Your browser isn't supported
It looks like you're using an old web browser. To get the most out of the site and to ensure guides display correctly, we suggest upgrading your browser now. Download the latest:

Welcome to the MSE Forums

We're home to a fantastic community of MoneySavers but anyone can post. Please exercise caution & report spam, illegal, offensive or libellous posts/messages: click "report" or email forumteam@.

Search
  • FIRST POST
    • richardc1983
    • By richardc1983 4th Feb 09, 2:03 AM
    • 1,999Posts
    • 1,038Thanks
    richardc1983
    Air to Air Heat Pumps/Air Con - Full Info & Guide
    • #1
    • 4th Feb 09, 2:03 AM
    Air to Air Heat Pumps/Air Con - Full Info & Guide 4th Feb 09 at 2:03 AM
    With all the posts ongoing here regarding heat pumps etc I have decided to start a new post I have put together with information on reverse cycle air conditioning (heat pumps), where people can ask questions, chat about heat pumps, discuss experiences, installs, electricity usage & anything else heat pumps related.
    Theres a lot of info here to take in, please do read it all as this may just


    How does it work?

    It's actually quite simple. Air conditioners work in much the same way as your refrigerator except there are two separate, but integral, parts to the system. There is an outside unit housing the compressor that is similar to the exterior back of your fridge. It draws warmth from the outside air in even the coldest of weather. That warmth is then transferred inside the home using a refrigerant process through a piping system powered by an indoor fan unit that is typically mounted to the wall. This is why the system is also often referred to as a heat pump rather then air conditioning. Both are in fact the same. Similarly, in summer, the reverse happens. Warm air is drawn from the interior room and expelled by the outside unit.

    Heat Pumps are capable of transferring up to 4kW of heat into a space while only consuming 1kW of electrical energy. The energy efficiency of a heat pump will decreases as the temperature difference between inside and outside becomes greater, even at low temperatures a heat pump can provide 3 times as much heat as a normal electric space heater would provide with the same amount of electricity input. This makes Heat pumps extremely energy efficient.

    "Not all Heat Pumps are designed to continue working where temperatures fall below freezing point"

    The principle of air conditioning always comes down to the same:

    absorb energy in one place and release it in another place

    The process requires an indoor unit, an outdoor unit and copper piping to connect both. Through the piping the refrigerant flows from one unit to another. It is the refrigerant that absorbs the energy in one unit and releases it in the other.
    Cooling mode (Heating mode is the same but in reverse)

    1 Indoor unit
    A fan blows the hot indoor air over a heat exchanging coil through which cold refrigerant flows. The cold refrigerant absorbs the heat from the air and cooled air is blown into the room.
    2 Copper piping
    The refrigerant circulates through the units and the piping and takes the heat from the indoor unit to the outdoor unit.
    3 Outdoor unit
    Through compression, the refrigerant gas is heated and its boiling point increases. In the outdoor unit the obtained heat throught compression is released to the outdoor air by means of a fan which blows the outdoor air over a heat exchanging coil.
    4 Refrigerant
    The liquid refrigerant flows back to the indoor unit.
    5 Indoor unit
    Back in the indoor unit, the refrigerant is decompressed and thus enabled to extract heat form the indoor air.



    Comparison of 2400w fan heater & Heat Pump Running Costs:

    http://www.bdt.co.nz/comfortmaster/data/guides/WinterRunningCostsComparison.pdf - this is for Mitsubishi Electric but savings made on other manufacters however these will vary.

    Inverter Technology:

    Here's some info about inverters, the same applies across all manufacturers however efficiency levels are different but the operation side of things is the same. There is an article at the bottom from Mitsubishi Electric where they have done a comparison test for a fan heater and heat pump. This is not unique to Mitsubishi Electric, similar costs will be seen across all heat pumps... its a very efficient technology. Different manufacturers will have different efficiencies. The best manufacturers are Mitsubishi Electric, Daikin, Mitsubishi Heavy Industries, Fujitsu, Sanyo, LG, any other manufactures are entry level and will not offer as good quality systems or efficiencies.

    Inverter systems save energy by using a variable controlled Compressor. The output is controlled to only provide the energy required to keep the room to the set temperature. By reducing the output required less power is used and this substantially reduces power consumption. Inverter control not only saves you money but also keeps you more comfortable.


    Inverter System or Fixed Speed System?

    What is a Fixed Speed Split System?

