" can i add on a flow+return system onto my existing sy

[adrian_ninja]

PLEASE HELP. MY EXISTING CH SYSTEM IS A SINGLE PIPE SYSTEM WHERE A SINGLE 22mm PIPE FROM THE FLOW OF THE BOILER GOES ALL ROUND THE HOUSE AND BACK TO THE BOILER RETURN. AND ALL THE RADS ARE " TEED" OFF THE SINGLE PIPE. THE SYSTEM WORKS EXTREMELY WELL AND ALL THE RADS GET RED HOT. WHAT I WANT TO DO IS INSTALL A NEW BOILER IN A RECENTLY BUILT EXTENSION AND CHANGE TO A Y-PLAN ( BECAUSE THE EXISTING SYSTEM ISNT Y-PLAN, I HAS A SEPERATE GRAVITY FLOW/RETURN TO THE HOT WATER CYLINDER ) AND I RECKON THAT AFTER THE DIVERTER VALVE, I CAN TEE TOGETHER THE EXISTING FLOW AND THE NEW FLOW OF THYE EXTENSION PIPEWORK. I RECKON IT WILL WORK - SO DO HONEYWELL AND SO DOES THYE BOILER MANUFACTURER, BUT THEY SASID THERE MAY BE SOME CLEVER BALANCING ASFTERWARDS... PLEASE HAS ANYONE ANY THOUGHTS - IT WILL BE TEMPORARY AS I WILL SORT THE SINGLE PIPE SYSTEM OUT AT A LATER DATE ..... THANKYOU..
- ADRIAN

 

[oilman]

I know that lots of people have Y plan systems, but what is also on the honeywell (I think) site is the information that people have found the Y plan a problem, and have changed to an S plan. This means an extra valve, but they do last a long time, and you get positive control over the HW and CH.

With the S plan you could eep your single pipe system and save a lot of disruption which will have a questionable advantage. Have you thought of keeping your single pipe, and do you see a two pipe system will have any advantage?

 

[adrian_ninja]

dear oilman, can i thankyou for replying.. i looked at the "s"plan pipework on the honeywell site but didnt look into it in great detail,- it turns out that i have already plumbed all the pipework in the extension as " flow and return " taking the 22mm feeds into the airing cupboard in readiness for the upgrade, and obviously reducing down to 15mm at the rads, of which there are only four in total ( 2 x 6000 btu ) and 2 x 3500 btu approx. i hadnt considered the extension of my single pipe system...? - I am hoping ( praying more like ) that the teeing of the existing 22mm single flow, and the new 22mm flow for the extension will work ( basically, I'm hoping that the pump will force water in both directions after the y-valve, but i also understand that the water will take the easiest route. and of course the two resulting returns will be teed together to get back to the boiler along with the cold return from the hot water tank..
The more i think about it the more i think it will work,

thanks again for your time in coresponding to my question

 

[oilman]

Could you increase the pipe from the boiler to the Tees to 28mm? This would remove one potential problem.

You could treat the new pipewor as a seperate zone, and instead of using a diverter valve, use anither pump. Pumps are cheaper than valves and are more reliable if your system is kept clean.