Central heating questions

[The Pink Panther]

Hi all, my mother has a heating system which comprises of boiler, cylinder tank, cistern in the loft (i think) and a pump.If she needs hot water she has the boiler fire up via the remote time clock for 1hr and if she needs heating she switches the time clock to constant.It is not a combi boiler.I need to move a rad for the installation of new french patio doors.I need to turn of the water supply at the main stop-cock then drain the system from the drain valve by the boiler, remove rad from wall the divert the pipework to new position.I think I can handle this so far.How would the system be re-filled?On my combi at home I have a valve on the cold water feed pipe to enable me to do this.Am I correct in thinking it will be done from the header tank in the loft after I restore the water supply.
Any help on this matter would be greatly appreciated.

Thanks guys and gals.

 

[nstreet]

You shouldn't need to turn of the mains water. In the f&e tank, there is a setup similar to that in your w/.c. just tie up the ball cock. I normally place a piece of wood across the f&e tank and loop the string around the ball cock. When draining the system, don't forget to make sure the valves to the rads are fully open and open the bleed screws one one until the system is drained.

Refilling is fairly straight forward, just untie the ball cock, the system will then fill itself. Be prepared for air locks though, they can be fairly common after a drain down. Plenty of posts on this sort of topic if you do a search.

 

[The Pink Panther]

Thanks for your reply.Forgive me but what does the f+e stand for.I will do a search now.

 

[Dick n Dom]

Feed and expansion...

 

[The Pink Panther]

Thanks for replying guys.Can I run this scenario by you.My mother has an old 8ft rad in front of window.New patio doors being fitted.Now been decided 2 smaller rads to be repositioned either side or the doors on the dwarf walls that will be there when doors fitted.When I lift the floorboards up I will have a flow and return pipe.Whats the best way to re-route the pipes to these 2 new rads.I always used to think that from the boiler came the flow to the first rad then left that by way of the return pipe to the next rad which then became the flow and so on until it went round all rads and then back to the boiler.I think that is not the case.Would I be best taking the flow to one rad and the return to the other then t off each to the other rad.I'm sorry if this post has become confusing.

 

[nstreet]

The flow and return are two different pipe runs. The flow goes into one side of each rad and the return exits from the other side of each rad (assuming that you haven't got a single pipe system). This site may help you. http://www.diyfixit.com/flash/centralheating/CHSystems/systems.htm

Its easier to see if you colour in the flow and return pipes in different colours.

 

[Nige F]

Thanks for replying guys.Can I run this scenario by you.My mother has an old 8ft rad in front of window.New patio doors being fitted.Now been decided 2 smaller rads to be repositioned either side or the doors on the dwarf walls that will be there when doors fitted.When I lift the floorboards up I will have a flow and return pipe.Whats the best way to re-route the pipes to these 2 new rads.I always used to think that from the boiler came the flow to the first rad then left that by way of the return pipe to the next rad which then became the flow and so on until it went round all rads and then back to the boiler.I think that is not the case.Would I be best taking the flow to one rad and the return to the other then t off each to the other rad.I'm sorry if this post has become confusing.

you`re thinking of the OLD one pipe system Take a flow to each rad and a return from each rad using a T in each existing pipe to make it into 2

 

[The Pink Panther]

Thanks for replying guys.The pipes that go to existing rads are about 10mm2 diameter.The flow and return leave the boiler in 22mm2.Can I just put a t on the ends of the 10mm2 or do I have to go back to the larger pipes and t there to ensure adequate pipe size and flow are met?Cheers.

 

[nstreet]

I would 't' off the existing pipes (unless its easier to take off from the 22mm). I wouldn't think the extra pipe for the two seperate rads is going to make that much difference to the flow. The 't' wont actually be on the 'end' of the pipes as the pipes will continue on under the floor to the next rads, unless the rad is the last on the leg in which case use elbows. You will need to rebalance the system after you have fitted the new rads. Again plenty of posts on the forum for this. Have fun