Balancing rads help.....

[marshian]

11 minutes ago, Dee said:

The second image are the style I have.

I'll look into those valves...thanks for a great peice of info and advice!

Not a problem - you shouldn’t need diverters for those rads (OK they are column rads by name but not in the modern sense)

 

Just for giggles this was the view into the bottom tube of the column rad in my bathroom  (first picture)

 

So poor manufacturing tolerances meant opportunity for water to go straight thro from flow in to return out rather than be forced up the columns 

[Dee]

Marshian.....so which of the 3 valves you mentioned would you use now?

[marshian]

4 hours ago, Dee said:

Marshian.....so which of the 3 valves you mentioned would you use now?

@Dee Use the @ before a users name to tag someone (they get a notification they’ve been mentioned) and you should get a drop down to pick from

 

If I was doing it again I would use the flow setting (auto balancing type) by either Drayton (I use Wiser TRV’s but they work also with conventional Drayton TRV’s)

good explanation here

 

 

or the Danfoss equivalent

 

Either may accept your existing TRV Heads with adaptors (not sure if they are compatible or not)

 

good explanation of the Danfoss valves here

 

 

Fundamentally they both do the same thing - allow you to set up specific flow rates to individual rads that are not affected by system pressure changes (like when TRV heads start intervening in the circuit)

Both types work with the lockshield valve wide open

[MrPotts]

I think you mean valves that are affected by system pressure changes.

[marshian]

4 hours ago, MrPotts said:

I think you mean valves that are affected by system pressure changes.

 

No I don't

[MrPotts]

Isn’t the idea of an auto balancing valve to be setup initially based on the required flow rate and when this changes, due to other TRV’s closing, it automatically adjusts to try and maintain the flow rate.

[Nickfromwales]

So……they’re not actually auto-balancing then as they each require full mechanical (human) commissioning? I’m failing to see the benefit, sorry, and think it is much easier (for a newbie in particular) to get to the best result with balancing via the existing lock shield valve.

The latter is also the obvious choice in an existing install where you have the TRV’s (regular, serviceable ones) and do not want to make any changes.

 

@Dee, best to save your pennies and do this in one hit in the summer, as suggested above. Then you can take your time.

[marshian]

1 minute ago, Nickfromwales said:

So……they’re not actually auto-balancing then as they each require full mechanical (human) commissioning? I’m failing to see the benefit, sorry, and think it is much easier (for a newbie in particular) to get to the best result with balancing via the existing lock shield valve.

 

Less effort than setting up a radiator circuit from scratch - Main difference is that each one can be set up with the correct flow rate before fitting

 

Setting up with a lock shield depends on how good (or how much valve authority) your lock shields are (or have)

 

 

Precis - Some lock shields are utter garbage very few are excellent - I looked at buying the IMI ones but the EB4 bodies with 6 settings was cheaper

[MrPotts]

4 hours ago, Nickfromwales said:

So……they’re not actually auto-balancing then as they each require full mechanical (human) commissioning? I’m failing to see the benefit, sorry, and think it is much easier (for a newbie in particular) to get to the best result with balancing via the existing lock shield valve.

The latter is also the obvious choice in an existing install where you have the TRV’s (regular, serviceable ones) and do not want to make any changes.

 

@Dee, best to save your pennies and do this in one hit in the summer, as suggested above. Then you can take your time.

You use an app which tells you what setting to use based on the size and type of radiator.

[Dee]

I've calculated that it will cost £450 to change all valves and it's too costly in one hit. I'll persevere with manual balancing as too much could go wrong with my limited knowledge!

Those last two rads are about 20m from the boiler and the heat/ pressure/power just doesn't seem to be enough to get there....no oomph!

Someone suggested the expansion tank might be too small??

[marshian]

1 hour ago, Dee said:

I've calculated that it will cost £450 to change all valves and it's too costly in one hit. I'll persevere with manual balancing as too much could go wrong with my limited knowledge!

Those last two rads are about 20m from the boiler and the heat/ pressure/power just doesn't seem to be enough to get there....no oomph!

Someone suggested the expansion tank might be too small??

It only takes a few rads stealing a little too much flow to starve the furthest rads - benefits of those flow setting valves is that the flow is fixed at exactly what the rooms/rads need and no more.

 

how much do you value your time?

 

how much grief do you get for the rooms that aren’t getting warm 

 

Fully open circuit in my house and the pump is moving 0.5 m3/hr and that’s being shared out across 13 rads in a system with a total volume of 150 Litres (excluding HW)

[SteamyTea]

Would a second pump, closer to where the troublesome radiators are, solve the flow problem?