    This system only has a single speed compressor motor that is either on or off.

    It works similar to a fan heater that switches off when the desired temperature is reached and on again when the temperature drops to a set level. It speeds up or slows down to calculate the heat loss from the space to be heated ensuring it is only putting in the same amount of heat that the space is losing.

    What does Inverter Mean?

    Inverter technology uses a variable speed compressor motor similar to a car. It simply slows down and speeds up as needed to hold a selected comfort setting.

    Inverter technology provides a more precise room temperature without the temperature fluctuations of fixed speed systems.

    Inverter vs Fixed Speed:

    Inverter Systems are Approximately 30% more efficient than fixed speed systems.

    Inverter systems reach desired room temperature quicker.

    The speed control of the outdoor unit also means quieter operation, this is important especially at night in residential areas.









    Inverter Systems
    • Increased output to achieve set temperature faster.
    • Then varies the output to maintain a constant room temperature.








    Fixed Speed Type
    • Slowly gets to temperature as output rating is fixed.
    • Then turns on and off to maintain room temperature.
    Sizing of units:

    Read the following guide for sizing info: Excuse the references to Australia and New Zealand this contains useful info:

    http://www.bdt.co.nz/comfortmaster/data/guides/heatpump_sizing_quideline.pdf


    What type of unit is best suited for your property:

    Heat Pumps / Air Conditioners are manufactured with various indoor unit options. High Wall Type, Ceiling Cassette Type, Floor Mounted Type, Concealed Ducted Type, and Under Ceiling Type.


    High Wall-mounted

    The most popular residential unit choice. These units tend to be the quietest as well as taking up no floor space.

    Compact Floor Console

    The floor mounted are more designed for heating applications. They are ideal for space heater or gas fire/fireplace replacement. They can be recess mounted into the wall cavity giving a shallow profile for hallway installation.

    Ceiling Cassette

    The ceiling mounted units take up no floor space. These units have four way air direction and have adjustable air flow patterns. These units are more suited to larger floor areas & commercial properties.

    Ceiling Concealed (Ducted)

    These units are mounted in the ceiling space and are unseen in the conditioned space. The only visible presence is the supply and return air grilles.

    Ceiling Suspended

    These units are more suited to high stud large room areas. They tend to have high airflows and are more suited to commercial applications.

    Multi-Split Systems








    Multiple Indoor Units can be Connected to a Single Outdoor
    • Connect from 2 to 8 Indoor Units
    • Many Combination Patterns to choose
    • Energy Saving and Quiet Operation
    • Five Multi-Split Systems from 6.4kW to 16.0kW (Heating)
    Inverter Multi-Split system models are designed to allow several indoor units (regardless of capacity or type) to be connected to a single outdoor unit. This allows you to select the model best suited to each and every room in your property.


    Example: 3x Bedrooms and 1x Office

    ~


    Location of units:

    Indoors:

    Don’t locate units with obstructions in front.

    Result:


    Short cycling of air back to units room sensor making the unit think its wamer/cooler than it actually is.
    Air is not circulated correctly leaving cold/hot areas in room.

    Try to locate the indoor unit where the airflow is pointing to the other areas of the house that may require residual heating/cooling.

    Outdoors:

    Avoid paved areas unless a drain kit is fitted. Result: Units condensate and drip water. May cause slime build up or ice. If no other place please advise customer.

    Noise:
    Outdoor inverter units are very quiet and have scroll compressors, watch the following video and you will see mine in action:
    http://www.youtube.com/watch?v=-mUzYHEfQEY


    Defrost Cycles & Correct Sizing of Outdoor Unit:
    Defrost will happen in all climates, however the lower the humidity the less frequent it will defrost as it takes longer for it to build up on the outdoor coil.

    You will probably not even notice it defrosting, if you buy a decent brand system you will find that the defrost strategy is very good so that it doesn’t take long to defrost.

    When they defrost you will find that the system goes into reverse, taking heat from the inside circuit to the outdoor unit so it defrosts. This will last about 5 minutes depending on how much ice has built up but you have to look at the unit to notice it doing it as it doesn’t start making things cold inside. The unit just doesn’t heat during that time.

    Some units in New Zealand or other countries that have very cold winters have units optimised for that country, i.e. defrost cycles instead of stopping and going into reverse will inject hot gas into the outdoor unit whilst the unit is heating so that it doesn’t actually stop heating. Currently can only find info on Sanyo air to air heat pumps in this country that do this... not sure of a system that does this on a unit that will provide this on hot water but you can see the technology is there. As I say you don’t need it in the UK climate our winters are not as harsh as some countries.

