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Heat Pumps - post here.

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    #1442
    Shefwedfan
    Closed Accounts Posts: 18,958 ✭✭✭✭Shefwedfan


    H.E. Pennypacker wrote: »
    Can you find out the heat loss indicator from your BER assessor?

    As an easy test re the workability of a heat pump, get a pipe thermostat on your flow from the central heating. Turn it right down to 40C and see what the house feels like on a frosty night. Note that its not good for your boiler to have a return temp of less than 40C over longer periods.

    The SEAI grant might fund new radiators and a tiny bit of the heat pump if your HLI is ballpark (up to 2.3 as long as most works have been done and the rest are uneconomic). Interestingly (?), you can get the grant for a heat pump and retain your existing boiler as long as the heat pump and rads are specced to meet the heat requirements for the house.


    My current boiler will not switch down that low.....I checked that before


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    #1443
    Water John
    Registered Users Posts: 21,143 ✭✭✭✭Water John


    A mixer three way valve with a thermostatic head with thermostat clipped to the pipe can be rigged up to create a 40C feed to the rads.
    Shouldn't cost a lot. It simply circulates most of the water but adds a little from the boiler to keep the outgoing supply at 40C.
    Then you may not want to go fiddling.
    You'd also want to check the output of you present rads @ 40c v's aluminium rads.

    A more elaborate, but the same basic principle is used to connect a high heat source to UFH.


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    #1444
    H.E. Pennypacker
    Closed Accounts Posts: 844 ✭✭✭H.E. Pennypacker


    Shefwedfan wrote: »
    My current boiler will not switch down that low.....I checked that before

    What's your aim overall? If its saving money, then reducing your heat demand is more important than the heat source and that's where the money should go. If its environmental then a heat pump/oil boiler combo will reduce your oil burn but moneywise it won't be efficient. Note that Calahonda has pointed out that your nighttime consumption of electricity is reduced without UFH so your daytime consumption will be dirtier too.

    I've been through it and spent the money to get the house heat pump ready only to find that its much cheaper to stay with oil - my payback for a heat pump is something like 30 years as a result of my reduced oil usage. I like the idea of a heat pump for environmental reasons but I can't justify a cost instead of a payback as I have other financial responsibilities. IMHO, the current SEAI grant is inadequate for houses without UFH and will likely be increased within the next two years as the government comes under increasing financial pressure to reduce emissions.


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    #1445
    Water John
    Registered Users Posts: 21,143 ✭✭✭✭Water John


    It would need the addition of a large insulated storage tank to use a HP at night rate. If you had a private water supply you could also raise the efficiency by using a W2W HP.


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    #1446
    Shefwedfan
    Closed Accounts Posts: 18,958 ✭✭✭✭Shefwedfan


    H.E. Pennypacker wrote: »
    What's your aim overall? If its saving money, then reducing your heat demand is more important than the heat source and that's where the money should go. If its environmental then a heat pump/oil boiler combo will reduce your oil burn but moneywise it won't be efficient. Note that Calahonda has pointed out that your nighttime consumption of electricity is reduced without UFH so your daytime consumption will be dirtier too.

    I've been through it and spent the money to get the house heat pump ready only to find that its much cheaper to stay with oil - my payback for a heat pump is something like 30 years as a result of my reduced oil usage. I like the idea of a heat pump for environmental reasons but I can't justify a cost instead of a payback as I have other financial responsibilities. IMHO, the current SEAI grant is inadequate for houses without UFH and will likely be increased within the next two years as the government comes under increasing financial pressure to reduce emissions.

