Balancing/heating issues

[Fadburty]

Hi all,

I have a Worcester Bosch 30 CDI combi boiler. I also have a megaflow installed in the loft.

The water temp on the boiler is redundant. As it is now controlled by the temp gauge on the megaflow. However, the radiator temp is on 6, if I reduce this it seems to disconnect the ignition spark and subsequently turn off the heating.

Also, I am trying to work out how to best balance the radiators. I have 10 in total.

Dinning room - closest to the boiler gets warm
Box room
Bedroom 2
Bedroom 3
Loft bedroom, then loft bathroom, followed by the front room downstairs and lastly middle room.

i saw instruction on this forum about how to approach this, however, I may be silly here what does 1/12 of a turn mean then increasing it? Should I not do 1/4 turns and increase in the order of the rads?

Also, the loft radiator only gets hot fully on TRV = 4, if it's on 2 only the top half gets hot.

At the moment the bathroom on the second floor doesn't get hot? Do I need to increase the turn on LS?

Lastly as mentioned I can not turn the rad temp on the boiler down, I saw the temperature last night hit 90 - is this worrying? ( I have reached the pressure on the boiler to 1.5bar by bleeding a rad)

 

[Knappers]

Put all trvs on full.
Close each lickshield and open 1 turn.
Run heating and open 1/4 to 1/2 turn more on coldest rads.
Very hot rads can be closed 1/4 turn.

Turn LHS nob for heating down to 5

 

[Fadburty]

Put all trvs on full.
Close each lickshield and open 1 turn.
Run heating and open 1/4 to 1/2 turn more on coldest rads.
Very hot rads can be closed 1/4 turn.

Turn LHS nob for heating down to 5

Thank you for the reply.

I feel like I have balanced it accordingly to order of the radiators. However the bottom two radiators take 20 mins to start getting warmer and 35 mins in total to be piping hot.

Surely this would be alot quicker?

The radiator in the passage way where the hive thermostat is. This doesn't have a TRV valve, should the LS be fully opened or adjusted according to the order???? Where there isn't a TRV valve I have no idea what level this should be at?

 

[ShaunCorbs]

Open them slightly up

Also 1/12 think of a turn like a clock face turn it either from 12-1 or 12-11 etc

The cylinder stat need turning up to 60 degrees instead of 38-40

 

[Knappers]

Do you feel like you've done to my instructions or to some imagined order of closeness or other instruction?
The way I'd quickly check is from cold and use heat dropping down rads as they warm to determine which ones to adjust.
If you have one or two slow ones then its not unreasonable to open them fully and try to adjust others down untill they heat at same speed.
I'd use Shauns 1/12th turns if your adjusting all rads at the same time and my 1/4turn if one rad is noticably too hot/cold.
I don't agree with cylinder temp needing to be at 60 (altho not wrong), I would have at atleast 50 tho.

 

[Fadburty]

Do you feel like you've done to my instructions or to some imagined order of closeness or other instruction?
The way I'd quickly check is from cold and use heat dropping down rads as they warm to determine which ones to adjust.
If you have one or two slow ones then its not unreasonable to open them fully and try to adjust others down untill they heat at same speed.
I'd use Shauns 1/12th turns if your adjusting all rads at the same time and my 1/4turn if one rad is noticably too hot/cold.
I don't agree with cylinder temp needing to be at 60 (altho not wrong), I would have at atleast 50 tho.

Hi,

Apologise what I did was discover the order the rads get hot, therefore I adjusted the LS from 1/4, 1/2,3/4, 1 full turn, 1 1/4 and so on.

With you method I understood it as turn all LS one full turn for all Rads. Then the rads getting too hot reduce then by a 1/4 and if there's is another hot rad reduce it by 1/2. Where as the other rads that need to be hotter increase it by 1/4 then 1/2 etc...? Is that correct?

The only rad I haven't adjusted is the rad in the hallway. This is where the thermostat is for the hive. There's two things; not sure which one is the LS and not sure if this one should be adjusted? Or can it be adjusted? Thanks

 

[Knappers]

Yes that's right, you can adjust hall rad but shouldn't turn off.

 

[king of pipes]

Your heating pump is only set at 75% capacity by the manufacturer out of the factory you may benefit from increasing this to 100% , you won't find how to do this in the installer manual though and it's a while since I've done it a quick call to Worcester technical and they will talk you through or it maybe best to go through customer service . Kop

 

[Fadburty]

Your heating pump is only set at 75% capacity by the manufacturer out of the factory you may benefit from increasing this to 100% , you won't find how to do this in the installer manual though and it's a while since I've done it a quick call to Worcester technical and they will talk you through or it maybe best to go through customer service . Kop

Hey, thanks for the reply. How did you know it was operating at 75%? Is this the case for most boilers?

I understand the boiler temp should be above 60 degrees to avoid legionela. The water thermostat on the Megaflow. What temperature should this be at?

Since lowering the rad temp on the boiler so it doesn't go over 80degrees. I have noticed lower temp on the hot shower which was surprising. As this shouldn't impact the taps? Anyways should the temp on the Megaflow be above 60 too to avoid legionela? Thanks

 

[ShaunCorbs]

The boiler should be above 60c so you shouldn’t feel a difference unless it’s below this

 

[Fadburty]

The boiler should be above 60c so you shouldn’t feel a difference unless it’s below this

Interestingly the downstairs tap is connected directly to the boiler so I reduced the water thermostat on the boiler. I feel this thermostat may potentially have a part to play.

Should the Megaflow temp be at 60 degrees too?

 

[ShaunCorbs]

Yes so the flow pipe out of the boiler heating side needs to be 65dc

 

[king of pipes]

Hey, thanks for the reply. How did you know it was operating at 75%? Is this the case for most boilers?

I understand the boiler temp should be above 60 degrees to avoid legionela. The water thermostat on the Megaflow. What temperature should this be at?

Since lowering the rad temp on the boiler so it doesn't go over 80degrees. I have noticed lower temp on the hot shower which was surprising. As this shouldn't impact the taps? Anyways should the temp on the Megaflow be above 60 too to avoid legionela? Thanks

Yes it's the case for Worcester boilers and others , with a Mega flow I would recommend 65°c minimum boiler temperature not so much for legionella but to fully heat your cylinder and switch off at 60 °c which your Megaflo thermostat would-be set at , once satisfied the 2 port motorised valve closes and the boiler stops the pump runs for 3 min to dissipate the heat before switching off .

 

[Fadburty]

Yes so the flow pipe out of the boiler heating side needs to be 65dc

Sorry Shaun - just for clarity are you saying the Megaflow cylinder should be above 60 degrees? (Attached a picture what the temp is at)

I understand the combi boiler should be 65dc.

 

[ShaunCorbs]

Yes that should be the higher side of the 60 mark

 

[Timmy D]

Due to valve authority (google it), most standard lock shield valves only adjust flow on the first full revolution (maybe 1.5 revolutions). So what I’m saying is there is no difference between 2 full turns and 5.

All your balancing wants to be done between closed and open by 1 turn.

Also, your cylinder should have a recirc pump even if you don’t have a recirc line due to increased stratification on horizontal cylinders. I’m pretty certain it’s in the manufactures instructions for that cylinder.