    The best method for new builds is under floor heating, nice even temps throughout, however longer warm up times due to the lower water temperature but if left on during cold weather you will be fine.

    I personally prefer fan coil units as these double up as cooling/ac for the summer and provide very fast warm up times.

    Most air to water outdoor units can be used with fan coil units... you just use a fan coil instead of a water coil in the floor.

    Mounting of unit... must be installed in the open, no enclosure, so no garages, lofts or corners the unit must be in the open air.

    A user in another post:

    http://forums.moneysavingexpert.com/showthread.html?p=29040015#post29040015

    He installed it in the loft and it froze the loft in the cold weather and thawed and caused leaks into the house below, this happened twice and after this he decided to mount the unit outside and it performed better as it was effectively turning the loft into a giant fridge/freezer.

    Here’s some more info on heat pumps:



    Defrost Strategy

    When the outside temperature drops below zero all heat pumps must perform a “defrost cycle” to remove ice build up on their outdoor coils.

    Defrost strategy is determined by individual Heat Pump manufacturers. These strategies vary greatly between brands. Older style Heat Pumps initiated defrost by a fixed time or coil temperature. This system was not efficient as it often caused Heat Pumps to defrost too often or effected performance by not defrosting often enough. Defrost cycle is required when the outdoor coil is too cold or covered in ice preventing heat transfer and unit performance.

    All Heat Pumps must defrost. heats pumps utilise a Fuzzy Logic software program, a form of Artificial Intelligence contained in the chip of the outdoor unit and typically lasts between 3 to 5 minutes.

    The program measures and records:

    - Ambient Temperature
    - Outdoor Coil Temperature
    - Accumulated Continuous Heating Running Times
    - Defrost Initiation Time and Termination Times

    The program optimises this data based on history to produce defrost initiation only when absolutely required.

    This is important as Heat Pumps are unable to produce heat when they are in defrost mode. This is extremely important to real performance in low ambient conditions.

    Defrost Cycle Management

    Heat Pumps optimise its defrost cycle once selected in three ways:
    When the outside temperature drops below zero all heat pumps must perform a “defrost cycle” to remove ice build up on their outdoor coils.

    Defrost strategy is determined by individual Heat Pump manufacturers. These strategies vary greatly between brands. Older style Heat Pumps initiated defrost by a fixed time or coil temperature. This system was not efficient as it often caused Heat Pumps to defrost too often or effected performance by not defrosting often enough. Defrost cycle is required when the outdoor coil is too cold or covered in ice preventing heat transfer and unit performance.

    The program measures and records:

    - Ambient Temperature
    - Outdoor Coil Temperature
    - Accumulated Continuous Heating Running Times
    - Defrost Initiation Time and Termination Times

    The program optimises this data based on history to produce defrost initiation only when absolutely required.

    This is important as Heat Pumps are unable to produce heat when they are in defrost mode. This is extremely important to real performance in low ambient conditions.



    1. Compressor Control
    When a Heat Pump is defrosting it is not providing heat to the controlled space. It runs the compressor(inverter drive) at maximum speed during defrost to bring the outdoor coil up to temperature as quickly as possible. This melts any ice formed on the coil fins quickly and minimises defrost time. Minimising defrost time maximises heat output per hour real time.

    2. Dry Coil Defrost Cycle
    Once the outdoor coil is up to temperature and the compressor cycle has completed there is generally water between the outside coil fins. If the outdoor unit were to immediately resume heating the outdoor coil would freeze and prevent heat exchange. To prevent this the outdoor fan is run at maximum speed prior to resumption of the heating cycle. This is often characterized by steam blowing from the outdoor unit. This ensures the coil is completely dry before the heating cycle resumes.

    3. Time optimization through Fuzzy Logic
    Time between defrost cycles is continually being reviewed and optimized by the Heat Pump microprocessor software. Algorithmic calculations based on previous history is used to calculate the next defrost period.

    Fuzzy Logic or learning logic is a form of artificial intelligence. Defrost cycle termination is based on a combination of time and temperature. These parameters are used to calculate the next defrost period.