    I would not be using SEAI as when I checked the last time about it I was recommended off it as the cost to update the house would be too extremely. The windows/doors etc would have been installed in 2006 by previous owner and would probably not meet the requirement so would need to replace

    My main aim is really environmental while reducing requirements for oil, I have spent a small fortune on insulation’s and continue to upgrade as I go along but would like to update heating, A2W seemed the right direction but as I am in bungalow and heat recovery might also help


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    #1447
    H.E. Pennypacker
    Closed Accounts Posts: 844 ✭✭✭H.E. Pennypacker


    Shefwedfan wrote: »
    I would not be using SEAI as when I checked the last time about it I was recommended off it as the cost to update the house would be too extremely. The windows/doors etc would have been installed in 2006 by previous owner and would probably not meet the requirement so would need to replace

    My main aim is really environmental while reducing requirements for oil, I have spent a small fortune on insulation’s and continue to upgrade as I go along but would like to update heating, A2W seemed the right direction but as I am in bungalow and heat recovery might also help

    When I started the process I got a heat loss survey and air tightness test done. Its a really useful way of finding quick wins and makes for better future decisions. Heat recovery ventilation is relatively easy in a bungalow and makes for great air quality as well as relatively consistent humidity. If you have a reasonably sized room where your hot water cylinder and other plumbing lives, you can set up a dedicated drying room for clothes and you'll have another win on reduced dryer costs.


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    #1448
    ecowise
    Registered Users Posts: 125 ✭✭ecowise


    Cyrus wrote: »
    what vents would you suggest for more energy efficiency?

    i am in a similar position to the poster albeit we have been in the house over 2 years,

    its 195 sqm and A3 but to be fair electricity is running at 100 a month for a family of 4 so i cant complain (samsung heatpump)


    For passive vents check out Aereco and ICON also do anti-draught wall vents. I am sure there are others as well. We have whole house MHRV so I have not used them myself but Aireco have been in the market for a while. You could also talk to Aereco about their Demand Control Ventilation options. For active in-vent heat recovery Vent-Axia make small standalone units.


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    #1449
    ecowise
    Registered Users Posts: 125 ✭✭ecowise


    Just a follow up to a query I made back in August about our Genie heat pump. In the previous heating season it had cut out on 5 occasions and I was wondering if it was time to replace it (first installed in 2001). It turned out the HP was OK but the house circulation pump was faulty (seizing) and causing the HP to trip. I replaced the 245 watt Grundfoss circulation pump with a 40 watt Wilo and everything has been fine since. Hoping to get more years out of the Genie!


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    #1450
    crip123
    Registered Users Posts: 5 ✭crip123


    We just bought a 70's Bungalow , floor area is 130sqms , We're doing a full renovation with external insualtion and have gotten the builder to price up A2W vs an energy efficent boiler. The A2W heat pump is looking at 9.5k more (so 6k net after grant) . Anyone have any idea of the Payback? is it worth it?


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    #1451
    MENACE2010
    Registered Users Posts: 116 ✭✭MENACE2010


    crip123 wrote: »
    We just bought a 70's Bungalow , floor area is 130sqms , We're doing a full renovation with external insulation and have gotten the builder to price up A2W vs an energy efficient boiler. The A2W heat pump is looking at 9.5k more (so 6k net after grant) . Anyone have any idea of the Payback? is it worth it?


    Okay, to answer the question is it worth it. ( we have a house with A2W) after 8 years , for me a solid YES.



    We are living in a new build not a renovation and we have a comfortable house and hot water at any time of the day. No more oil deliveries and boilers that need to be bled because someone forgot to order oil. :D


    Flip side , instead of paying for oil you will be paying more for electricity for obvious reasons but you will not have a immersion or additional water heating going on that is on top of the boiler. How much more electricity I cannot give you the number ( my bill is now 170 euro per month in the winter with spread payment, my house is a lot larger so your bill could be lower)



    couple of recommendations, use triple glazing where you can .. and see if you can use heat recovery ventilation. In the winter this is something I only can recommend.

    I assume you are using the Radiators, use a smart thermostats in the room to control heat that will control how much the heating will kick in.


    check with the ESB for night rate meter and night rate, we produce all our hot water at night at lower rate ( we run dishwasher after 11PM as well) . We have a Xtra large hot Water tank (300Liter) so that covers easily 4 people or more depending on shower time. :p
    Our tank loses a 1C per 24 hours, so when the heating is off and the A2W only produces hot water the frequency of running comes down a lot = lower cost as in the summer the A2W gets far more effiecient with generating hotwater ( The colder the weather the less efficient the A2W gets but the newer A2W are pretty good )



    For me it was a no brainer, with the trend everything going away from fossil fuels i can only imagine that the boilers are going to be next on the chopping block


    Good luck with the house , DM me if you need more info or contacts


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    #1452
    Mr Q
    Registered Users Posts: 993 ✭✭✭Mr Q


    crip123 wrote: »
    We just bought a 70's Bungalow , floor area is 130sqms , We're doing a full renovation with external insualtion and have gotten the builder to price up A2W vs an energy efficent boiler. The A2W heat pump is looking at 9.5k more (so 6k net after grant) . Anyone have any idea of the Payback? is it worth it?

