Heat Pumps - post here.

championc

Because plumbers should stick to the physical side, and leave the commissioning to heating engineers 😕

FastFullBack

https://www.boards.ie/discussion/comment/121666970#Comment_121666970

Where would a Shelly EM be installed? At the fuse box or would it be somehow attached to heat pump?

HotSwap

https://www.boards.ie/discussion/comment/121668782#Comment_121668782

Yeah. You are 3.25 so far today. 3.15 yesterday. 2.5 on Tuesday. Etc…

I would advise you to take note of these values on a weekly basis and make a spreadsheet for yourself to track them. Along with the average outdoor temp on that day (grab that from electric Ireland).

There is definitely some room for improvement; you could be getting better than 3.25 today as it’s quite mild out.

you need to keep bringing down that flow temp curve (or just set it static flow temp to remove some of the complexity) and note what date you make a change and then wait a week and see if the house is still warm enough and had the COP improved.

it’s a joke really that you would be handed a system that hasn’t been commissioned correctly.

grahamt311

Thanks for all the help, at least I know how to track the progress now to see if I'm making it better or worse. The thing with the flow temp is I have the lower end set at 35 degress at 15 degrees outside, any lower than that the radiators don't even feel warm. Should I lower that temp and see what happens. I just checked there today I'm up to 3.42 now, obviously because it 13 degress outside. Should the system COP drop by much in the cold weather. Also how low can the radiator work and still be effective

Yeah I know, I never even got a cert to say it was installed correctly. I lost faith in the plumbers with the work they done on the regular plumbing. And then when asked how to operate the system they didn't seem to have much knowledge either.

Now my wife thinks I'm obsessed with it, and her opinion is why would the installer not set it up right

championc

Just another thing to check - what is your delta-T ?

Delta-T is the difference in temperature between the flow and return at the heatpump. It should be around 5 Deg C

newhouse87

https://www.boards.ie/discussion/comment/121670781#Comment_121670781

Haha think most ourpartners think the same. My plumber was same, it was commissioned by daikin and got cert but that guy told me zero and had settings way too high which cost a fortune MY first winter last year. You would be hoping cop 4_5 in this weather. Can be below 3 in real cold weather,defrost cycles are a killer. It's all about getting lowest flow temperatures while maintaining desired heat. Some people run 24/7 by having stat calling for heat constantly, others by stats switching heatpump on and off and some of us by running for setperiods throughout the day and off at night. Have to figure out what suits your house best.

grahamt311

So I've been running mine 24/7 and stats turning it on and off. I'll just keep changing it up and see what effect it has. I suppose in the grand scheme of things always having a warm house and hot water would never be as cheap as only running gas for a hour in the morning and 2 hours in the evening.

HotSwap

https://www.boards.ie/discussion/comment/121670781#Comment_121670781

Don’t get too hung up on rads not feeling as hot as your used to when you touch them; focus more on are the rooms at a comfortable temperature. Can you show us what kinda rads you have? Are they standard metal rads with fins or the new aluminium ones? This will answer your question about how effective they are at lower temps.

To get the most out of it you need to keep pushing it lower until you start to feel that the rooms are not warm enough at that point you know it’s too low and can bump it up a tiny amount to get you back to a comfortable level. So defo lower it and see what happens. Otherwise you will never know.

The COP will always drop down when the temps outside reach the low single digits and below 0c. Not a lot can be done about that. But those are the days when you will really find out if your flow temp (technailly called LWT on heat pumps - leaving water temp) are too low.

You’re doing the right thing; if your wife wants to pay the electricity bills let her. But what you’re doing now will potentially save you 1000’s of euro in the life of the system. So fair play.

HotSwap

https://www.boards.ie/discussion/comment/121671124#Comment_121671124

I mentioned it above but you would be better off setting them stats to a much higher temp; such that they are never coming into play and telling the heatpump to turn off.

You should be aiming to have the heatpump alone (by varying its flow temp - based on outside temp / weather comp) dictate the temp of your rooms.

the longer and lower the heat pump runs the better your cop will be.

if them room stats are kicking in and telling the heatpump to turn off ; that just tells you the flow temp is too high and could be reduced.

HotSwap

https://www.boards.ie/discussion/comment/121671363#Comment_121671363

I’m making the assumption here that these are dumb stats that are controlling a zone valve; rather than stats that are actively communicating back with the heatpump.

if they are communicating back with the heatpump what I said is not a good approach; as this can have the impact of increasing the flow temp curve. Usually there is a setting the enable or disable “room effect”. Which will stop the stats from modifying the curve.

the more you dig the more there is to know. But if you keep it up you’ll be on here soon dishing out the advice.

grahamt311

The radiator are just normal oversized radiators I think. And the stats are just dumb stats. When the flow temp gets to around 30 the radiator feel have no heat off them at all. I will lower I'd down to 30 degress at 15 outside and see what happens over the next few days

zoom_cool

https://www.boards.ie/discussion/comment/121671567#Comment_121671567

I have Alu Rads and need about 33 to start feeling anything to be honest but then my Rads are not oversized. I run a constant fixed flow of 35 and fine this works for my setup.

dominatinMC

https://www.boards.ie/discussion/comment/121671567#Comment_121671567

They are standard steel rads? Heat pumps work better with oversized Aluminum rads to compensate for the lower flow temps. But these ones should do the job too, albeit at a higher flow temp.

