Air Source Heat Pumps

[mark6266]

Hi chaps and chapess's
Has anyone had any experience in thease fellas ?? (new fangled thingy)
Manufactures claim for every 1kw of electrical energy the pump uses it produces 3 kw of heat energy , flow temp goes to a max of 50 deg c, and rads there for have to be oversized ect .
welcome all feed back
kind regards mark.
oh who am I ?
My name is mark and I am a time served ex gas now oil heating engineer / plumber .
Very busy at the moment (opening a shop ect) so very little time to offer advice , thinking about geting the air source heat pump to heat the shop .

 

[mark6266]

Well thats me converted . We have just finnished the garage conversion c/w ashp , what a great piece of kit . I can now go into a customers house and with my hand on my heart I can honestly say I want one in my own home to heat my hot water / central heating ..
thanks guys

all the best mark

 

[Raymundi]

Hi Mark, i have just had an air flow heat pump fitted, its 11kw output and heats underfloor heating downstairs and 5 radiators upstairs. The heating out put is very good and hot water easily achieves the 45 degrees ive set it for. Overall im very happy plus the Gov is offering a 30 percent grant. Only prob ive had is the digital thermostats ive had installed to cover two downstairs zones, they dont seem to work properly and constantly click, Polypipe PB PZP.

 

[borderfox]

[FONT=&quot]I have been reading this thread with interest and have some questions that I hope some of you can help with.[/FONT]

[FONT=&quot]I currently have a 4bed semi with oil boiler and rads. I want to install an Air-water heat pump - and have it set to kick in only when it is economical to use, with the oil boiler kicking in otherwise.[/FONT]

[FONT=&quot]What issues arise when adding a system to an existing oil boiler/rads setup?

I have heard the difference with using them in this part of the world in comparison with Scandanavia is that there is an issue with them icing up due to the humidity in our climate. Whilst they are equipped with the ability to deice - this costs a fortune in lecky. I have read about people who have put built their own diy housing around the unit to help overcome this problem. Has anyone any thoughts on this particular issue?
[/FONT]
[FONT=&quot]I have a list of systems - and before I even start looking at the specs, what exactly is important?[/FONT]

[FONT=&quot]Are there any systems folks here would recommend (and if so for what reason)? By the same token, are there systems you would suggest not to touch with a barge pole?[/FONT]

 

[BLOD]

Hi,
Interesting topic, I haven't fitted one of these (yet), How noisy are they ? Has anyone who's fitted one had any complaints about the noise ?

Delonghi do one with an advertised heat output of 65 degrees !


Thanks
blod

 

[Raymundi]

Hi,
Interesting topic, I haven't fitted one of these (yet), How noisy are they ? Has anyone who's fitted one had any complaints about the noise ?

Delonghi do one with an advertised heat output of 65 degrees !


Thanks
blod

I have fitted an NIBE VVM300 and i was worried about the noise level too but the noise level has turned out to be minimum. Our unit is right outside our bedroom window and doesnt disturb us.

 

[BLOD]

Hi Raymundi, thanks for the reply.
Are you pleased with its heat output during the recent cold weather ?

regards
blod

 

[borderfox]

I have fitted an NIBE VVM300 and i was worried about the noise level too but the noise level has turned out to be minimum. Our unit is right outside our bedroom window and doesnt disturb us.

Are you using just this unit - or is this a primary/secondary heating source?
Output to rads or underfloor?
What are your lecky bills looking like?

 

[Raymundi]

Hi Raymundi, thanks for the reply.
Are you pleased with its heat output during the recent cold weather ?

regards
blod

Yeah the output is very good, in fact to good sometimes as the system can be hard to regulate like a normal gas or electric heating system. We have had temp here this last few weeks of between minus 1 and minus 10 and our house has remained roasting.

We have underfloor heating downstairs (which prob doesnt help with the regulating) and rads upstairs (when using rads you need to use high output rads)

Hi the lecky bills are about £60 per month but that includes lighting etc. We will prob turn the system on to hot water supply only in May through till about Oct which will bring the bills down further. We have rads upstairs and underfloor downstairs.

 

[Jimbob]

Yeah the output is very good, in fact to good sometimes as the system can be hard to regulate like a normal gas or electric heating system. We have had temp here this last few weeks of between minus 1 and minus 10 and our house has remained roasting.

We have underfloor heating downstairs (which prob doesnt help with the regulating) and rads upstairs (when using rads you need to use high output rads)

Hi the lecky bills are about £60 per month but that includes lighting etc. We will prob turn the system on to hot water supply only in May through till about Oct which will bring the bills down further. We have rads upstairs and underfloor downstairs.

This can be solved with the installation of a buffer tank. Basically a tank which creates a second circuit, so a primary circuit from the heat pump to a tank, directly flowing round heating the tank, this could also be linked in with a towell rad if you fancy. Then a second circuit with another pump going from the buffer to the heating system. not 100% sure how it would be piped with regards to a DHWC though, would probably also come off the second circuit.

Down side to buffer tanks is that they need to be quite large to be effective

 

[Renewable M]

Hi guys.