    An additional 9.5k seems very expensive over a boiler. Probably worth getting a few more prices on that section of the job.

    I have one installed and would say it is well worth it. For heating and hot water it used 700 kWh of electricity for December and January just gone. I had a meter put in for this to track the usage.

    From what MENACE2010 said about losing only 1 degree per day I assume he has a seperate DHW tank. Mine is built into the indoor unit and loses a huge amount of heat over 24 hours compared to what he has described. His set up sounds much better in this regard.


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    #1453
    MENACE2010
    Registered Users Posts: 116 ✭✭MENACE2010


    Mr Q wrote: »
    An additional 9.5k seems very expensive over a boiler. Probably worth getting a few more prices on that section of the job.

    I have one installed and would say it is well worth it. For heating and hot water it used 700 kWh of electricity for December and January just gone. I had a meter put in for this to track the usage.

    From what MENACE2010 said about losing only 1 degree per day I assume he has a seperate DHW tank. Mine is built into the indoor unit and loses a huge amount of heat over 24 hours compared to what he has described. His set up sounds much better in this regard.


    correct its a separate tank Dimplex ECO ECS300HP
    ps. We have a closed water suppy, no longer 300 liter tank on the attic..


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    #1454
    Mr Q
    Registered Users Posts: 993 ✭✭✭Mr Q


    MENACE2010 wrote: »
    correct its a separate tank Dimplex ECO ECS300HP
    ps. We have a closed water suppy, no longer 300 liter tank on the attic..

    That looks really well insulated, not surprised you're only losing only 1 degree per day.

    If i had a choice I would go for that every time over the indoor unit I have with integrated tank. The insulation level is poor by modern standards but it is a packaging compromise to get everything into a 600mm by 600mm unit I assume.


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    #1455
    John.G
    Registered Users Posts: 3,468 ✭✭✭John.G


    That 1 degree per day may be a bit optimistic, I think that dimplex 300 litre unit claims 1.96kw/24 hr loss which equates (my calcs) to 5.62C/24hr loss or 0.23C/hr, still excellent.


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    #1456
    ToxicPaddy
    Moderators, Business & Finance Moderators, Society & Culture Moderators Posts: 9,764 Mod ✭✭✭✭ToxicPaddy


    If anyone could help me here, I'd be very appreciative.

    We moved into a new build late last year with a Dimplex A Class heat pump and so far it's not been a positive experience. The house is pretty much perfect except for the heating system issues and all this over a fairly cold miserable wet winter which hasn't helped.

    In 4 months we have been in we had a few minor issues and one major issue which has seen the heating system stop working completely and the internal temp of the house drop to 14C, this weekend the second is occurring, again the heating system appears to have completely stopped and its currently at 17c inside but getting colder by the hour.

    The first time, after a week of chasing the installers, they eventually arrived and really didn't seem too sure what they were doing. It's like it was the first time they actually saw a system like this and it didn't inspire confidence watching them work. They supposedly fixed the system but it hasn't been 100% since then. I've called and called but to no available, the only contact with them being a bill for something that should have been covered under warranty.

    Then to add to it all, our last electricity bill was for €430, definitely not expected and not inspiring confidence in how efficient this system is meant to be.

    Due to our experience with the original installers I really don't want to have to deal with them again as I know I'll spend weeks chasing them only to have the same result.

    I heard so many positive things about these heating systems that I had high hopes but at this stage I've pretty much lost all faith in them.

    If anyone can recommend a decent knowledgeable company around Dublin who know the Dimplex A Class systems, I'd happily pay them to come and try to sort this issue.

    What I would like is for them to give the whole system a complete inspection, a full service and review it from top to bottom. Then to go through a few details with me to make a sure I'm not doing anything stupid.

