NSS Posted July 22, 2019 Share Posted July 22, 2019 For the first time since we moved in, I've turned on the active cooling to our floor tonight. With the projected high temperatures for the next couple of days, and the current high humidity level, I thought I'd see how effective it is. Floor temp prior to activating was circa 23.7C. Water temp leaving the ASHP is currently 9C. Link to comment Share on other sites More sharing options...
ProDave Posted July 22, 2019 Share Posted July 22, 2019 What is your floor make up? I have been tempted to fire mine up in cooling mode, but worry an Oak floor laid on a biscuit mix might not be happy if there starts to be condensation anywhere. Even though we are in the Highlands, it's 23 degrees in the bedrooms right now. I can feel a night purge coming on when we go to bed and lights out. Link to comment Share on other sites More sharing options...
Jeremy Harris Posted July 22, 2019 Share Posted July 22, 2019 We find that floor cooling works really well downstairs, it's upstairs (where we don't have UFH) that tends to stay a bit too warm (I'm hoping to commission the air con in our bedroom tomorrow). Be very interested to find out how you get on with floor cooling @NSS, as I think that @jack and myself are the only ones here that have tried it so far. Link to comment Share on other sites More sharing options...
NSS Posted July 22, 2019 Author Share Posted July 22, 2019 10 minutes ago, ProDave said: What is your floor make up? I have been tempted to fire mine up in cooling mode, but worry an Oak floor laid on a biscuit mix might not be happy if there starts to be condensation anywhere. Even though we are in the Highlands, it's 23 degrees in the bedrooms right now. I can feel a night purge coming on when we go to bed and lights out. We have 70mm of fibre-reinforced concrete over a Hanson Jetfloor. We only have one bedroom upstairs but we have a Panasonic air-rad in that room so have spot cooling when we need it (activated tonight for the first time this year but was very effective last summer when needed). Link to comment Share on other sites More sharing options...
NSS Posted July 22, 2019 Author Share Posted July 22, 2019 16 minutes ago, JSHarris said: We find that floor cooling works really well downstairs, it's upstairs (where we don't have UFH) that tends to stay a bit too warm (I'm hoping to commission the air con in our bedroom tomorrow). Be very interested to find out how you get on with floor cooling @NSS, as I think that @jack and myself are the only ones here that have tried it so far. I'll let you know in due course, but one interesting observation already. I initially activated the air-rad only. It's circuit contains a relatively low volume of water so cooled quickly. Since turning on 6 of the 11 ufh circuits (approx 650m of pipe) the temperature of water leaving the ASHP has crept up (currently at 18C) but this presumably is because it is now circulating a far greater volume through a slab that was comparatively warm. Link to comment Share on other sites More sharing options...
NSS Posted July 22, 2019 Author Share Posted July 22, 2019 Actually, scratch the above, the circuits haven't actually opened on the manifold. Some late night reading of the operating instructions is called for ☹️ Link to comment Share on other sites More sharing options...
ToughButterCup Posted July 23, 2019 Share Posted July 23, 2019 Interesting thread. I haven't installed any MVHR yet. The majority of windows are openers - and since I'm working inside all of them are open : plaster drying off everywhere. Its a relief to be working indoors in a bit of a breeze. And whether or not it's actually cooler (I suspect the air temperature is exactly the same inside as out) , it feels cooler. And maybe that's the main thing in the summer months. Link to comment Share on other sites More sharing options...
ProDave Posted July 23, 2019 Share Posted July 23, 2019 9 hours ago, NSS said: Actually, scratch the above, the circuits haven't actually opened on the manifold. Some late night reading of the operating instructions is called for ☹️ Mine is only really set up for heating. If I wanted to cool the floor, I would have to go and switch the ASHP to cooling mode on it's control panel, and then go and turn the heating programmer to on, and turn all the room thermostats up to stupidly high temperatures as all the controls assume heating mode and at the moment all the room thermostats would be turned off. If you were regularly going to use it for cooling you would want to re think the controls somewhat. Link to comment Share on other sites More sharing options...