    Outdoor Humidity
    Outdoor humidity also effects heating performance. Areas that have a “dry cold” or low humidity such as “Mount Cook” will perform better at low ambient than say Taupo where ambient conditions can reach zero and “misty” moisture laden air conditions exists. The more moisture in the air the more moisture will freeze on the outdoor coil.

    Incorrect Unit Selection
    If a unit is selected that is too small the Heat Pump will run continuously and never reach set point. This continuous running will increase defrost requirements by reducing the outdoor coil running temperature and driving it into sub zero temperatures for excessive periods. The unit will defrost at the minimum intervals and may never catch up and achieve set point.

    Location of Outdoor Unit
    Location of the outdoor unit is essential for low ambient performance. Units located under houses, decking and in areas where airflow is impeded may create their own microclimate (i.e. giant fridge/freezer or in summer oven) and reduce the effective outdoor ambient temperature that the units operates in. Locating the outdoor unit too close to a wall and not observing clearances will also prevent the unit from delivering full output.


    Get the correct sized unit:
    Choosing the right sized Heat Pump is key to ensuring optimum comfort levels. Every home is as individual as its owner. The key to selecting the right Heat Pump for heating your home is choosing the correct unit size. Choosing the wrong size can cost you more in power consumption.


    Insulation and building orientation are key aspects in terms of potential heat loss a home is effected by. An older style home with poor insulation will lose indoor heat much quicker than a modern well insulated home that faces north.
    The quicker a home loses its heat, the bigger the Heat Pump system will need to overcome this heat loss.
    Last edited by richardc1983; 03-01-2011 at 4:00 PM.
Page 90
    • zeupater
    • By zeupater 23rd Jul 19, 6:10 PM
    • 4,975 Posts
    • 6,733 Thanks
    zeupater
    You appear to be assuming that the System COP of fredwnelson's ASHP is well over 3.0. If you look at the any of the independant trials of ASHPs only a few achieve a COP of 3.0.


    The requirement for an ASHP to run 24/7, or at least very long hours, means it compares unfavourably with conventional gas/oil CH systems in terms of overall heat requirement.

    Most people with gas/oil CH shut off, or turn down the thermostat, overnight or when they are out during the day. With the high water temperature available it will quickly bring the house up to the required temperature.

    The low water temperature of an ASHP means it has to run much longer hours producing heat that is not required at night or when occupants are out during the day.
    Originally posted by Cardew
    Hi

    If the HP is being run with UFH and at low temperatures then there's no real reason why it couldn't achieve a COP of 3.0 or more, most of the issues I've seen seem to be linked to running the system on a heating pattern similar to that you mention as if it were a much larger capacity GCH system and therefore reducing overall efficiencies ....

    Regarding the heating at night .... you may have noted that the issue is that the question revolves around the system being able to consume low tariff energy, which may mean that the OP wants to do that very thing ... charging up the thermal mass of the property overnight and effectively using the structure as a storage heater throughout the day .... this is essentially the reverse of what we do for much of the year in using PV generation to run the HP to 'charge up' the thermal mass during the day and have little/no need for heat provision overnight! ...

    HTH
    Z
    "We are what we repeatedly do, excellence then is not an act, but a habit. " ...... Aristotle
    • Cardew
    • By Cardew 24th Jul 19, 11:02 AM
    • 28,030 Posts
    • 13,881 Thanks
    Cardew
    Thanks. Not sure where the 20000kwh derives.
    Originally posted by fredwnelson

    The 'performance' of a heat pump is measured by its COP (coefficient of performance). For example a heat pump that has an input of 1000kWh and produces 2,500kWh would have a COP = 2.5.


    You use 6,700kWh and zeupater has assumed your system has a COP of approx 3.0. to give an output 'upwards of 20,000kWh'


    A system COP of 3.0* is excellent and achieved by only a few installations in trials.
  • E.ON Company Representative: Malc
    E.ON Economy 18
    Eon have informed me that the E18 tariff is being withdrawn. This currently enables me to run my ASHP system for 9.04 p per KwH. Does anybody have any advice as to which tariff or supplier to go for? The system runs 24/7 and uses 14000 kWh per annum
    Originally posted by fredwnelson
    Thanks. Not sure where the 20000kwh derives. The house and small development won an award for Green Development of the Year in 2013. Insulation and build of the highest quality levels Energy rating of B (1 point off being A)

    The key issue is the change of tariff by Eon. I need to find out from them how to get the meter changed from E18 and what tariff will work best for me (probably not E7 or E10 methinks)
    Originally posted by fredwnelson

    Hello fredwnelson and about the Economy 18 tariff, I've replied to your other post on a separate thread at the following link.

    https://forums.moneysavingexpert.com/showthread.php?p=76071579&highlight=eon#post760715 79

    Thanks fredwnelson.

