Adding a Rad

[capri579]

Hi all.
I would welcome advise on adding another raditor to my existing c/h system. Worcester Bosch comb boiler fitted 2 yrs ago. Rad's are approx. 15yrs +. Currently we have 2 rads in series in the front room. Kitchen/dinner is adjasent but no rad hence it gets v cold in winter.
Am i ok to fit rad(1.2m double fin approx 8000BTU) in the dinner area with feed from nearest rad in front room. So i would end up with all 3 rad in series.
What is t process of switching off the boiler. do i drain all the system or do i shut off all the valves(3 rads upstaires). and what is the procedure for filling the sysyem ofter adding new rad.
Your help is very much appreciated

 

[sooey]

Assuming your downstairs rads are fed from above, what size are the pipes feeding them? If they are 15 mm you should be able to add a rad, if 10 mm then you'd be best bringing another drop down from above.
They shouldn't be piped 'in series' though.

 

[capri579]

Assuming your downstairs rads are fed from above, what size are the pipes feeding them? If they are 15 mm you should be able to add a rad, if 10 mm then you'd be best bringing another drop down from above.
They shouldn't be piped 'in series' though.

Thanks for you advise. pipe size is 15mm. Will try and describe pluming of current 2 rads.
2 Rads are on the same wall. 2 pipes come down in one corner of room. One pipe goes to left side of 1st rad. Pipe from right goes to left side of 2nd Rad. Pipe from right on 2nd rad, goes along the bottom of both rads and returns to corner and back up the wall.
Will it be on for me to take the return pipe to the new rad and fit to the furtherest value and return the pipe back to the corner and connect to pipe going back up to the ceiling.

 

[Whitespirit66]

15mm pipe can supply 15,000BTUs. If all of the three rads equal more than this, you will need a new drop from the main feed and return pipes for the new rad from above.

 

[Whitespirit66]

2 Rads are on the same wall. 2 pipes come down in one corner of room. One pipe goes to left side of 1st rad. Pipe from right goes to left side of 2nd Rad. Pipe from right on 2nd rad, goes along the bottom of both rads and returns to corner and back up the wall.

Do you find that the second rad runs cooler? If the rads are largeish/doubles, the answer is probably yes. Ideally should be piped in parallel, not series.

Will it be on for me to take the return pipe to the new rad and fit to the furtherest value and return the pipe back to the corner and connect to pipe going back up to the ceiling.

No, they need to be piped in parallel. Something like the image below. (ignore the 'joints to existing capped pipes' bit - this diagram was for another similar installation.) Piping the 3 rads like this is OK if they don't total 15,000 BTUs or more. As said, will need a second dedicated drop of pipes teed into main F and R pipes above, if total exceeded.

View media item 18393

 

[capri579]

2 Rads are on the same wall. 2 pipes come down in one corner of room. One pipe goes to left side of 1st rad. Pipe from right goes to left side of 2nd Rad. Pipe from right on 2nd rad, goes along the bottom of both rads and returns to corner and back up the wall.

Do you find that the second rad runs cooler? If the rads are largeish/doubles, the answer is probably yes. Ideally should be piped in parallel, not series.

Will it be on for me to take the return pipe to the new rad and fit to the furtherest value and return the pipe back to the corner and connect to pipe going back up to the ceiling.

No, they need to be piped in parallel. Something like the image below. (ignore the 'joints to existing capped pipes' bit - this diagram was for another similar installation.) Piping the 3 rads like this is OK if they don't total 15,000 BTUs or more. As said, will need a second dedicated drop of pipes teed into main F and R pipes above, if total exceeded.

Hi thanks for your invaluable advice. I will add new rad & replumb the old rad's you are correct one rad is colder then other.
Can you please advise on draining the comb boiler system and filling up after.
All the work i have done to date, on s/h systems has been on boilers with expansion tanks. This is my first task with a pressurized system
View media item 18393

 

[capri579]

Hi thanks for your invaluable advice. I will add new rad & replumb the old rad's you are correct one rad is colder then other.
Can you please advise on draining the comb boiler system and filling up after.
All the work i have done to date, on s/h systems has been on boilers with expansion tanks. This is my first task with a pressurized system


Read more: //www.diynot.com/forums/plumbing/adding-a-rad.349523/#2622989#ixzz2GZ0DYdd2[QUOTE="capri579, post: 2622989"]

2 Rads are on the same wall. 2 pipes come down in one corner of room. One pipe goes to left side of 1st rad. Pipe from right goes to left side of 2nd Rad. Pipe from right on 2nd rad, goes along the bottom of both rads and returns to corner and back up the wall.

Do you find that the second rad runs cooler? If the rads are largeish/doubles, the answer is probably yes. Ideally should be piped in parallel, not series.

Will it be on for me to take the return pipe to the new rad and fit to the furtherest value and return the pipe back to the corner and connect to pipe going back up to the ceiling.

No, they need to be piped in parallel. Something like the image below. (ignore the 'joints to existing capped pipes' bit - this diagram was for another similar installation.) Piping the 3 rads like this is OK if they don't total 15,000 BTUs or more. As said, will need a second dedicated drop of pipes teed into main F and R pipes above, if total exceeded.

Hi thanks for your invaluable advice. I will add new rad & replumb the old rad's you are correct one rad is colder then other.
Can you please advise on draining the comb boiler system and filling up after.
All the work i have done to date, on s/h systems has been on boilers with expansion tanks. This is my first task with a pressurized system
View media item 18393

[/QUOTE]

 

[Whitespirit66]

You will need to drain the two rads, the pipework that goes from them to above, and anything upstairs, eg. pipes, rads and the boiler if it's upstairs. Don't worry about draining drops to other downstairs rads.

Is there a drain off cock on the drop to the two rads? Sometimes there is one on the rad valves or the pipework below the rads. Instead, there may be one or more under other downstairs rads and/or under the boiler if it's downstairs.

Untitled

• Whitespirit66
• 29 Aug 2011
• 7

 

[Jamesie]

Concuring with whitespirit, i have fitted drain offs to all my down stairs rads for ease, when draining may be required, when filling if you have the luxury of another person, ensure all bleed valves are shut, and rad valves open, fill to 1.5bar and start bleeding upstairs, whilst doing so get your helper to maintain the pressure to 1.5bar

 

[capri579]

Thanks for your clear advise
Happy & prosperous New Year to you and your family

You will need to drain the two rads, the pipework that goes from them to above, and anything upstairs, eg. pipes, rads and the boiler if it's upstairs. Don't worry about draining drops to other downstairs rads.

Is there a drain off cock on the drop to the two rads? Sometimes there is one on the rad valves or the pipework below the rads. Instead, there may be one or more under other downstairs rads and/or under the boiler if it's downstairs.

Untitled

• Whitespirit66
• 29 Aug 2011
• 7

 

[capri579]

Thanks for your clear advise. (tip most valuable)
Happy & prosperous New Year to you and your family


Read more: //www.diynot.com/forums/plumbing/adding-a-rad.349523/#2623178#ixzz2GZlFaE2U

Concuring with whitespirit, i have fitted drain offs to all my down stairs rads for ease, when draining may be required, when filling if you have the luxury of another person, ensure all bleed valves are shut, and rad valves open, fill to 1.5bar and start bleeding upstairs, whilst doing so get your helper to maintain the pressure to 1.5bar