Jeremy Harris Posted July 23, 2019 Share Posted July 23, 2019 I split the controls on ours, so the "turn on the UFH actuator" line is separate from the "call for heating" line. We also have two room stats, one set up for cooling and one for heating. The control lines we have are: Timer - has overall control of on and off times for the whole system, also switches the circulating pump on and off UFH on - turns on the UFH actuator, either for heating or cooling, or turns it off Call for heating - puts the ASHP in heating mode and turns it on Call for cooling - puts the ASHP in cooling mode and turns it on We also have a DHW pre-heat mode, controlled by a tank stat on the buffer, that ensures that the UFH circuit is off if cooling mode is active, before switching the ASHP to heating mode to heat the tank. I'll probably bin this, and the buffer tank, next time I drain the system down, as it's not needed and we've had the pre-heat tank stat turned off for months not. Link to comment Share on other sites More sharing options...
Jeremy Harris Posted July 23, 2019 Share Posted July 23, 2019 11 hours ago, ProDave said: What is your floor make up? I have been tempted to fire mine up in cooling mode, but worry an Oak floor laid on a biscuit mix might not be happy if there starts to be condensation anywhere. Even though we are in the Highlands, it's 23 degrees in the bedrooms right now. I can feel a night purge coming on when we go to bed and lights out. I don't think you'd have a problem with the flooring, @ProDave. Our floor cooling has been on most of yesterday, it's just come on again this morning, and I've been around and measured the floor surface temperature and it varies from 18.9°C on the travertine to 19.5°C on the bamboo flooring. The RH inside would need to be over 75% for there to be any significant risk of condensation on the flooring, and currently the RH is sitting at about 49%. I don't think I've ever seen the RH downstairs get above 60%, it's usually down around 40%. I think it's a bit higher this morning because it was really misty here first thing (just radiation fog from it being a clear night, and our location in a deep valley, next to a stream). Link to comment Share on other sites More sharing options...
jack Posted July 23, 2019 Share Posted July 23, 2019 I just turn ours on by hitting the "mode" button on the standard controller. Normally at this time of the year it just does hot water, but by cycling through modes I put it into hot water/cooling mode during hot weather. I leave it on during the daylight hours so it mostly runs off PV, and turn it off in the evening. Downstairs in our house is very pleasant at the moment. Probably about 20 deg C. Upstairs is getting a little uncomfortable - I had to get up and open a window at 3 o'clock this morning because it was too warm even with no sheet over me (my wife was sleeping soundly under a duvet!) It's time to start paying more attention to purge cooling in the early evening and mornings again. Link to comment Share on other sites More sharing options...
ProDave Posted July 23, 2019 Share Posted July 23, 2019 Okay I hit a problem trying cooling on ours. I tried to set cooling mode on the LG controller, but it would not allow me to select that option. So I dug out the manual. I find that "cooling" mode is not available when you have opted to use an external room thermostat input. I use the room thermostat input as that is what allows me to control the heating from a normal programmer using the "call for heat" contact from the UFH manifold as the "thermostat" contact to the ASHP. To disable the room thermostat option (and thus allow cooling mode) would require opening up the ASHP and changing a DIP switch on the controller board. It is not even a software parameter that you can change. A future mod, when I can be bothered will be to connect that particular DIP switch to something more accessible, even a waterproof outdoor switch mounted on the outside of the ASHP would do it. Of course doing so would mean soldering 2 wires onto the back of the controller board and would invalidate any warranty I am sure. I have said before, the difference between one ASHP and another is in the detail of how they implement their controls, and I have to say the LG one that I have is very poor in the way it interfaces to the real world and the silly obstacles it throws in the way. Of course unless you ask other users who know it in detail you won't find this out until after you have bought the unit. And the silly bit, it even has a separate input for a cooling thermostat, separate to the heating thermostat input. One assumes that would still work if I disable the heating thermostat input and then set it to cooling mode. I think I said before, I get the feeling I have the V1A beta software in my unit with much room for improvement. Link to comment Share on other sites More sharing options...
