unvented hot water relief pipes

[dpgservices]

hi guys im a self employed 22 year old and need a bit of a nudge in the right direction, i have just started a job fitting new system boiler and unvented cylinder ive done roughly 5 or 6 of these and know them fairly well BUT the reilef pipes get me some times.

are you allowed to put both reilef pipes into the same tundish?

and if you have a cylinder up stairs what would the best way to run the reilef pipe ( no roofs just plain gable end ) stright out and down 100mm above floor with cage? in 28mm as its roughly 7m with 2 elbows?

thanks for any advice lee

 

[newbuildinstaller]

Id use 1.25" push fit waste outside the same colour as any drain pipes present. Mainly as 28mm copper wouldnt last long round my way and costs a lot more

And yes you can combine the discharges as long as your D2 is big enough

YOU DO HAVE A G3 QUALIFICATION THOUGH DONT YOU? as unvented is very dangerous!!!

 

[dpgservices]

yes i have my unvented hot water qual haha, i was going to run the 28 interaly down the chimney breast and then out so its less on the eyes out side, its the same round out way for the copper though. i would prefer to use waste pipe but regs state it has to be able to withstand temps of 110 and that stuff is dear!!!! thanks for your reply

 

[dpgservices]

i tell you why it throws me with the relief pipes i had one about a month back, the 3 bar relief off the cylinder was 15mm and the 8 bar relief was 22mm but the tundish was 15mm too 22mm what do you do in this situation?

can you run both seperate?

must both relief pipes have a tundish?