Pumps are cheap, and relatively easy to fit.

[Dee]

As tempting as it is to change the valves I think it's a step too far for me to attempt and as much as I woukd like yo try its likely to cost me more when I buggar something up!

I'll keep persevering with the current tedious method!

[SteamyTea]

In the days of old, when we all drove BL cars, balancing a set of SU carburettors was a challenge.

One way to do it was by listening down each inlet barrel and matching the pitch.

I am not sure of something similar can be done with water pipes, phones have useful sound analysis software on them these day.

[joe90]

2 hours ago, Dee said:

I'll keep persevering with the current tedious method!

Well done, it’s amazing how little a lockshield valve needs to be open on a rad near a boiler to heat up and steal from those furthest away. 

[marshian]

2 minutes ago, joe90 said:

Well done, it’s amazing how little a lockshield valve needs to be open on a rad near a boiler to heat up and steal from those furthest away. 

 

And that is why even though I could balance my system pretty well on cheap DIY lockshields I made the choice to invest in flow control TRV bodies or high quality lockshield valves with very linear performance characteristics because every time a TRV intervened it upset the system balance so found myself constantly tweaking and never happy

 

The high quality lockshields were more money than the flow control TRV bodies

[joe90]

2 hours ago, Dee said:

As tempting as it is to change the valves I think it's a step too far for me to attempt and as much as I woukd like yo try its likely to cost me more when I buggar something up!

It’s the OP,s choice. We can only advise.

[Dee]

I'm down to the last rad....furthest away from the boiler (by about 40 linear meters) that will not heat up.

I have tweaked, cajoled, threatened and pleaded with it but it will not yield to my will.

I just get the feeling there just isn't enough 'oomph' left in the pump to get there. 

Does it influence anything that the flow and return ftom the boiler goes to straight upto the floor void above and that the ground floor are solid. So all the pipes drop down to the rads below.

[marshian]

2 hours ago, Dee said:

I'm down to the last rad....furthest away from the boiler (by about 40 linear meters) that will not heat up.

I have tweaked, cajoled, threatened and pleaded with it but it will not yield to my will.

I just get the feeling there just isn't enough 'oomph' left in the pump to get there. 

Does it influence anything that the flow and return ftom the boiler goes to straight upto the floor void above and that the ground floor are solid. So all the pipes drop down to the rads below.

 

How open is the lockshield valve on that rad?

 

I don't think drop legs from a flow and return circuit above will make any difference but heat will always prefer to rise

 

Ages ago I got into a discussion with a chap who had a type of reverse return circuit for flow and return in the loft of his bungalow - all the pipes dropped down from ceiling to the rads

 

The last radiator fed with the flow was the first on the return leg

 

really high primary balance and all the lock shields were pretty much fully open

[Dee]

The return is almost fully open on Kitchen 1 rad ( the one im struggling with). I have tried every combination....shut off rad above and it gets a tad warmer, close the rad next to it ( Kit 2) and it gets a bit warmer still but not what I woukd call hot. 

On kit 1 the return pipe is much hotter than flow, like their reversed? Flow is about 37⁰c and return 52⁰c and both kitchen rads are vertical column type....I'm truely stumped. 

How critical is the order in which I balance each rad as its a big house and some rads seem to heat up very close in time so it's tricky to be sure I'm doing it in the right order.? 

[Dee]

I'm sure you've all had enough of me but I thought I would post the list of temps.

The temps on all but the furthest 2 rads in order they heat up are as follows;

(I put the rad temp in there for my own curiosity)

Boiler Flow 60    Rtn 50

Flow  Rtn             Rad

54     43                45

56     45                44

38     54*              41

44     40                45

57      45                45

45      52*             46

40      55*             40

54      40               43

54      51                50

43      29  study.   30

55      43               47

55      47               49

49      39               39

57      46               46

54      46               44

49      47               44

52      47                ??

44      41                40

51       39               39

??        ??

??        ??

I can't achieve 12⁰ drop on any of them 

Study won't heat atall and the last two (ground floor) won't heat up either.

Is there a pattern here or is it as good as it gets? 

* Rtn hotter than TRV

 

Thankyou as ever

 

[marshian]

41 minutes ago, Dee said:

I'm sure you've all had enough of me but I thought I would post the list of temps.