Jeremy Harris Posted July 23, 2019 Share Posted July 23, 2019 The controller for our ASHP is a bit of a nightmare, the user interface is really dire. I opted to set it up so that the controller is only used as a programmer, with the control of the ASHP operating modes being by dry contacts. Our outdoor unit has separate dry contacts for ASHP on, cooling or heating mode, DHW mode, and quiet/eco mode. By just connecting dry contacts to 0V the unit can be made to switch on in heating mode, cooling mode, DHW mode or quiet mode (in addition to the other modes). Makes it fairly easy to control, but needless to say none of this is documented well; I had to reverse engineer the thing and then experiment to find out how it really worked. I made up a relay box, with a bit of simple diode logic, to translate the various combinations of thermostat and timer inputs to dry contact outputs that just run via a multicore cable to the ASHP. It's easy enough to change this fairly easily, plus I used DIN rail mount relays, with LED indicator bases, and fitted them inside a small consumer unit box, that has a clear lid. This makes it easy to see what's going on, just by looking at which LEDs are lit. Link to comment Share on other sites More sharing options...
NSS Posted July 23, 2019 Author Share Posted July 23, 2019 Update: I tried increasing the room stat temps and sure enough it then 'calls for heat' and opens the manifold valves but seems just to circulate the water that's in the pipes (no cooling). Awaiting a call from Panasonic tech support. Link to comment Share on other sites More sharing options...
ProDave Posted July 23, 2019 Share Posted July 23, 2019 14 minutes ago, JSHarris said: The controller for our ASHP is a bit of a nightmare, the user interface is really dire. I opted to set it up so that the controller is only used as a programmer, with the control of the ASHP operating modes being by dry contacts. Our outdoor unit has separate dry contacts for ASHP on, cooling or heating mode, DHW mode, and quiet/eco mode. By just connecting dry contacts to 0V the unit can be made to switch on in heating mode, cooling mode, DHW mode or quiet mode (in addition to the other modes). Makes it fairly easy to control, but needless to say none of this is documented well; I had to reverse engineer the thing and then experiment to find out how it really worked. I made up a relay box, with a bit of simple diode logic, to translate the various combinations of thermostat and timer inputs to dry contact outputs that just run via a multicore cable to the ASHP. It's easy enough to change this fairly easily, plus I used DIN rail mount relays, with LED indicator bases, and fitted them inside a small consumer unit box, that has a clear lid. This makes it easy to see what's going on, just by looking at which LEDs are lit. Yes your unit seems much better thought out. My LG unit has very few "user" inputs so I don't have that flexibility it all has to be done via the silly controller, and as I say some things even need DIP switch settings changed. This is the sort of thing you need to know before you choose a particular unit, not find out afterwards. But of course you won't find that info in the sales brochure. Link to comment Share on other sites More sharing options...
Jeremy Harris Posted July 23, 2019 Share Posted July 23, 2019 I hope you've managed to get your floor cooling going, @NSS. We've just hit 30°C here, and the temperature is still rising, the forecast seems to suggest it will peak sometime in the late afternoon. At the moment the floor cooling is holding the downstairs temperature at around 22°C (it was around 21°C first thing) but upstairs is over 23° and heading for 24°+ I suspect. I've just finished vacuuming down the new air conditioning system, just need to wait while I have lunch to see if there are any leaks, then, with luck, I may be able to get it working to cool down our bedroom for tonight. Certainly a good day to test it! Link to comment Share on other sites More sharing options...
JanetE Posted July 23, 2019 Share Posted July 23, 2019 @NSS haven't heard of a Panasonic Air Rad before. How does this work? Have looked online but not sure I am absolutely clear how they work. We have a similar problem to Jeremy in that the top floor of our house gets a little too warm and there is no way we can retrospectively fit a conventional air conditioner so we're looking at alternative cooling options. Link to comment Share on other sites More sharing options...
NSS Posted July 23, 2019 Author Share Posted July 23, 2019 It transpires that Panasonic don't 'encourage' the use of cooling to ufh systems without the installation of dew point sensors, so the system won't actually do so without some additional technical setup. Not entirely sure I understand all that might entail, but seems it will at least mean some changes to how the controller is connected to the heat pump. Of course, getting this done will a) not happen in the next 24 hours, and b) cost an unspecified sum of cash to be handed over. Given, that SageGlass has again done it's stuff today, keeping the indoor temperature bearable, my inclination is to keep said sum of cash in our bank account rather than someone else's for a while longer! Link to comment Share on other sites More sharing options...
ProDave Posted July 23, 2019 Share Posted July 23, 2019 What actually needs doing to it? Can you do it yourself? i.e can you just do it without sensors and keep an eye on it manually? Link to comment Share on other sites More sharing options...
