Design Temperatures and Radiator Sizing

[nhp (nigel pendall)]

Yes - thats the one - thanks, for some reason I had difficulty finding it again. Getting old.

[sunshine_rag]

It’s hard to get a picture of the back of the radiators, I see there are two separate tubes going into the walls. Tried to show it in the picture below

Does this confirm the pipe layout for hot/cold is separate ?

Also,
This is one of the newer radiators. You can see some differences to the old one in the kitchen. There is a grill. Does that have any relevance? Are there any advantages to go with these radiators everywhere. Or are radiators effectiveness only depend on their type K1, K2, fin no fin.?

[sunshine_rag]

@Jonathan

Hopefully it is balancing as its fairly easily resolved with some trial and error. I would be tempted to turn the thermostat up really high (like 25-30C) so it is always calling for heat. This removes it as a factor, if the kitchen gets to your desired temperature with the thermostat really high then you know the radiator is capable of it and you need to focus on the thermostat/hallway problem.

With tweaking lockshields both the hallway (turn down), and kitchen (turn up), I managed to get the kitchen to 20.6ish after sometime.

Thermostat was at 22 throughout.

I still suspect somehow the kitchen radiators are not getting enough flow. But I will hold on assessing that deeper. For now I am going around the house and noting down the lock shield positions in other floors.

[SarahH (Sarah Hanson)]

Hi @sunshine_rag,

1. It looks like you have microbore radiator flow/return pipework. This can make radiator balancing slightly more tricky because of the increased pressure drop, especially for radiators at the far end of the system.

@sunshine_rag

There is a grill.

If you are referring to the radiator top grill, this seems to have negligible effect on heat output - see Radiator Balancing - is there an idiots guide? post #51.

[sunshine_rag]

Thank you @SarahH and @nhp , I have the experiment ongoing How did you optimise your heat pump schedule for comfort and cost? - #7 by sunshine_rag

[sunshine_rag]

@SarahH

It looks like you have microbore radiator flow/return pipework. This can make radiator balancing slightly more tricky because of the increased pressure drop, especially for radiators at the far end of the system.

Interesting. Going further into the rabbit hole . Of note, this is the new radiator done as part of the heat pump install., I will try to snap a picture of the older one, is it possible each radiators have different type of pipework and that has an impact on balancing?

@SarahH

If you are referring to the radiator top grill, this seems to have negligible effect on heat output - see Radiator Balancing - is there an idiots guide? post #51.

Signed up.

[Jonathan (Jonathan Frye)]

It sounds like you are making good forwards progress and you can probably resolve your problems with radiator balancing.

Your pipework in the photo looks as per normal so I think we can discount hot/cold being the same pipe.

@sunshine_rag

I still suspect somehow the kitchen radiators are not getting enough flow. But I will hold on assessing that deeper. For now I am going around the house and noting down the lock shield positions in other floors.

I suspect this too. @SarahH notes the microbore pipework and how the length of pipework to different radiators can alter their flow.

You have the kitchen radiator fully open now, so your remaining adjustment is to partially close other radiators with the goal of directing flow towards the kitchen radiator.

[sunshine_rag]

Yes @Jonathan and all others who contributed to this thread . this has been very helpful. I will continue updating this if there is any new findings, hopefully it will be useful to others too.