The temps on all but the furthest 2 rads in order they heat up are as follows;

(I put the rad temp in there for my own curiosity)

Boiler Flow 60    Rtn 50

Flow  Rtn             Rad

54     43                45

56     45                44

38     54*              41

44     40                45

57      45                45

45      52*             46

40      55*             40

54      40               43

54      51                50

43      29  study.   30

55      43               47

55      47               49

49      39               39

57      46               46

54      46               44

49      47               44

52      47                ??

44      41                40

51       39               39

??        ??

??        ??

I can't achieve 12⁰ drop on any of them 

Study won't heat atall and the last two (ground floor) won't heat up either.

Is there a pattern here or is it as good as it gets? 

* Rtn hotter than TRV

 

Thankyou as ever

 

 

Lot of data there to dissect but I'm going to start with the obvious - the TRV end might not always be the flow end

 

Example flow of two of my rads would mean the TRV would be tucked in a corner rather than in Free Air so more likely to turn the rad off before the room has reached temp so I deliberately put the TRV on the return end

 

So I would suggest that if you have a hotter end on the lock-shield end then that is the flow end and the TRV end is the return.

 

Second point - how are you measuring the temps (ie with what and where are you measuring on the rad)

 

I take 3 temp readings from every rad (all my rads are BBOE rather than the more efficient TBOE) with an hand held IR

 

4 of my rads are anthacite the rest are white and I get better readings from the dark rads - I did put black insulation tape on some of the white ones to improve accuracy but Mrs Marshian didn't like that approach at all.

 

Flow inlet - ie bottom of the rad where the flow pipe enters the rad

Top Middle - middle of the rad at the top

Return outlet - ie bottom of the rad where the return pipe leaves the rad

 

I take 3 measurements because depending on what the TRV is doing and what the boiler is doing often the middle top is the best guide to actual flow temp (Hot water rises so often the inlet area is actually slightly cooler) If I can format the results I'll share the readings I took from earlier this evening

 

Bear in mind (when I share the results) that this evening I was running a boiler flow temp of 32.5 Deg C and the return to the boiler was 25.0 Deg C

 

Even when I was running scheduled heating and 55 deg flow temps I could only get a couple of rads to beat 12 Deg C drop between flow and return and they were big 1400 x 600 T22 (Double panel double convector) rads

[marshian]

1 hour ago, Dee said:

I'm sure you've all had enough of me but I thought I would post the list of temps.

The temps on all but the furthest 2 rads in order they heat up are as follows;

(I put the rad temp in there for my own curiosity)

Boiler Flow 60    Rtn 50

Flow  Rtn             Rad

54     43                45

56     45                44

 

<Snip>

 

Thankyou as ever

 

So from left to right it's Rad Flow temp - Rad Return Temp and Rad Temp?

 

Rather than order they heat up in which is notoriously difficult to get - could you annotate them with Upstairs or Downstairs and Label them with the room

 

Here's what I use

 

[marshian]

Just to clarify - the boiler was no longer on a burn when the last radiator (Lounge) Flow and Return temps were taken and that rad has the highest flow rate of all the rads at ~1.2 Litres per min so it doesn't take long for the flow side to cool quickly

 

Also to add

 

Everything before Bed 1 is downstairs Circuit and after Front Hall is Upstairs Circuit - the whole house is one Zone for CH

 

Every radiator has flow restrictions in the TRV body and lockshield wide open I have a fairly good understanding of the flows to each rad

Edited 15 hours ago by marshian

[marshian]

Me trying to make sense of it (It's in the same order from top to bottom but I've fixed where flow and return were wrong and worked out the DT

 

Normally I'd say if the DT (Difference between flow and return was small there would be too much flow thro the rad but if the rad concerned is a towel rail then all bets are off because they are terrible for getting a decent drop between flow and return (they aren't much good as a heat emitter either IMO)

 

B. Flow	60
B. Return	50
Rad Flow	Rad Ret	DT	Rad??	Comments
54	43	11	45
56	45	11	44
54	38	16	41
44	40	4	45	What sort of Rad?
57	45	12	45
52	45	7	46
55	40	15	40
54	40	14	43
54	51	3	50	What sort of Rad?
43	29	14	30
55	43	12	47
55	47	8	49
49	39	10	39
57	46	11	46
54	46	8	44
49	47	2	44	What sort of Rad?
52	47	5	??	What sort of Rad?
44	41	3	40	What sort of Rad?
41	39	2	39	What sort of Rad?
??	??
??	??