    Malc
    Official Company Representative
    I am an official company representative of E.ON. MSE has given permission for me to post in response to queries about the company, so that I can help solve issues. You can see my name on the companies with permission to post list. I am not allowed to tout for business at all. If you believe I am please report it to forumteam@moneysavingexpert.com This does NOT imply any form of approval of my company or its products by MSE"
    • jcontest
    • By jcontest 7th Nov 19, 2:28 AM
    • 145 Posts
    • 570 Thanks
    jcontest
    General Question
    Our old boiler took out a few months ago.
    It was only for Hot Water, so I thought I would take the plunge and go for a GS or AS Heat Pump. I knew that it would be expensive, messy, and time consuming. Off I go to the MCS website to search for a installer. So I get this list, and contacted somewhere between 15 and 20 installers (stopped around 22 miles distance) and only two of those are willing to even entertain giving me a quote. After a week or so of waiting, neither company is willing to talk to me as it's only one person who does quotes and neither company is sure why said person is not contacting me.


    I mean, when I say on the phone that I know GSHP could cost £15-20k, and that underfloor heating is expensive but I still want it. That should be good enough.


    So I just gave up and got regular radiators with a basic Baxi (tho, I regret the controller as it's only On/Off, and not variable heat).


    The cost/benefit for me was not going to be large, if any at all. We have solar PV panels and as such that would bring the energy cost down to a little of nothing during the summer, but having natural gas means we would, likely, be cheaper in the winter with a combi.


    So, the "general" question(s) I have is this.
    Should it be a pain to find a installer? Should I have just searched farther and farther out? (Most who didn't want to talk to me want only Council or Housing Association jobs). The "gas" installers I spoke to had no positive knowledge of heat pumps at all, and none really cared about such tech. My previous car (Leaf Tekna), and current clothes dryer (LG Heat pump, crappy design) have HP tech and I find the negativity of the tech really odd. I am in the North West between Liverpool and Manchester, so it's not a remote part of the UK. Amazing how many installers on the MCS list don't exist. That was another fear. If you cant find a installer, then finding a repair tech could be just as bad if not worse.
    • Jeanners49
    • By Jeanners49 3rd Dec 19, 12:59 PM
    • 15 Posts
    • 1 Thanks
    Jeanners49
    ASHP - not doing what it says on the tin
    Hello,


    My husband was persuaded into buying/having installed an air source heat pump in July this year. The salesman/director who came round to the house (at my husband's invitation) assured us it was the best thing since the proverbial, would drastically reduce our energy bills and we would hardly notice the noise from it. In fact our electricity bills have doubled since the blasted thing was installed (and the bungalow is barely warm) and the noise is unbearable. There's a leak somewhere and the pressure has been consistently unreliable. Although the company have someone on the switchboard, telephone calls/messages appear not to be passed on and my email to the director/salesman on 9 November remains unanswered. We're still waiting for an engineer to come and find the leak/sort the pressure out.

    Additionally, the gas boiler we had before the ASHP was barely two years old and was an A+ efficiency rated Worcester Bosch. If the director/salesman had any sort of conscience he would have told us we would not benefit from having the ASHP installed, but clearly he wanted to make a sale. So now we've paid out £10,850 for a uselss bit of tech and have lost the price of the gas boiler along with the installation costs (another £4,000). I've tried to use Resolver for a complaint but they aren't adding new companies at the moment. I've contacted Citizens Advice but have as yet had no response. I'm at my wits end; we're not wealthy people, my husband is elderly and disabled and the whole business is keeping me awake at night. I'm aware that he should have read up more on the pros and cons but I still feel we've been ripped off and mis-sold a uselss piece of junk.
    Where to go from here?
    • pd001
    • By pd001 3rd Dec 19, 1:45 PM
    • 868 Posts
    • 239 Thanks
    pd001
    Hello,


    My husband was persuaded into buying/having installed an air source heat pump in July this year. The salesman/director who came round to the house (at my husband's invitation) assured us it was the best thing since the proverbial, would drastically reduce our energy bills and we would hardly notice the noise from it. In fact our electricity bills have doubled since the blasted thing was installed (and the bungalow is barely warm) and the noise is unbearable. There's a leak somewhere and the pressure has been consistently unreliable. Although the company have someone on the switchboard, telephone calls/messages appear not to be passed on and my email to the director/salesman on 9 November remains unanswered. We're still waiting for an engineer to come and find the leak/sort the pressure out.

