Radiator flow and return

[cjonesguitar]

Hi I found this forum and wanted to ask a few question in regards to my central heating.

I have recently had central heating fitted in a first floor two bedroom flat. There are 6 radiators with plastic pipe work running through the roof space and coming down in copper with three drops (two rads on each drop).

I noticed that on each drop the second radiator on seemed to be on the flow and return the opposite way around the first radiator.

I’ve Goggled a few things so excuse if some of the terminology is incorrect:

Flow --------Rad 1 Lockshield valve--------Rad 2 Thermostatic valve---
Return-----Rad 1 Thermostatic valve-------Rad 2 Lockshield valve---

Rather than:

Flow --------Rad 1 Lockshield valve---------Rad 2 Lockshield valve---
Return-----Rad 1 Thermastatic valve------Rad 2 Thermastatic valve---

Is this OK?

The plumber I used in the end seems good and seems to have done a good job of everything else it’s just I noticed this and thought it may just be another way of doing it.

 

[Bernie2]

Could be, some thermostatic valves work on either the flow or the return. The usual way is to fit them all on the flow.

But a lot depends on where the trv is. Its best to put it on an open side i.e with a lot of air space around it, not in a corner by the wall. Its because, its the head that senses the temperature changes. If the valve is in a corner where little air circulates it can I suppose get hot very quickly and shut the valve down before the room is warm.

The thing is, piping the rad up can look unsightly if you cross the pipes over to get the trv's all on the same side. So having an alternative side to fix the trv on can make it look neater.

 

[expat]

After doing my own extensive research plastic pipe should not be in the loft as rats and mice love to nibble on it,me i have it the other way round copper in the loft and plastic pipe in the house

 

[waterbuoy]

as long as the trvs used have bi directional flow there should be no probbs and barrier pipe can be used in a loft space just make sure its lagged

 

[cjonesguitar]

Thanks for your answers. How can you tell if the thermostatic valves are bi directional? I’m sort of assuming they must be. Also I have looked and they are on the site that is open to the bigger space.

Also if some of the reds shut off I have heard that there needs to be some sort of by-pass valve? Is this already built-in the combi boiler?

 

[stevetheplumber]

Thanks for your answers. How can you tell if the thermostatic valves are bi directional? I’m sort of assuming they must be. Also I have looked and they are on the site that is open to the bigger space.

Also if some of the reds shut off I have heard that there needs to be some sort of by-pass valve? Is this already built-in the combi boiler?

if the valves were not bidirectionall you would have heard by now as when fitted wrong the make a hell of a noise some boilers do have full system bypasses installed vaillant definatly do