    I honestly believe that this system hasn't been configured correctly from the start and it could be a glimpse of what's to come, so I'd like a second opinion so to speak from someone who actually knows what they are doing.

    I have found a few in the area but I would like personal recommendations rather than rolling the dice and ending up with the same experience again.

    Thanks.


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    #1457
    MENACE2010
    Registered Users Posts: 116 ✭✭MENACE2010


    Hi
    Sorry to hear its not working out, I'm at the westcoast but so I cannot recommend a particulair installer for you, the company that installed /designed mine is ashgrove in dublin I would give them a call and they could give you a steer in the right direction.

    contact Dimplex if you have not done so maybe they can assist as well .

    Things to check ..
    - Alarms on the control panel ?
    - thermostats , set them as high as possible, check water flow at manifold (assuming you have underfloor heating), if you have rads check for air in the rads (try to bleed them)
    - do you have hotwater , if so heatpump is functioning or using the imersion

    Download the installers manual ( get a pot of tea / coffee and read through the installers and user manual end to end) , if you follow it correctly you can check it yourself ( if your comfortable enough with it)


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    #1458
    Calahonda52
    Registered Users Posts: 12,221 ✭✭✭✭Calahonda52


    Any other houses in the estate with the same issues?
    find out who did the install and IIRC, the new Building controls system should enable you to find out who signed off on the design.
    As advised earlier, get the serial number off the unit and contact dimplex, they have a reputational risk issue here to manage.
    The unit may be a fake, there is growing evidence of "plumbers" buying kit directly from websites...... so if "plumbers" do it builders may also
    The user manual should have been left in the house

    “I can’t pay my staff or mortgage with instagram likes”.



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    #1459
    Kash
    Registered Users Posts: 1,065 ✭✭✭Kash


    We have a 4 bedroom bungalow, built in the 70s. We are investigating installing a heat pump to replace/supplement our solid fuel stove. We had a SEAI registered assessor compete a technical assessment of the house, and he has given us a list of improvements - including installing UFH and replacing most of the windows and doors.

    He gave me a ballpark estimate of the improvements coming to €50-60k which we simply cannot afford.

    Is our dream of a warm house over?


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    #1460
    Water John
    Registered Users Posts: 21,143 ✭✭✭✭Water John


    Sealing and insulating the house are the two key essentials. The floor isn't the greatest loss of heat, but the most difficult to fix. To put in UFH means digging down 12-15 inches and putting in a sub floor and then 6 inches of insulation.
    If you can avoid all that, the house won't be perfect but will be reasonably warm.
    If you wanted to go HP then you could use aluminium rads.
    Can the engineer give you a second BER calculation based on that? That won't take him 5 mins as he has the house entered on the software already.

    Know an elderly relation who has a sort of prefab concrete house from the 1970s. He went with exsulation and it made a big improvement.


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    #1461
    MENACE2010
    Registered Users Posts: 116 ✭✭MENACE2010


    Kash wrote: »
    We have a 4 bedroom bungalow, built in the 70s. We are investigating installing a heat pump to replace/supplement our solid fuel stove. We had a SEAI registered assessor compete a technical assessment of the house, and he has given us a list of improvements - including installing UFH and replacing most of the windows and doors.

    He gave me a ballpark estimate of the improvements coming to €50-60k which we simply cannot afford.

    Is our dream of a warm house over?




    Hi, I don't think the dream is over. The assessor was a good start, the recommendations are what you would do in a perfect "money is no object" kinda situation.



    The main aim is not to lose heat , once you can achieve that it does not really matter what the heating system is.



    Window replacement - is a good start if they are old, cold, leaky and condensation is running off the glass on the inside. Shop around and ask for a quotations. Price varies significantly . If possible use triple glazing or double with a very good U value.



    House insulation - equally a good start, pump cavity or use external insulation. Check the attic space where you are prone to lose significant amount of heat. Insulate the floor of the attic space if possible. Google , shop around ask questions .. :)



    Ventilation - Air-tightness .. find the droughts and fix them, now if you have those lovely "holes in the wall " for ventilation , google for Heat recovery options for existing dwellings .. get advise what holes to can close up .