    Additionally, the gas boiler we had before the ASHP was barely two years old and was an A+ efficiency rated Worcester Bosch. If the director/salesman had any sort of conscience he would have told us we would not benefit from having the ASHP installed, but clearly he wanted to make a sale. So now we've paid out £10,850 for a uselss bit of tech and have lost the price of the gas boiler along with the installation costs (another £4,000). I've tried to use Resolver for a complaint but they aren't adding new companies at the moment. I've contacted Citizens Advice but have as yet had no response. I'm at my wits end; we're not wealthy people, my husband is elderly and disabled and the whole business is keeping me awake at night. I'm aware that he should have read up more on the pros and cons but I still feel we've been ripped off and mis-sold a uselss piece of junk.
    Where to go from here?
    Originally posted by Jeanners49
    Did you pay for any of the work using a credit card?
    • matelodave
    • By matelodave 3rd Dec 19, 1:59 PM
    • 4,812 Posts
    • 3,114 Thanks
    matelodave
    You could try the CAB or Trading Standards dept of your local council however unless you've got all the paper work to substantiate the claim that the unit would work out cheaper to run than the boiler it will be difficult to prove miss-selling.

    TBH its never a good idea to just replace a boiler with a heatpump unless the rest of the system is upgraded at the same time. Have you got all the design specifications for the system, the MCS certificate and most important has the system been registered for Renewable Heat Incentive Payments, which should hep you recover some of the cost over seven years
    Never under estimate the power of stupid people in large numbers
    • richardc1983
    • By richardc1983 3rd Dec 19, 2:23 PM
    • 1,999 Posts
    • 1,038 Thanks
    richardc1983
    Hello,


    My husband was persuaded into buying/having installed an air source heat pump in July this year. The salesman/director who came round to the house (at my husband's invitation) assured us it was the best thing since the proverbial, would drastically reduce our energy bills and we would hardly notice the noise from it. In fact our electricity bills have doubled since the blasted thing was installed (and the bungalow is barely warm) and the noise is unbearable. There's a leak somewhere and the pressure has been consistently unreliable. Although the company have someone on the switchboard, telephone calls/messages appear not to be passed on and my email to the director/salesman on 9 November remains unanswered. We're still waiting for an engineer to come and find the leak/sort the pressure out.

    Additionally, the gas boiler we had before the ASHP was barely two years old and was an A+ efficiency rated Worcester Bosch. If the director/salesman had any sort of conscience he would have told us we would not benefit from having the ASHP installed, but clearly he wanted to make a sale. So now we've paid out £10,850 for a uselss bit of tech and have lost the price of the gas boiler along with the installation costs (another £4,000). I've tried to use Resolver for a complaint but they aren't adding new companies at the moment. I've contacted Citizens Advice but have as yet had no response. I'm at my wits end; we're not wealthy people, my husband is elderly and disabled and the whole business is keeping me awake at night. I'm aware that he should have read up more on the pros and cons but I still feel we've been ripped off and mis-sold a uselss piece of junk.
    Where to go from here?
    Originally posted by Jeanners49
    This has happened to so many people who had mains gas. Mains gas (whilst the ASHP will be more efficient) is still cheaper per unit than electricity is so this makes mains gas the cheaper form of heating. So if you have anything other than mains gas as your heating system e.g oil or electric element heaters then ASHP is your best and cheapest option.

    Not sure where you are located but it might be worth giving a proper company a call who maintain and service these units and check that the system is set up the best it can be... also to check that radiators have been oversized as a 4kw radiator designed to run at 80c flow temp will be outputting approx 800w at 35c flow temp of a heat pump etc. If radiators have not been changed to larger radiators to account for the lower flow temps of a heat pump then you might as well keep the system off as it will never heat your home effectively and you will waste so much energy doing so.

    I can recommend https://www.freedomhp.co.uk/ ask for Graham Hendra, they put right what a lot of others have not put right.

