Posted by: @egp01

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@jords I had very similar experience with heat loss surveys. I ended up having 4 🙄. Particularly noticeable was variation by rooms between them all and also the number of radiator changes and which rooms required radiator upgrades. I could find almost no consistency between them. This makes it incredibly confusing and tbh I did think about scrapping the idea of getting a heat pump altogether too. In the end I opted for an Adia system to be fitted with my heat pump - mainly because I can hold off on radiator changes and Adia will tell me what radiators I need to change based on the actual performance of my house and not "educated" guesses. I am already very interested to see what the real world data will show compared to the surveys, but will have to wait a while before I get the data from Adia. In the meantime - good news so far its keeping the house warm and isn't costing a fortune to run

To be honest every single heat loss in the UK is not fit for purpose, because a proper heat loss survey should combine airtightness testing with thermal imaging to provide a comprehensive understanding of energy loss. This is why, I would take the highest heat loss and go with that. As I mentioned, having oversized radiators is actually a great thing, as it allows for much lower flow.

Posted by: @drei

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I had a look at the Jaga Radiators, but at £800 for a 600 x 1200 Type 21 radiator is out of most people's price range, not to mention that hey are impossible to get in the UK with only a few distributors, these seem to be more of an American and Canadian thing.

Jaga is a Belgian company.  I ordered mine through Gogeothermal but the price you quote is about right with the DBH fan units installed (you can have them without fans when they use convection).  Delivery was about 6 weeks because they are made to order.

They have a few advantages that were important to us:

1  the heat output with fans is higher for a given size so you they take up less wall space

2  the fans have 3 speeds so you can vary the heat output without altering the flow through the rad

3  you can use them for "light cooling" with 16C chilled water in the summer

4  they are quiet

North American installations are generally entirely forced air, noisy, drying and completely different.

You get what you pay for.

Posted by: @downfield

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Posted by: @drei

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I had a look at the Jaga Radiators, but at £800 for a 600 x 1200 Type 21 radiator is out of most people's price range, not to mention that hey are impossible to get in the UK with only a few distributors, these seem to be more of an American and Canadian thing.

Jaga is a Belgian company.  I ordered mine through Gogeothermal but the price you quote is about right with the DBH fan units installed (you can have them without fans when they use convection).  Delivery was about 6 weeks because they are made to order.

They have a few advantages that were important to us:

1  the heat output with fans is higher for a given size so you they take up less wall space

2  the fans have 3 speeds so you can vary the heat output without altering the flow through the rad

3  you can use them for "light cooling" with 16C chilled water in the summer

4  they are quiet

North American installations are generally entirely forced air, noisy, drying and completely different.

You get what you pay for.

 

I had a look at the Jaga outputs and not impressed, they seem worse than the Type 22 and Type 31 panel radiators that cost half the price. One important question for me is, if they do cold in the summer and heat in winter, won't that cause condensation resulting in damp issues inside your floors and walls? What about thermal expansion/contraction potentially causing pipes to leak? I assume you need some serious full re-piping, with all the pipes dressed in insulating covers or whatever it is you can use to cover every mm of your pipes... but even then, would condensation not be an issue? If anything goes wrong with the fans, that have limited life expectancy what happens?

I think Heat Geeks used those bolt on fans for panel rads as an experiment, they did work, but in the end the difference was minimal.

Jaga 500 x 1000 Type 21 (thinner than the Panels Type 22 and Type 31) ∆t 50ºc BTU/Watts 8809/2582  = £657

Panel Radiator Type 31 600 x 1000 ∆t 50ºc BTU/Watts 8827/2587 = £326

Don't get me wrong, I looked at them because I need to replace all my radiators, and I do like the design. My remedial work is going to be around £15k with around £6000 in radiators, but I cannot justify £14k just in radiators that may or not actually have any benefit.

Not sure UK properties are fit for them, in Europe for example, they tend to put the pipes inside the cement, and house are differently built. This is one of our overall issue regarding Heat Pumps in the UK. European builds, especially Nordic countries, have a completely different quality. SkillBuilder did a few videos showing European builds and central heating designs over there.

Here you get a cardboard box, in Europe you get a bunker, and you can also access any property you buy blue prints from the local council, that shows you all the electrical work and all the plumbing. Miles ahead of the UK.

Dare I ask you, how much was your full Heat Pump system? Did EPC Improvements install your Jaga system too? Did they take any precaution in regards to condensation?

EPCI charged £12k after the grant for a 14kW system - so not cheap, as you say.

I did the Jaga rads separately and in 2 stages because we wanted make sure they worked Ok before fully committing.

They are much neater than conventional rads and provide a very even warmth throughout the property - we are mainly open plan downstairs so the trench rads - which are even more expensive - were important as we are limited for wall space.