    Stove replacement - if you have an open fire at the moment , get a stove and potentially a stove with an external fresh air feed from the outside. Most of the heat of the house leaves through the Chimney on older buildings.



    HeatPump is nice but you need to ensure first that you don't or minimize the loss of heat otherwise it will get expensive very quickly. Get a new boiler is probably better in the long run ( condensing boiler) and equip rads with Thermostatic valves so they close and open on a set temperature.



    Overall , split all this in smaller projects , check what grants you are entitled to use the grants for the big stuff and save for the smaller project bits (stove, rads )


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    #1462
    antoinolachtnai
    Registered Users Posts: 9,774 ✭✭✭antoinolachtnai


    The above is excellent advice.

    There is another way to look at it though. Your house needs a major refurb at some stage in the next twenty years. Rather than doing lots of items one by one you might be better doing the essential things now but deferring any major project for five or ten years and saving toward it in the interim. At that point make a large investment in a full retrofit and refurb of the house.

    These are just ways of looking at it. The best option for you may lie somewhere in between the extremes.


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    #1463
    Calahonda52
    Registered Users Posts: 12,221 ✭✭✭✭Calahonda52


    https://www.nsai.ie/about/news/publication-of-sr-542014-code-of-practice
    Good advice above,
    some of the actions may delivery good airtightness so the work needs to be sequenced.
    Starting point must be uncontrolled ventilation.
    If doing windows then do them and EWI at same time , hanging the new windows on the outside, minimises thermal bridging.
    What are the existing floors, if concrete then UFH will be a world of hurt
    If timber and you intend to pour concrete then more hurt.

    Its all doable but for the UFH etc you will need to move out: how practical is that?

    “I can’t pay my staff or mortgage with instagram likes”.



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    #1464
    ToxicPaddy
    Moderators, Business & Finance Moderators, Society & Culture Moderators Posts: 9,764 Mod ✭✭✭✭ToxicPaddy


    Thanks for the replies guys, the installers came back, said it was something they couldn't fix, gave me a list of error codes and referred me to Dimplex.

    I've called Dimplex, gave them the info and informed me that it's a possible PCB failure but the system is under warranty for parts and labour so would have someone out on Monday (this was on Friday afternoon so reasonable to exoect). They would call me back then to confirm a time the engineer would call out st. No call by lunchtime so I called after lunch, they said they would call me back immediately, no call back so 10 days after initial report of fault, still no resolution in sight.

    Getting a bit fed up with this a now and I've had to resort to buying some small fan heaters for the house as its too cold on the ground floor to spend any time there.


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    #1465
    Water John
    Registered Users Posts: 21,143 ✭✭✭✭Water John


    If my memory is correct, the local installer of Dimplex installs but activation, which cost something like €500 was done by Dimplex themselves. Stand to be corrected on this. But if that's the case, I would expect both phone support and attendance within 24 hours.


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    #1466
    NonPlussedNW
    Registered Users Posts: 6 ✭NonPlussedNW


    I bought a recently completed house last October that has an Air to Water HP with UFH. I don’t think it is working as well as it should, but the installer insists all is well. I’m hoping someone with more experience of this type of setup can advise.

    The house is rural, detached, 245sqm, well insulated (bead-filled cavity and dry-lined walls, triple glazing), A-rated but not passive. It seems to hold the heat well.

    HP system is a Panasonic 12kw mono-block with a 70 litre heating buffer tank built in to the DHW tank. It is set for a heating water temperature of 37c. UFH has 10 zones with individual room stats.


    First issue is that the system reports low COP values. Monthly averages for the first 4 months of this year were: 2.2, 1.6, 1.3, 1.4. So far this month it is 1.3.
    I understand this can possibly arise from a mis-calibrated sensor causing a miscalculation of the COP, rather than an actual underlying problem, but is there any way to gauge for myself the actual efficiency level? I presume most installations manage to show reasonably accurate COP values, otherwise why have the display?