If you're setting your HP flow temp to 30, it's likely the rads are only seeing ~25 degC, as there is bound to be temp drops along the way. So maybe just be mindful of that. However, as another poster mentioned, don't worry too much about the rads "feeling hot". In a HP system, the rads are emitting low temperature heat over a long time period, so they shouldn't necessarily feel hot. Ultimately, if the room is reaching the desired temp, the rads are doing their job.

chuckles1

https://www.boards.ie/discussion/comment/121660018#Comment_121660018

so no cooking and no lights?

bauney

Hi all, after coming back from a weeks holiday my daikin air to water hear pump (split) was not working. Installed back in 2012. It had tripped the switch, when i flicked the trip switch, it tried to come on and it showed up a PJ error code for a couple of mins and then it shorted again. I repeated this a couple of times and same result.

As per documentation PJ means "Improper combination between inverter and fan driver"

I presume the storms we had in Mayo (apparently very very gusty) last week caused some issue with the outdoor unit.

Unfortunately our backup immersion attached to the tank is not working so we are without heat or hot water 😩.

Any one face this issue?

championc

Could be wrong but sounds like the outdoor unit is off, or needs to be reset. I think the outdoor needs to be running for a few mins before turning on the indoor unit (assuming the inverter is indoors and the fan unit outdoors)

dominatinMC

Not trying to be smart but, have you tried turning it off and on again? There should be an isolator beside the outside unit, I'd try switching that off for 5 mins, then on again to see if the unit resets. Just a thought.

gandalfio

Seeking some advice. Samsung heat pump with Kodiak/Joule cylinder/stats.

Water temperature in the cylinder is randomly dropping for no apparent reason. Target temp is 48, when temp drops below 43 heat pump begins to heat the water back up to 48. I understand that when the cylinder is heating back up to 48, the heating won't work as DHW is prioritised. No issues there.

Yesterday there were no showers, baths, running hot taps etc until a quick shower around 5pm. After the shower I noticed the stats were calling for heat but rads were cold.

Checked the panel on the unit and water temperature was 35.6. Surely the quick shower couldn't have made the temp go below 43 all the way to 35?

I've monitored it before and quick showers usually only make the temperature drop by up to 1 degree max.

When the heating is on, does it draw water from the cylinder and can this cause the temperature to reduce? Can't think of anything else.

It then took an eternity to heat back up to 48 before our heating could come back on.

dominatinMC

https://www.boards.ie/discussion/comment/121704404#Comment_121704404

It begs the question, how "quick" was the shower?! I know my wife and I differ greatly on the definition of a "quick shower" (20 mins v 5 mins)! 😅 But seriously, that temperature drop is not unusual if you are in the shower for 10 mins or so. And also greatly depends on the size of your hot water tank.

Where you said you've monitored it before, how long after a shower did you check the temperature? There could be a delay in the signal to the panel. So if you checked immediately after the shower, it looks as if the temp has only dropped by a degree or so, but if you checked 15 mins after the shower, you might see a more realistic reading.

Also, I doubt the heating is drawing water from the cylinder. From my understanding of heat pumps, this shouldn't happen.

gandalfio

https://www.boards.ie/discussion/comment/121704436#Comment_121704436

5 minutes. I've checked it many times just after a shower and then again a few minutes later and very small drop, less than a degree. But if you say it's normal to also drop so much, that's good to hear. It just seems random to me.

gandalfio

Another issue we're experiencing is while the tank is heating back up to 48 (meaning the heating can't come on) and if either of the stats call for heat, the temperature reading on the stat will climb as if the heating has come on. Even though the rads are cold and the heating is 100% not on. Has anyone else experienced this?

Eleusis

https://www.boards.ie/discussion/comment/121704404#Comment_121704404

Depends on the size of your tank too. I'm not sure exactly but I have a 200l and it could easily use approx 10 degrees on a 5 min shower. I think your 1© drop for a quick shower must be incorrect. That's 20 odd 5 mins showers from 50 degrees to 30 degrees. Insane

newhouse87

Isn't the probe located near bottom of cylinder where the water is coldest as cold water fed in to replace warm water taken from top, doesn't mean the whole tank temperature has dropped, why I stopped scheduled reheat on mine as even 20deg reading was warm Enough for shower

MacDanger

IMG_20240203_134621.jpg

Have a Samsung heatpump in a new build and there's a decent amount of water (condensation?) coming from it; just checking if that's fairly normal or what?

ColemanY2K

https://www.boards.ie/discussion/comment/121729398#Comment_121729398

completely normal. we put an aco drain under ours as per the advice from the plumber. we live in an area with high levels of iron and maganese which would quickly turn the footpath brown if the water wasn't captured and siphoned away.

graememk

https://www.boards.ie/discussion/comment/121729487#Comment_121729487

But the water from the heatpump is condensation/frost it's basically distilled water, it wouldn't have iron or maganese.. unless it would leech from the concrete?

ColemanY2K

https://www.boards.ie/discussion/comment/121729680#Comment_121729680

i'm only going by what the plumber said. perhaps the browness has nothing to do with the mineral content and i've just got my wires crossed with the two issues we have here.

graememk

https://www.boards.ie/discussion/comment/121729967#Comment_121729967

I would agree with the drain though, Stops it from piddling all over the concrete.

funnyname

We need to replace an old clapped out ground source HP. The old one is currently in a small shed at the side of the house. There is plenty of room in the plant room (location of the thermal store and manifold) in the house, so just wondering would it be a good idea to place the new HP in here rather than out in the shed? Thinking it will reduce the heat losses and give me back some room in the shed as I doubt the new HP would be that loud?

ewj1978

quick one. Ive a relation up north that can get me a HP vat free. Would this still qualify for the SEAI grant?