Radiator feed order from boiler

[garrymum]

Hi

Need to balance my system. Is there any easier way of finding out the feed order of the rads from boiler. Been running around like a blue @r$e fly trying to determine the order. Our house 13 radiators, 6 downstairs, 7 upstairs. Currently all LSV are fully open If I let the system heat up and measure the temp of the feed pipes, will I be able to determine the order from this, i.e. Hottest 1st, coldest last?

 

[Bahco]

Read post 8 FAQS.

You should ideally start with all the rads only open a quarter of a turn and leave to heat up for 20 mins. See which other rads need opening up a bit more.

 

[garrymum]

Thanks, yes I have booked marked that site. problem I have is finding the "running order". Runing up and down the stairs check 13 rads trying to work out which order they are fed is not easier, hence my question.

 

[wiggikins]

Is system pressurised or open vented?

 

[Bahco]

The running order?

 

[garrymum]

Open vented system.

"Running order" - you know what I mean

 

[Bahco]

You should ideally start with all the rads only open a quarter of a turn and leave to heat up for 20 mins. See which other rads need opening up a bit more.

Try it this way and stop faffing around worrying about the running order!

Some valves will only need to be open slightly and others more

 

[garrymum]

Thanks Bahco.

I closed all LSV then opened a quarter turn on all rads. Turned to room stat up to full and below are the temps of the rads.

Temperature is in degrees C

Kitchen 45 (L) 44 (R)
Dining Room 40 (L) 54 (R)
Lounge 58 (L) 38 (R)
Hall 53 (L) 57 (R)
Study 38 (L) 55 (R)
Cloakroom 54 (L) 57 (R)
Landing 49 (L) 57 (R)
Bedroom 1 - 51 (L) 46 (R)
Bedroom 2 - 42 (L) 52 (R)
Bedroom 3 - 58 (L) 50 (R)
Bedroom 4 - 58 (L) 51 (R)
Bathroom 55 (l) 53 (R)

(L) and (R) just refer to the left / right side of the rad whilst looking at it.

Ensuite rad is off whilst decorating so cannot take temp of the that one.

How on earth do I get these to all have about an 11 degree drop between feed and return. Talk about suck it and see!!!

 

[Bahco]

Are they all hot and reaching temperature reasonably quickly

 

[garrymum]

Are they all hot and reaching temperature reasonably quickly

Yes, as you can see from the temps above some have a greater loss between feed and return than others. Ideally, don't I need an 11 degree difference on all rads?

 

[D_Hailsham]

I have rearranged your data by floor and by flow temperature. The higher the flow temperature, the nearer it will be to the boiler/pump.

The rule is: close the lockshield to increase the drop; open the lockshield to reduce the drop. You do not have to make large changes. Even an eighth of a turn can have a significant effect.

If you have TRVs on any radiators, remove the head or set them to max. It is important that the TRVs do not operate while you are balancing.

I have suggested below what to do to start with. Do them in the order shown.

Flow Side
Return Side

Lounge 58 (L) 38 (R) - Drop20 - Open quarter turn
Hall 53 (L) 57 (R) - Drop 4 - Close eighth turn
Study 38 (L) 55 (R) - Drop 17 - Open quarter turn
Cloakroom 54 (L) 57 (R) - Drop 3 - Close eighth turn
Kitchen 45 (L) 44 (R) - Drop 1 - Close eighth turn
Dining Room 40 (L)54 (R) - Drop 14 - Open quarter turn

Bedroom 3 - 58 (L)50 (R) - Drop 8 - Close eighth turn
Bedroom 4 - 58 (L)51 (R) - Drop 7 - Close eighth turn
Landing 49 (L)57 (R) - Drop 8 - Close eighth turn
Bathroom 55 (l)53 (R) - Drop 2 - Close eighth turn
Bedroom 1 - 51 (L)46 (R) - Drop 5 - Close eighth turn
Bedroom 2 - 42 (L)52 (R) - Drop 10 Do not adjust the first time round

Leave the system to settle down for about 20 minutes, then recheck and readjust the lockshields until you are happy with the result.

In this warm weather you may not be able to obtain a drop of 11 degrees - it will probably be smaller. The important thing is that the drop is about the same on all radiators.

Do not strive for perfection; you will never achieve it

 

[garrymum]

D_Hailsham, thank you very much indeed.

 

[D_Hailsham]

D_Hailsham, thank you very much indeed.

Your welcome
One thing I forgot to mention

As you obviously have a thermometer or two (digital?), measure the flow and return temperatures at the boiler. This will give you a clue as to the temperatures you should see each end of the radiator and the drop you should expect to achieve.

Incidentally you have not mentioned which boiler you have. Older ones are designed to work best with a drop of 11 degrees; but modern condensing boilers work better if the drop is higher - up to 20 degrees.

PS Why is Garry not doing all this and asking the questions?

 

[garrymum]

D_Hailsham, thank you very much indeed.

Your welcome
Incidentally you have not mentioned which boiler you have. Older ones are designed to work best with a drop of 11 degrees; but modern condensing boilers work better if the drop is higher - up to 20 degrees.

Boiler is a Potterton Suprima 50

 

[D_Hailsham]

Boiler is a Potterton Suprima 50

In that case the boiler is designed for a temperature difference of 11°C.

The maximum flow temperature you give is only 58°C. What do you have the temperature control set to on the boiler? (Min=55°C, Max=82°C)? Do you have it turned down so the water from the Hot taps is not too hot?.

Balancing a system in the summer is always difficult as the radiators are not having to do much work. Systems are designed for an outside temperature of -1°C and a room temperature of 20°C. If the outside temperature is higher, say 13°C, a radiator will only need to give out one third of its quoted heat, so the radiator temperatures will be lower and the differential will not be 11°C.