How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask James I Your Own Question
James I
James I,
Category: Plumbing
Satisfied Customers: 2155
Experience:  Expert at Just Answer
Type Your Plumbing Question Here...
James I is online now

New extension Can I add three additional radiators and one

Customer Question

New extensionCan I add three additional radiators and one 50m2 under floor heating to my existing system.Boiler - Potterton StatesmanCan I Tee of the hot water supply to the existing bathroom and run into my new extension, the tap in the new extension will be 40m away from the water heater. Will there be enough pressure? (I believe the water heater runs of mains pressure)Water heater - MegaFlo CL145
Submitted: 6 months ago.
Category: Plumbing
Expert:  James I replied 6 months ago.

Central Heating:

What mechanism are you using for your underfloor central heating, traditionally electric underfloor heating is more effective.

With regard to plumbing in the floor and rads, what is the additional BTU demand on the boiler?

Secondly what size pipe are you planning to T into, as you probably need to find 15mm feed rather than a 10mm tail

Hot Water:

A mega flow is a a mains pressured hot water system, so a 40m pipe run is not a problem, but depending on the use eg basin or bath, you may wish to use a 22mm feed for a bath compared to 15mm for basin.



Customer: replied 6 months ago.
the underfloor heating is a wet system is says it provides 125w per m2, there 40m2 so 5000w or 17,060 BTU (i think that is correct.The radiators upstairs are 2660, 1228, 4168 btuso in total an extra 25,116 btu ??!!proposing to use15mm pipes for radiators
22mm for bath
15mm for sink
Customer: replied 6 months ago.
the tecnical data for the potterton says its good for 79,000 btu, it currently running 6 radiators
Customer: replied 6 months ago.
with regards ***** ***** feeds for baths etc, does it matter that the the feed from the water heater steps down to 15mm behind a cupbaord then steps back up to 22mm, will this affect the pressure? or does it need to be just 22mm from the water heater?
Expert:  James I replied 6 months ago.

Central Heating:

You have already done the hard work for me and confirm your boiler can provide the additional output needed, you may however need to increase the pump speed to circuate the water and re-balance other radiators if you find them not getting hot.

Hot water:

Its not a pressure issue but rather water flow, to confirm your saying the inlet into the mega flow from cold mains is 15mm at a point, or the outlet from the mega flow is 15mm before going back to 22mm, in either case I would look to change it to 22mm if you can, but it rather depends how quickly you want to fill you bath as to if it will cause you any real inconvenience.