. Try opening the vent (if there is one) and see if you get any air.

Last but not least and probably the last resort. If it is an addition it is possible that that the radiator was never calculated for the original boiler. This might not be a problem because back in the day they usually oversized the boiler. But you might need a different pump depending on the pressure drop created by the radiator. Remember that as the loop goes through every thing you have connected to that loop will take heat away. This includes the 30 feet of piping that goes to the radiator. What size pump do you have?

I would check you system out like this.

1. Check that there is no air in the radiator
2. Adjust the valve on the return.
3. Raise your supply temperature or adjust your reset control (if you have one)
4. Check that your pump has enough UMPF

5. If you still get confused check out the "find a professional" part of this web site.

Good Luck.

Kent_3

It sounds like you have a loop connected to a loop and you are thus short-circuiting the new radiator. Put a shut-off valve between the two tee connections for the new radiator loop. Shut this valve and make sure the other ones you talked about are fully open. You should notice a marked improvement at the new radiator. After testing, you may also want to open the new valve slightly to give the downstream radiators more heat.