Newbie out of her depth – Samsung AE120RXYDEG 12kW heat pump - Air Source Heat Pumps (ASHPs)

RE: Newbie out of her depth – Samsung AE120RXYDEG 12kW heat pump

BAMi — Sat, 22 Mar 2025 10:00:05 +0000

Update for those following this thread.

Finally got the 'tech guy' from the installers to email me. I sent him the plan the surveyor had done, which was completely wrong, and the plan I've done which is correct.

He is trying to tell me that the plan I was sent was just to show the rad sizes and pipe positions and has nothing to do with the heat loss calculation (which I haven't been sent).

I told him that if the BTU for rad sizes has been calculated off the surveyor plan he sent me, in which the room sizes are incorrect, windows are missing and it shows a heat loss outside wall which doesn't exist, how on earth can the rad sizes be correct. He's still saying they are - which is nonsense. For starters, the utility is 6.48 m2 and has a 70cm x 80cm radiator, while BR3 is twice the size at 12.24 m2 but only has a 70 x 50cm radiator. BR3 is always cold.

I asked if the heat loss calculation was done via a different house floor plan and if so why? No response to that! I've now asked for the heat loss calc and the house plan that was done off. Will see if I receive it.

He has arranged to come for a visit this Friday, so I'll report back after that.

I don't want to tamper with too much until he's been, but did check the rad valves in the lounge (which is always chilly) and they were closed by a 4.5 turns! So I've opened both up to max and the rads are definitely getting warmer in there - thanks for this advice.

RE: Newbie out of her depth – Samsung AE120RXYDEG 12kW heat pump

JamesPa — Tue, 11 Mar 2025 18:06:17 +0000

Apart from putting the DHW on a timer, and altering the low end of the weather comp to -2C from 2C the system is as it was commissioned - for now at any rate.

No pressure or obligation, this discussion has moved on so much I felt it worth restating in case you had missed it.

Installers will probably say touch nothing, which eventually you may have to ignore, but you are imho right to be cautious while you are trying to get them to change things!

RE: Newbie out of her depth – Samsung AE120RXYDEG 12kW heat pump

BAMi — Tue, 11 Mar 2025 17:45:23 +0000

@jamespa I haven't forgotten 🙂 But I want to talk to the tech chap at the installers before I start altering the system, just so they can't accuse ME of being the reason the system isn't running efficiently.

Apart from putting the DHW on a timer, and altering the low end of the weather comp to -2C from 2C the system is as it was commissioned - for now at any rate.

RE: Newbie out of her depth – Samsung AE120RXYDEG 12kW heat pump

bontwoody — Tue, 11 Mar 2025 17:44:56 +0000

@jamespa @bami

Just to clarify, I have already done what James has suggested. My water law settings are as low as I can use.

RE: Newbie out of her depth – Samsung AE120RXYDEG 12kW heat pump

JamesPa — Tue, 11 Mar 2025 17:13:10 +0000

But like Bontwoody I also have a house thermostat which tells the pump what time to set back and when to come on if house temp gets too low

Don't lose sight of the fact that at some point to optimise your settings, I recommend to turn this to max and 24*7 operation then adjust your water law curve down. I suggested a procedure quite some posts ago. Your choice of course but lowest possible flow temperature=lowest operating cost and greatest comfort in most cases, and is definitely the place to start.

RE: Newbie out of her depth – Samsung AE120RXYDEG 12kW heat pump

BAMi — Tue, 11 Mar 2025 16:59:46 +0000

@broadsman Not the faintest clue! When I read about how to change the water law settings it never mentioned changing the Heat to Auto, so I've just left it on Heat.

But like Bontwoody I also have a house thermostat which tells the pump what time to set back and when to come on if house temp gets too low.

I'll ask the installer tech guy if he ever gets back to me!

RE: Newbie out of her depth – Samsung AE120RXYDEG 12kW heat pump

bontwoody — Tue, 11 Mar 2025 11:38:33 +0000

@broadsman I run mine on water law but with regards thermostat as a limiter on my warmest room so the controller does display HEAT.

RE: Newbie out of her depth – Samsung AE120RXYDEG 12kW heat pump

Broadsman — Tue, 11 Mar 2025 10:50:07 +0000

To Bami and others with Samsung pumps. I notice that the controller is set to "Heat". Is this correct, or should it be set to"Auto" for Water Law (as is mine)?

RE: Newbie out of her depth – Samsung AE120RXYDEG 12kW heat pump

bontwoody — Tue, 11 Mar 2025 09:29:01 +0000

@bami I think a lot of people use heatpunk as a heat loss calculator. To me 6kW would sound about right but this is an area where installers regularly over size their systems often due to an over estimate of air changes per hour. I would guess that the majority of people get an oversized heat pump to a varying degree and getting any redress is incredibly difficult in the current system.

RE: Newbie out of her depth – Samsung AE120RXYDEG 12kW heat pump

BAMi — Tue, 11 Mar 2025 09:11:20 +0000

@jamespa
@bontwoody

I can't just input the proper floor areas on the installer calc as he missed out 2 windows and patio doors. So I used this online calculator (don't know if it's the correct one but it asks the right questions re floors, walls and window areas)
https://www.plumbnation.co.uk/heating-calculator

Using this calculator, heat requirements come out at 5460.94 watts, so do I assume from that a 6KW pump would suffice?

I'm going to ask the installers to re-do the heat loss calculation and we'll see what the outcome is.