NSS Posted July 23, 2019 Author Share Posted July 23, 2019 4 hours ago, JanetE said: @NSS haven't heard of a Panasonic Air Rad before. How does this work? Have looked online but not sure I am absolutely clear how they work. We have a similar problem to Jeremy in that the top floor of our house gets a little too warm and there is no way we can retrospectively fit a conventional air conditioner so we're looking at alternative cooling options. Hi Janet, it is part of the Panasonic Aquarea range and, as such, connects to a Panasonic Aquarea heat pump such as ours that has (in theory at least!) the ability to provide cooling as well as heat. If you don't have the correct ASHP, I doubt you could attach the air rad. 1 Link to comment Share on other sites More sharing options...
NSS Posted July 23, 2019 Author Share Posted July 23, 2019 2 minutes ago, ProDave said: What actually needs doing to it? Can you do it yourself? i.e can you just do it without sensors and keep an eye on it manually? Have convinced them I don't need the sensors, but it seems it would require the wiring from the controller to be terminated to different connections inside the heat pump (which is not something I'm going to attempt myself). Will give our friendly installer/maintainer a call later in the week ? Link to comment Share on other sites More sharing options...
Jeremy Harris Posted July 23, 2019 Share Posted July 23, 2019 I can understand their concern about the possible need for sensors, as it's conceivable that there could be a floor condensation problem if the floor got too cold and the humidity level was very high. I was worried about it when I first thought of switching our system to cool the floor, but realised after some experiments that the floor just doesn't get close to being cold enough to cause a condensation risk. I think the coldest I've ever measured at the floor surface is about 18°C, which is more than enough to cool the house a fair bit, but with a room temperature of 22°C would need a relative humidity of around 78% to pose a condensation risk. Today's been pretty humid, but the highest I've seen indoors was about 55%, and that's a fair bit higher than we normally see, it tends to sit around 40% to 45% much of the time. Hopefully your friendly installer can alter the wiring to get this working, as if it works as well as both ourselves and @jack have found it should definitely improve your comfort level on days like today (and, I suspect, the next couple of days). What tends to cause our house to get a bit too warm is a few consecutive hot days, without cool nights. It looks as if the temperature isn't going to dip below 20°C here tonight, and that, combined with much of the day being over 30°C, tends to build up the temperature in the fabric of the house, such that it will gradually get warmer with every additional hot day. Still, I've just checked and our bedroom is now sitting at 19°C, so I think we should be able to sleep OK. Pity we cannot just send "coolth" as an attachment to a post here to help others stay cool in this weather. Link to comment Share on other sites More sharing options...
NSS Posted July 23, 2019 Author Share Posted July 23, 2019 Humidity upstairs today was about 61% (we normally sit at between about 46 and 52) so again higher than is usual, but if we can deliver cool water to the floor at 15C (the pump is capable of going as low as 5C) then I don't see we'd have a dew problem either. As you say, hopefully they can sort it but at least we can cool the bedroom with the air rad in the meantime. Link to comment Share on other sites More sharing options...
Jeremy Harris Posted July 23, 2019 Share Posted July 23, 2019 1 minute ago, NSS said: Humidity upstairs today was about 61% (we normally sit at between about 46 and 52) so again higher than is usual, but if we can deliver cool water to the floor at 15C (the pump is capable of going as low as 5C) then I don't see we'd have a dew problem either. As you say, hopefully they can sort it but at least we can cool the bedroom with the air rad in the meantime. FWIW, if our ASHP pumps water at 12°C into the UFH, the surface of the slab never seems to get colder than 18°C, so at 15°C flow temperature I'd say you should have no condensation risk at all. 1 Link to comment Share on other sites More sharing options...
jack Posted July 23, 2019 Share Posted July 23, 2019 Just now, NSS said: Humidity upstairs today was about 61% (we normally sit at between about 46 and 52) so again higher than is usual, but if we can deliver cool water to the floor at 15C (the pump is capable of going as low as 5C) then I don't see we'd have a dew problem either. As you say, hopefully they can sort it but at least we can cool the bedroom with the air rad in the meantime. I run my supply temp at 15C. I get a breath of condensation on the manifold - never any droplets. I came in having been out for a bit this afternoon and it was like bloody heaven walking in the front door. Can't recommend it highly enough. 2 Link to comment Share on other sites More sharing options...
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