Cooling - the rads can of course do full cooling with 7C water and have the facility for condensate drains if that's what you want and have suitably lagged pipework.

We don't and if you read the Jaga brochure they describe light cooling as not below 16C so you don't get any material condensation.  Obviously it varies depending on the humidity but it's easy to monitor and tweak the flow temp if necessary.

They've been installed for two summers now and we find they reduce the bedroom temps by about 5C which makes a noticeable difference.

incidentally the installer refused to implement the cooling option on the Ecodan controller so I had to do it myself, but it only required flipping 1 dip switch.

Posted by: @downfield

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EPCI charged £12k after the grant for a 14kW system - so not cheap, as you say.

I did the Jaga rads separately and in 2 stages because we wanted make sure they worked Ok before fully committing.

They are much neater than conventional rads and provide a very even warmth throughout the property - we are mainly open plan downstairs so the trench rads - which are even more expensive - were important as we are limited for wall space.

Cooling - the rads can of course do full cooling with 7C water and have the facility for condensate drains if that's what you want and have suitably lagged pipework.

We don't and if you read the Jaga brochure they describe light cooling as not below 16C so you don't get any material condensation.  Obviously it varies depending on the humidity but it's easy to monitor and tweak the flow temp if necessary.

They've been installed for two summers now and we find they reduce the bedroom temps by about 5C which makes a noticeable difference.

incidentally the installer refused to implement the cooling option on the Ecodan controller so I had to do it myself, but it only required flipping 1 dip switch.

 

 

 

That sounds really good, and something I could have done back when we had the Heat Pump installed as we had wooden floor installed afterwards, so everything was taken apart and easily accessible, which is my biggest gripe with EPC. Honestly I would be worried doing cold on my system and causing potential leaks. Saying that, I did ran the heat pump in cooling mode during the summer to see what it does, and yes the radiators started to drip water, so never bothered again.

We have the exact same issue with open plan downstairs, but we can't do any floor heating, as the previous owner replaced the carpet with marble, and I wish he would have put some thought into it, and just done underfloor heating throughout the ground floor. The cost to have done it when he laid the marble, would have been minimal and a huge benefit.

You mentioned that you did partial installation, how did that go? In my case, could I use Jaga Rads on the ground-floor only, where we have the highest heat loss and limited radiator wall space, and standard rads on the other floors?

What's the Jaga warranty on the fans, and do you know if they can just be replaced, or does it require a new radiators? From what you mentioned it sound like you get the radiators separately and the fans separately, and just put them together, or did I misunderstand? The online catalogue I looked at, seemed like the fans are part of the radiators internally.

SORRY TO HIJACK THE POST!!

I am hoping the original poster and other potential customer will find these beneficial. Especially if you want the best system for your money and wall space is limited, with no possibility of UFH.

Conventional Radiators that can do cold and hot, is something I wanted to have a look at, but I couldn't find much information back in 2023.

Posted by: @drei

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To be honest every single heat loss in the UK is not fit for purpose, because a proper heat loss survey should combine airtightness testing with thermal imaging to provide a comprehensive understanding of energy loss. This is why, I would take the highest heat loss and go with that. As I mentioned, having oversized radiators is actually a great thing, as it allows for much lower flow.

Whilst I wouldn't go so far as to say every heat loss survey is unfit for purpose, its entirely evident from what we hear here that many are unfit.  That's why I argue consistently for (as a bare minimum) am independent 'sanity check' based eg on measured consumption.  However every time I mention it someone comes out and finds reasons that things must stay as they are. 

My own story in essence was: 2 off 3 hr professional surveys came up with 16kW;  my own calculations using MCS assumptions and the correct fabric came to 10.5k; actual loss as verified both by gas consumption and subsequent HP production 7kW.  The difference between 16kW, on which most of the industry wanted me to base my system design, and 7kW, on which the system design was actually based, is massive and easily spotted by the simplest/crudest of sanity checks.

@scalextrix has recently done the training on heat loss surveys, perhaps he would like to comment why the current system is retained without any form of sanity check.

Posted by: @drei

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What's the Jaga warranty on the fans, and do you know if they can just be replaced, or does it require a new radiators?

Not sure about the warranty, but they are purchased separately and use a number of individual fans so probably could be repaired easily.  See 

https://jaga.com/uk/dbh/

I just found this blog where the poster is building his own fan units and putting them into the Jaga rads.

https://www.vanwerkhoven.org/blog/2021/diy-jaga-dbe-dbh/

The Jaga fan units look very similar but of course include the control gear that senses when the flow temp rises and turn on the fans.

Partial conversion:  we didn't notice any problems with mixing Jaga with conventional rads - never really thought about it.  You can run the Jagas at any flow temperature of course but they really pump out heat at 55C!  We run at between 35 and 40C on the weather comp curve.