    Second, I suspect the system isn’t pushing the heat round the system fast enough. I’ve been monitoring the temperatures in one 15sqm room, north facing so minimal solar gain. The heating system can run for 1.5 hours just to maintain this one room at set-point, raising the room temperature by half a degree. During this time the HP runs in cycles of approx 6-7mins on, 11mins off waiting for the buffer to cool. UFH systems respond slowly, but is this excessive?

    The floor in this room is heated unevenly. Maximum floor tile surface temperature increase can be 3 degrees on one edge of the room, but barely one degree on the other. The return pipe at the manifold has almost no noticeable heat, even after running for over an hour. It seems like the heat is being circulated at too low a rate. With the valve wide open, the indicator shows 1 litre per minute flow on the loop, which I thought was a typical value but doesn’t seem sufficient. The circulation pump is a Grundfos in UFH mode on the lowest speed setting.

    Initially there were multiple actuator valves stuck permanently open, which was corrected in February. This coincided with a significant drop in the reported COP. This would seem to confirm that the heat distribution is a bottleneck – the HP appeared to run more efficiently when the heat was always pumping to multiple rooms.


    Third, the energy usage seems higher than expected. According to the electricity meter, total consumption has averaged about 690 units per month October-April. Internal finishing work continued through much of this time, so the house wasn’t full time occupied and had no other heavy energy consumers such as electric oven or dishwasher. HP would account for most of the electricity consumed, and this seems to tie in with the consumption reported by the HP itself.

    With so many variables, I’ve found it is difficult to find any definitive information on what a reasonable consumption level should be. If the installer comes back, ups the pump speed and declares it fixed, how can I independently confirm that the system is actually running efficiently, especially when heating demand is much reduced in the warmer weather?

    Are there any other potential causes that I should investigate?


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    #1467
    John.G
    Registered Users Posts: 3,468 ✭✭✭John.G


    You may be able to take a few readings with no hot water (demand) draw off, do you know what the 70 litre cutin/cutout temperatures are, if you do then it is a very easy to calc the energy required to bring it back up to temperature and if you can obtain elec meter readings for this period then the cop can be calculated, if you are taking the meter readings from the main "ESB" meter then ensure that there are no other large users on for this fairly brief period. Also, as I see you have a HP consumption meter, obviously note this as well.


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    #1468
    MENACE2010
    Registered Users Posts: 116 ✭✭MENACE2010


    NonPlussedNW wrote: »
    I bought a recently completed house last October that has an Air to Water HP with UFH. I don’t think it is working as well as it should, but the installer insists all is well. I’m hoping someone with more experience of this type of setup can advise.

    The house is rural, detached, 245sqm, well insulated (bead-filled cavity and dry-lined walls, triple glazing), A-rated but not passive. It seems to hold the heat well.

    HP system is a Panasonic 12kw mono-block with a 70 litre heating buffer tank built in to the DHW tank. It is set for a heating water temperature of 37c. UFH has 10 zones with individual room stats.


    First issue is that the system reports low COP values. Monthly averages for the first 4 months of this year were: 2.2, 1.6, 1.3, 1.4. So far this month it is 1.3.
    I understand this can possibly arise from a mis-calibrated sensor causing a miscalculation of the COP, rather than an actual underlying problem, but is there any way to gauge for myself the actual efficiency level? I presume most installations manage to show reasonably accurate COP values, otherwise why have the display?

    not all systems have a COP display ( have not seen it on mine) lower COP is A. based on the outside temp and potentially a misconfigured / badly placed sensor


    Second, I suspect the system isn’t pushing the heat round the system fast enough. I’ve been monitoring the temperatures in one 15sqm room, north facing so minimal solar gain. The heating system can run for 1.5 hours just to maintain this one room at set-point, raising the room temperature by half a degree. During this time the HP runs in cycles of approx 6-7mins on, 11mins off waiting for the buffer to cool. UFH systems respond slowly, but is this excessive?

    okay, check your manifold it could be valves are not opening correctly or not enough for the water to circulate, there could even be trapped air in the pipes, see if you can bleed the system

    The floor in this room is heated unevenly. Maximum floor tile surface temperature increase can be 3 degrees on one edge of the room, but barely one degree on the other. The return pipe at the manifold has almost no noticeable heat, even after running for over an hour. It seems like the heat is being circulated at too low a rate. With the valve wide open, the indicator shows 1 litre per minute flow on the loop, which I thought was a typical value but doesn’t seem sufficient. The circulation pump is a Grundfos in UFH mode on the lowest speed setting.

    uneven heating is loops under tiles not looped in a consistent manner not a whole lot you can do there

    Initially there were multiple actuator valves stuck permanently open, which was corrected in February. This coincided with a significant drop in the reported COP. This would seem to confirm that the heat distribution is a bottleneck – the HP appeared to run more efficiently when the heat was always pumping to multiple rooms.