    From giving advice to others who had the same exact issues it's sometimes better to cut your losses and put a gas boiler back in and try to sell the heat pump and recoup some of your money back.
    If you found my post helpful, please remember to press the THANKS button! --->
    • Jeanners49
    • By Jeanners49 3rd Dec 19, 2:45 PM
    • 15 Posts
    • 1 Thanks
    Jeanners49
    MateloDave, we had the whole works; new double radiators etc and have the required certificates. Am trying to apply for domestic RHI but the recent EPC (which was done for the installation) says that we don't have enough roof insulation (an average thickness was taken) and because the only bit with no insulation is a small piece of boarding less than 1 square metre, no company wants to do it unless we pay a small fortune.
    • Jeanners49
    • By Jeanners49 3rd Dec 19, 2:50 PM
    • 15 Posts
    • 1 Thanks
    Jeanners49
    Thanks for this - I think my husband is reluctant to throw any more money at the heating by consulting another company. We're based near Ringwood and he chose a local installer because he thought they would be reputable. Fat chance..

    Radiators were all replaced and the ASHP is an LG, so is a good one.

    Cutting our losses is a hard one to swallow, but unless we take the guy to court, I think it's our only option.



    This has happened to so many people who had mains gas. Mains gas (whilst the ASHP will be more efficient) is still cheaper per unit than electricity is so this makes mains gas the cheaper form of heating. So if you have anything other than mains gas as your heating system e.g oil or electric element heaters then ASHP is your best and cheapest option.

    Not sure where you are located but it might be worth giving a proper company a call who maintain and service these units and check that the system is set up the best it can be... also to check that radiators have been oversized as a 4kw radiator designed to run at 80c flow temp will be outputting approx 800w at 35c flow temp of a heat pump etc. If radiators have not been changed to larger radiators to account for the lower flow temps of a heat pump then you might as well keep the system off as it will never heat your home effectively and you will waste so much energy doing so.

    I can recommend https://www.freedomhp.co.uk/ ask for Graham Hendra, they put right what a lot of others have not put right.

    From giving advice to others who had the same exact issues it's sometimes better to cut your losses and put a gas boiler back in and try to sell the heat pump and recoup some of your money back.
    Originally posted by richardc1983
    • Jeanners49
    • By Jeanners49 3rd Dec 19, 2:51 PM
    • 15 Posts
    • 1 Thanks
    Jeanners49
    Debit card...


    Did you pay for any of the work using a credit card?
    Originally posted by pd001
    • richardc1983
    • By richardc1983 3rd Dec 19, 2:52 PM
    • 1,999 Posts
    • 1,038 Thanks
    richardc1983
    because the only bit with no insulation is a small piece of boarding less than 1 square metre, no company wants to do it unless we pay a small fortune.
    Originally posted by Jeanners49
    Could a handyman do the remaining insulation for you given that it is such a small area?
    If you found my post helpful, please remember to press the THANKS button! --->
    • richardc1983
    • By richardc1983 3rd Dec 19, 2:54 PM
    • 1,999 Posts
    • 1,038 Thanks
    richardc1983
    Thanks for this - I think my husband is reluctant to throw any more money at the heating by consulting another company. We're based near Ringwood and he chose a local installer because he thought they would be reputable. Fat chance..

    Radiators were all replaced and the ASHP is an LG, so is a good one.

    Cutting our losses is a hard one to swallow, but unless we take the guy to court, I think it's our only option.
    Originally posted by Jeanners49
    If the system is an LG then it might be worth contacting LG technical who are in the UK and are very good.

    I will drop you a PM with info. Graham Hendra at freedom HP I gave earlier used to be the head technical guy at LG technical hence why I recommended them.

    I think you are going to have to have someone in to check the system is set up correctly as many issues with these systems are commissioning issues, however, this system even when setup at it's most efficient will cost more to run than a gas boiler would at 6p per unit of gas vs 13p of electric!

    So I wouldn't give up just yet but even after others have tried and had the system setup at it's optimum they ended up putting a gas boiler back in, however you will take a long time to recoup that cost so it may be worth trying to get the ASHP setup properly.
    Last edited by richardc1983; 03-12-2019 at 3:19 PM.
    If you found my post helpful, please remember to press the THANKS button! --->
    • pd001
    • By pd001 3rd Dec 19, 3:25 PM
    • 868 Posts
    • 239 Thanks
    pd001
    Debit card...
    Originally posted by Jeanners49
    If you had paid by credit card you may have been able to hold them responsible if the system hasn't been set up, or finished off correctly.
    I am not sure if payment by debit card gives you the above extra protection
    • zeupater
    • By zeupater 3rd Dec 19, 4:28 PM
    • 4,975 Posts
    • 6,733 Thanks
    zeupater
    Could a handyman do the remaining insulation for you given that it is such a small area?
    Originally posted by richardc1983
    Agree .... Needed to go to one of the Destroy-It-Yourself sheds at the weekend & noticed that the whole self serve checkout area was full of rolls of loft insulation so if it's a small area it should be pretty quick and easy!!

