How many radiators can be used on a system - any hard and fast rules?

[Marty32]

Afternoon folks

Could anybody tell me if there are any rules arounded adding radiators to a system and whether there is any reading material out there to find out how to size a system?

Does it depend on the boiler size etc

Grateful for any tips and advice

Mart

 

[Best]

Boiler output, pipe sizes from boiler and to radiators are all important. Also, sometimes circulating pump has to be proper for size of system & pipes.
If it is just adding a few rads, then it may be fine to join to the larger main runs of pipes. 15mm pipes really should only do 1 large rad or up to 4 small rads max approx.
Really better to get an engineer in to recommend what, if any modifications are needed to system.

 

[jtsplumbing]

Boiler size / Pipe size / Pump size Loads of books etc on heating design have a look on ebay !

 

[chris watkins]

Can recommend the "Domestic Heating Design Guide" every thing you wanted to know about heat systems but were afraid to ask!!
ISBN 1 903287 40 5 (2007)

 

[Simon F]

Plenty of bedtime reading, you could try this one

http://www.planningportal.gov.uk/uploads/br/BR_PDF_PTL_DOMHEAT.pdf

 

[doitmyself]

Plenty of bedtime reading, you could try this one

http://www.planningportal.gov.uk/uploads/br/BR_PDF_PTL_DOMHEAT.pdf

That's now out of date, the current version is Domestic Buildings Compliance Guide 2010.

In any case. the Guide does not tell you how to design a system, only what has to be done to ensure it meets current Building Regulations.

 

[doitmyself]

Could anybody tell me if there are any rules around adding radiators to a system

Does it depend on the boiler size etc

If you are just adding rads to a system you need to know two things:

1. The output of the boiler (in the boiler manual or on manufacturer's web-site);
2. The total output of the existing rads (manufacturer's catalogue or Stelrad Elite Catalogue if mfr's info not available)

The important thing is that the rad total must not exceed the boiler central heating output (often lower than the hot water output on a combi boiler).

If you are designing a system from scratch you need to calculate the heat loss for each room and select the appropriate radiator. The rad total then tells you the required central heating output for the boiler.

 

[chris watkins]

Don't forget that there is a maximum amount of heat (hot water) that each size of pipe can carry, therefore need to total up the amount of rad outputs (both installed & proposed) for each section they should not exceed the following. 15mm pipe 6000 Watts, 22mm pipe 13000 Watts this is only rule of thumb & I normally use a lot less (3500 & 12000)

 

[fuzzy]

just like a car, bgger car needs bigger engine

 

[diamondgas]

Afternoon folks

Could anybody tell me if there are any rules arounded adding radiators to a system and whether there is any reading material out there to find out how to size a system?

Does it depend on the boiler size etc

Grateful for any tips and advice

Mart

Mart you tickle me I thought you were at college learning all this stuff?

 

[Bernie2]

Hmm!

Interesting, have you considered the problem of distance and heat loss? In bigger buildings you may require higher water temperatures or even steam heat. Simply because the water gets cold before it reaches the furthest rad.

 

[chris watkins]

Hi Bernie2 you clearly work on much bigger buildings than most of us if you need steam, do they do a condensing steam raising boiler ?? LOL
O & Mart if you need a refresher in heating design let me know, as you are close, can sort a short course out to suit your needs.