    Check and Check again, it true the pumps work better with open flow, I stopped using my thermostats and use the Heatcurve setting on the HP to control the room temperature

    Third, the energy usage seems higher than expected. According to the electricity meter, total consumption has averaged about 690 units per month October-April. Internal finishing work continued through much of this time, so the house wasn’t full time occupied and had no other heavy energy consumers such as electric oven or dishwasher. HP would account for most of the electricity consumed, and this seems to tie in with the consumption reported by the HP itself.

    YUP welcome to the party, the power consumption can be high especially if its cold, ( less efficiency) the heatpump has to work harder with a lower outside temp = higher electricity costs

    With so many variables, I’ve found it is difficult to find any definitive information on what a reasonable consumption level should be. If the installer comes back, ups the pump speed and declares it fixed, how can I independently confirm that the system is actually running efficiently, especially when heating demand is much reduced in the warmer weather?

    Are there any other potential causes that I should investigate?

    okay, there are a couple of points in your text that potentially could be causes for some extra attention

    - check if there is no airlock in the UFH loops
    - check if the attenuators are working correctly
    - check if the sensors are working correct and display the correct temp
    - Water pressure correct in the system (I presume so , but I had an installation error on my install.. the top up valve was left open and the system had overpressure all the time ..only when I closed that valve it was correct ) ?

    So there is no "golden Rule" or comparison, I spend 170 euro a month with Airtricity on a spread payment contract, this is everything cooking /heating /working from home /hotwater. At the moment my heating is off and the HP only makes hotwater ( Elec.bill is now lower) but I have to pay for the differential


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    #1469
    Water John
    Registered Users Posts: 21,143 ✭✭✭✭Water John


    A while since involved in the trade but my memory is of 1.5l/min flow on each loop. The 15 sq m room should be one loop of about 100 metres (the max for a loop) at 150mm spacing. Water in might need to be at 40C to UFH.

    If trades were working, doors in and out would be opening quite a bit.
    If HW is at 70C that is high and would burn electricity to get there. (Misread the 70l tank there but check that the HW temp isn't too high.)
    Are all the loops controlled by stats, one would really need to be an open circuit, so the water pump isn't hammering when all circuits close.


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    #1470
    MENACE2010
    Registered Users Posts: 116 ✭✭MENACE2010


    Water John wrote: »
    A while since involved in the trade but my memory is of 1.5l/min flow on each loop. The 15 sq m room should be one loop of about 100 metres (the max for a loop) at 150mm spacing. Water in might need to be at 40C to UFH.

    If trades were working, doors in and out would be opening quite a bit.
    If HW is at 70C that is high and would burn electricity to get there. (Misread the 70l tank there but check that the HW temp isn't too high.)
    Are all the loops controlled by stats, one would really need to be an open circuit, so the water pump isn't hammering en all circuits close.

    I concur with the above, google for installation & planning manual <followed by the type and model of heatpump> and read that through so you have an understanding of why /how and what.

    my tap water is 46C ... but the HP has an anti legionairs disease system once every couple days it fires the temperature up to 70C to kill whatever might lurk in the pipes and tank.

    https://www.panasonicproclub.com/uploads/BE/catalogues/A2W_2018_DesignManual.pdf


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    #1471
    Calahonda52
    Registered Users Posts: 12,221 ✭✭✭✭Calahonda52


    Put a sub meter on the HP so as you know exactly what it is pulling.
    Is your weather compensation control located properly and working properly
    From what remember in a recent training course, 10 individual zones on a UFH set up is not good design

    “I can’t pay my staff or mortgage with instagram likes”.



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