    HTH
    Z
    "We are what we repeatedly do, excellence then is not an act, but a habit. " ...... Aristotle
    • matelodave
    • By matelodave 3rd Dec 19, 4:47 PM
    • 4,812 Posts
    • 3,114 Thanks
    matelodave
    MateloDave, we had the whole works; new double radiators etc and have the required certificates. Am trying to apply for domestic RHI but the recent EPC (which was done for the installation) says that we don't have enough roof insulation (an average thickness was taken) and because the only bit with no insulation is a small piece of boarding less than 1 square metre, no company wants to do it unless we pay a small fortune.
    Originally posted by Jeanners49
    It's not expensive to get a roll or two and put it up there yourself or get someone to help you. Getting the RHI could net you several thousand pounds (I;ll get over £5k) so dont forfeit it for something trivial. Improving your insulation will also make your heating more effective.

    If he system was properly designed are you using it properly? T

    Trying to run it in an on/off manner like a gas boiler is likely to cost you a lot more than having it idling away for a lot longer. Because it should be running at a lower temperature (usually around 35-40 degrees, rather than 70 or so with a gas boiler).

    It will take a lot longer to reheat the place. We don't turn ours off over night, just down a couple of degrees and back up in the morning before we get up. Likewise we dont have our hot water everso hot.

    Running an ASHP at higher temperatures and calling for very hot water has the undesired effect of increasing the running costs and in many cases using the back-up heater which really ramps up the bills.
    Never under estimate the power of stupid people in large numbers
    • DD137
    • By DD137 3rd Dec 19, 7:51 PM
    • 10 Posts
    • 3 Thanks
    DD137
    Evening All,


    We've recently moved into a house with one of these systems installed and are finding it to be quite frustrating. Are they meant to omit a humming noise? When the heating is on the pump is always gurgling away with a low hum which occasionally gets louder before subsiding again.



    The previous owners installed it in a bedroom cupboard which has basically rendered the room unusable, why they didn't just get a combi boiler I don't know. Its like the engine room of the Starship Enterprise in there with all the equipment humming away.
    • matelodave
    • By matelodave 3rd Dec 19, 8:05 PM
    • 4,812 Posts
    • 3,114 Thanks
    matelodave
    Have you heard how much noise a combi boiler makes?

    The noise you can hear is the circulating pump which is similar to the one in a combi, on top of that the combi has a gas burner and a combustion fan which kick in and out as the boiler fires up
    Last edited by matelodave; 03-12-2019 at 8:09 PM.
    Never under estimate the power of stupid people in large numbers
    • DD137
    • By DD137 3rd Dec 19, 8:14 PM
    • 10 Posts
    • 3 Thanks
    DD137
    The modern combi boiler in my previous house was a lot quieter when running, you'd have to be stood next to it to notice it was on.



    I was hoping there a solution other than ripping the thing out as it seems quite a waste considering it was only installed this year and how expensive they are
    • richardc1983
    • By richardc1983 4th Dec 19, 9:13 AM
    • 1,999 Posts
    • 1,038 Thanks
    richardc1983
    The modern combi boiler in my previous house was a lot quieter when running, you'd have to be stood next to it to notice it was on.



    I was hoping there a solution other than ripping the thing out as it seems quite a waste considering it was only installed this year and how expensive they are
    Originally posted by DD137
    I have a modern top of the range condensing boiler approx 2 years old, it is quiet but not silent. The fan, combustion gas burner & pump can all be heard in the cupboard that it is installed in. Once the door is closed there is a slight hum can he heard on the outside.

    What model do you have, it may be that you can turn the fan speed down? However, if you are considering ripping it out due to the noise you would be better off building a cupboard round it or insulating the existing one for noise.
    If you found my post helpful, please remember to press the THANKS button! --->
Welcome to our new Forum!

Our aim is to save you money quickly and easily. We hope you like it!

Forum Team Contact us

Live Stats

3,711Posts Today

7,047Users online

Martin's Twitter