Complicated Heating System (Air To Water)

[Lorien Rock]

Hi,

I moved into a new house this week, and I'm currently waiting on the manual for the heating system, which seems far more complex than any heating system I've used before

I've tried searching online for some information but it's hard to find any relevant information or guides.

I would really appreciate if someone could help with the following, thanks.

01 - Is an 'Air to Water' more cost efficient to run than a regular heating system?

02 - Should it be always running, or best to set it on timers (from what I understand it is constantly running and just keeps the temperature steady at all times?)

03 - Based on the short video I created below, has anyone ever come across this system / setup? Every room has a thermostat, but when I try increase the temperature it changes from SET to RT and then it seems like it takes a couple of days to climb to the temperature, so i'm completely lost with it.

Thank you in advance for your help.

 

[bernardgreen]

It appears to be a Heat Pump system

https://les.mitsubishielectric.co.uk/homeowners/our-heat-pumps

 

[stem]

I'm not familiar with this particular product, but I believe it is an 'air source heat pump' system [I have an older Mitsubishi ASHP] If so, the basic concept is that a compressor transfers heat from one place to another. So there will be an outside unit that gets cold and an indoor unit that gets warm.

ASHP units can be efficient to run, mine clams to be up to 300% which means it produces 3 times more heat than the energy it consumes. In reality the efficiency does fall as the temperature drops because there is obviously less heat in the outside air for it to collect. They also can't produce the high temperatures that a boiler can, so are usually used to provide warm air or underfloor heating (not radiators unless another heat source is provided also)

This means that they generally (especially with underfloor heating) should be left on 24/7 as they are slow to warm up, as you have found. If you have an off peak tariff during the night, then it can even work out cheaper to run than only having it on during the day and it having to run flat out to catch up.

 

[Lorien Rock]

Ok great, thank you both for your help, it's much appreciated. I will read up on that link on my lunch break.

Yes, it is an underfloor system, and we don't have any radiators... so does this mean that it is not possible to boost the heat for an hour on a cold night?

Also, I presume that this means you have constant hot water, it obviously heats the water too?

 

[stem]

I wouldn't have thought an hours boost would do anything, maybe in the warmer weather it might. You'll have to try it and see. At the moment with overnight temperatures of below zero ours is running 24/7 otherwise it won't keep up. When it's really cold the outdoor unit ices up and it can spend about a third of its time defrosting itself (no heat is produced whilst this is happening, although you won't notice due to the thermal mass of the floor, which can take as long to cool down as it does to warm up)

AFAIK ASHP's don't get hot enough to heat domestic hot water sufficiently for practical use (and to kill off legionella) so some additional hot water heating is normally provided, either to top it up, or as a completely independent standard electric hot water system (we have a unvented hot water cylinder and an immersion heater). Unless the ecodan (and it does looks impressive) has better technology.

 

[Lorien Rock]

Ok great, thanks... lots of reading to do

 

[muggles]

ASHPs are becoming pretty standard in new build houses now, with the Government drive to move away from gas boilers.

What controls do you have in the house?

 

[Lorien Rock]

Thanks Muggles. The only controls we have are in the video, and I've also added some photos below:

01 - Main Control (image below)

02 - Main Unit (also has controls)

03 - Thermostat (in each room)

 

[ianmcd]

Your system pressure is way to high at 3 Bar should only be around 1 Bar

 

[Lorien Rock]

Your system pressure is way to high at 3 Bar should only be around 1 Bar

Thanks, can you elaborate on what this mean, and how I could go about changing that?

 

[ianmcd]

Thanks, can you elaborate on what this mean, and how I could go about changing that?

that is the pressure that is in your underfloor heating system, it should be at 1 bar not 3, there is a drain point inside your unit, you could lower the pressure by opening that slightly, if you do and it goes back up to 3 you will need and engineer

 

[Lorien Rock]

Thanks ianmcd - is a going near the drain point, a good idea for someone like me?

Do I need to get a professional out to do it, or is this something I can do myself. If so, any direction on what this looks like etc. Sorry for what might seem like a silly question to you.

 

[RayCaister]

Don't touch it. It's a new house it must be under warranty. Get the installers out.

 

[ianmcd]

yes as @RayCaister says it should be under warranty so get them out