I spend all day every day dealing with ASHP's in one capacity or another. (well I would do, wouldnt I..)

Here are some tidy points.

Beware the heat pumps which are a converted chinese water heater like the trianco and many others. They have no way of talking to the heating and hot water controls so you're up the creek for controlling the things. What good is a time controller that has no relationship with your heating y or s plan?????

Heat pumps (many) will achieve 65 degrees no problem.

Heat pumps are less efficient at lower temperatures. Usually these are the R417A units. These are just old R22 technology and will become a thing of the past. R410A is good.

The regulations for buffer vessel sizing : No less than 12litres per kw of output.

Heat pumps are more efficient when the load on them is not so high. They will return greater efficiency and fuel savings if your heating only needs a 45 degree flow than a 60 degree flow.

Good air source units will allow 2 set temperatures- one for heating and a higher temp for hot water.

Good air source heat pumps will have switched live for the backup boiler and IMPORTANTLY you should be able to set the outside temp at which the boiler kicks in. These units which have a fixed temperature are next to pointless. One temperature does not suit every home. (The Bivalent point)

There are considerable savings to be made against oil, but less against a well designed (not many of them) gas condensing system (not a combi).... the unit cost of gas is lower.

You will not get legionella from a heat pump.

Choose a scroll compressor over a rotary. If you can get one with vapour injection, you're laughing.

Have i got one....YES!
Have my parents got one.....YES!

Problems with noise? No.
Were we cold over the last few weeks? No.

If anyone wants to come and see one running, on a real house with old radiators and not great thermal efficiency, then let me know. You are more than welcome. Bring your own biscuits, I'll put the kettle on.

this is who I work for, and the all singing and dancing units start at £1950. Compare that to a trianco which is useless at low temps and has no heating controls and theres no contest.

 

[rob75]

I've just come across this thread which is very informative and exciting, I got to the last post on page 4 disappointed that I had reached the end of the thread.

I'm in the middle of an installation of an 8kw Ecodan. I'm waiting for my system to be commissioned and now that my old Gas boiler has been ripped out and I have no heating I feel vulnerable and although I am excited to get my system online I'm now starting to panic a little.

With regards to 'good' ASHP units, is the Ecodan one of the better ones. Being a Mitsubishi I am hoping so! I knew NOTHING about any type of heating systems (traditional or new 'greener' technologies) so please bear with me.

My slight concern is the immersion heater on the water cylinder having been told that traditional IH are expensive to run. Although I think I read above that this can be set to boost water temperature once a week to kill Legionella?

I was the system's biggest advocate whilst waiting for delivery, now I am in limbo land waiting for commissioning I'm searching the web and finally I have come across some positives on this thread.

Any feedback regarding the Ecodan would be appreciated.

Many thanks,

Rob.

 

[quality]

The Ecodan is not a bad piece of kit it depends mainly on the designer of the system as to weather it performs as its supposed to and weather its got the required capacity that needed not just whats calculated

 

[kellogs71]

For me the price of Air Source hat pumps is unrealistic. Yes, of course you can buy them for less than 2k but are they UKAS and MCS registered? I doubt it. they are not registered for a reason. They are sh*t! MCS is a body that will only accredit thos heat pumps that will work in the UK.

The other problem is that those that are UKAS and MCS accredited are very expensive. So you have to judge between the two UKAS and MCS or not? My take is dont buy thos that are not accredited as you will be cold and have big bills. The only answer is to find those accredited and well priced. Heres one Ive found huskyheatpumps.co.uk

 

[ecowarm]

MCS accredited Ashp £2000ish speak to unguided1 one he's installed loads

 

[kellogs71]

Do they include a free buffer and hot water tank? Sounds Ok at that price. Mike

 

[rob75]

I'm not sure why you say the price is "unrealistic".

How much is a decent boiler at present (fitted) - around £2000? The Ecodan ASHP and the water cyclinder is around £6000 but with the grant and/or renewable heating inititative the who system will pay for itself within a couple of years. Sure there is some initial investment involved but long-term it will pay.

Like anything you get what you pay for with regards to the pump.

Rob.

 

[ecowarm]

Do they include a free buffer and hot water tank? Sounds Ok at that price. Mike

Have a look here Air Source Heat Pumps, Solar, Renewable Energy, UK, Southern Ireland, Scotland, Wales - Earth Save Products Ltd I'm going to see them next week.

 

[MrC]

As an installer of heat pumps for over 15 years its interesting to see some some interesting comments.
They are more efficient than any other heating system, even nat gas down to just below 0C, they are less efficient at higher output temps and to get 65C in the cylinder for legionella protection we fit a time clock to switch on for 1 hour per week to increase the temp. If using electric showers this option isn't really required as its the fine mist possible in a shower that may transfer the virus. Think I read somewhere you are more likely to be stuck by lightening twice beforehand!!
Heatpumps work well with double convectors or indeed fan coil units, cheaper units are better just for underfloor heating or just for DHW
Mike
ps, am a refrigeration engineer too so know all about the working of these things.