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bazhef
27-05-2014, 01:53 PM
Hello,

I am in the process of building a house, in Northern Ireland, and I am installing a geothermal heat pump along with underfloor heating.
My supplier had been recommending a Danfoss Opti Pro DHP-L 12kW pump.
However, he has recently became an agent for EcoForest and is now recommending one of their pumps to me, a 3-12kW pump.
As a novice, i am not sure whether to make the switch or not so hopefully someone here has experience of both and can advise.
The proposed difference in cost in negligible so it basically comes down to which is the best unit.

The information he has priovided me with to make the switch is as follows:
1. COP of 4.6 according to EN 14511 S0⁰C/W35⁰C, including circulation pumps and the inverter.
2. They are the only heat pump manufacturer currently using a Copeland Inverter Type compressor in their heat pumps other manufacturers are only testing this now and are starting to catch up.
3. The new Alfa Laval heat exchangers in the Heat Pump helping them achieve this COP.
4. The high level of competency of their Engineers and their eagerness to have the market leading ground and air source heat pump technology.
5. Additional Control features and willingness to adapt their software to suit the particular requirements of our market.
6. The compressor ranges from 3-12kw and will learn the heat loss requirements of the house. Once it does this, it will only run at whatever speed it needs to maintain the house at a constant temperature. As a designer and installer of heat pump technologies this is a perfect solution for us as we were always relying on the insulation being installed in a property matching the U-value and air tightness target figure given to us on paper, which does not always happen. Having the scope to vary the heat output eliminates any possible under sizing or over sizing issues. Not that this happens much but you never know what way a builder may cut corners with insulation, which we would never see!

So if there is anyone who can help me it would be much appreciated as it is a big decision.
I understand that the end decision is mine but any personal opinions would help make that decision although i won't hold you to it!
If you need any further information, let me know and i'll do my best to find it our for you.

jdunc2301
27-05-2014, 07:17 PM
I work for a leading heat pump manufacturer, if you want me to run through some things pm me and I can give you a call.

I'm not a sales chap, engineer

install monkey
27-05-2014, 08:15 PM
jdunc he didnt say he had money to burn!:rolleyes:haha


I work for a leading heat pump manufacturer, if you want me to run through some things pm me and I can give you a call.

I'm not a sales chap, engineer

frank
27-05-2014, 08:28 PM
The only advice I can give really, is the same as with all sales pitches, ...ask to speak to some of their previous customers and see what they say, see some of their previous installations, then make up your mind.

If you need help with technical comparisons, we can help with that.

jdunc2301
27-05-2014, 08:34 PM
jdunc he didnt say he had money to burn!:rolleyes:haha

Pointless post mate...

jdunc2301
27-05-2014, 10:56 PM
Hello,

I am in the process of building a house, in Northern Ireland, and I am installing a geothermal heat pump along with underfloor heating.
My supplier had been recommending a Danfoss Opti Pro DHP-L 12kW pump.
However, he has recently became an agent for EcoForest and is now recommending one of their pumps to me, a 3-12kW pump.
As a novice, i am not sure whether to make the switch or not so hopefully someone here has experience of both and can advise.
The proposed difference in cost in negligible so it basically comes down to which is the best unit.

The information he has priovided me with to make the switch is as follows:
1. COP of 4.6 according to EN 14511 S0⁰C/W35⁰C, including circulation pumps and the inverter.
2. They are the only heat pump manufacturer currently using a Copeland Inverter Type compressor in their heat pumps other manufacturers are only testing this now and are starting to catch up.
3. The new Alfa Laval heat exchangers in the Heat Pump helping them achieve this COP.
4. The high level of competency of their Engineers and their eagerness to have the market leading ground and air source heat pump technology.
5. Additional Control features and willingness to adapt their software to suit the particular requirements of our market.
6. The compressor ranges from 3-12kw and will learn the heat loss requirements of the house. Once it does this, it will only run at whatever speed it needs to maintain the house at a constant temperature. As a designer and installer of heat pump technologies this is a perfect solution for us as we were always relying on the insulation being installed in a property matching the U-value and air tightness target figure given to us on paper, which does not always happen. Having the scope to vary the heat output eliminates any possible under sizing or over sizing issues. Not that this happens much but you never know what way a builder may cut corners with insulation, which we would never see!


1. The COP your specifying is realistic, our equivalent 12kw is showing a 4.30 according to EN....
2. The brand of the compressor is neither here nor there as far as end user goes, yes there aren't many inverter ground source on the market, I believe ours is due for release in a few months, but with fairly steady temperatures the uptake has been slow
3. I think the selling point of the heat exchanger can be ignored, the COP's are comparable so not really a point to think about, unless that HX is giving the extra .30 ;)
4. Everybody wants to be a market leader, all you want is a product with a decent warranty that will last I wouldn't take this into account
5. Premium ground source units will have control functions built in that can accommodate different climates and set-points, our units do this they are adaptable from Swedish climate to Spanish climate, I think it should be standard with a premium product not a selling point really
6. The U value of the house should be calculated to give your design indoor temperature based on the design outdoor...so 21'c indoor @ -3'c outdoor, the HP should be sized to this so it can achieve the design temps. Yes when it is above these temps the performance increases and the compressor will back off to give say 5kw. However that's only in heating, normally on fixed speed there will be a buffer tank between heat pump and heating system, so if there is a demand the unit can dump excess heat to buffer tank before cycling off. The inverter will merely look at the desired flow temp and lower the compressor speed to suit and match within 5k (example) so potentially removing the need for a buffer.
In my experience In domestic hot water mode the unit will have a high effect and low effect fixed compressor speed based on difference between actual and setpoint so lets say 10kw and 7kw...
Make sure the HP is sized correctly.

I would look for;
1. Warranty period, some manufacturers are offering 7 year warranties now in-line with the RHI and some only 3 years
2.Customer reviews, go and have a look at one of the previous jobs
3. Functionality, can the unit be remotely controlled if on holiday etc
4. Spares back-up
5.Long term servicing costs

Feel free to PM

bazhef
28-05-2014, 04:01 PM
Thanks guys.
I had sent an email back to My supplier/installer yesterday and had covered some of those points.
The issue with getting customer reviews is that the manufacturer is only breaking into the NI market and my installer has only supplied 2 of their pumps and to be honest they wouldn't be running long enough for a decent review.
I'll contact him again for some technical data so maybe you guys can assess the two pumps in question.

jdunc,
what do you mean by "fairly steady temperatures" making the uptake slow?
I thought that would be a plus point??

My installer has carried out calculations of the u values air tightness etc so i am confident enough that the pump is is adequate.
Others i had got to price also came in around the same size of a pump for the majority of the quotes.
I'm just not sure about the variable output i.e. 3-12kW when the Danfoss i had previously been quoted for was a fixed 12kW.

jdunc2301
28-05-2014, 06:22 PM
What are you not sure about with the 3-12kw?

When the unit needs to provide 12kw to meet your heatload on the property it will At design outdoor, And any Lower output required it can match the kW requirement.

Ground temps are fairly stable, say a 6-10k fluctuation whereas air temperatures can fluctuate by 40k.

Fixed speed compressor = fixed speed pumps on heating side and ground collector side

Variable speed = modulating pumps with requirement

bazhef
30-05-2014, 12:21 PM
What are you not sure about with the 3-12kw?

When the unit needs to provide 12kw to meet your heatload on the property it will At design outdoor, And any Lower output required it can match the kW requirement.

Ground temps are fairly stable, say a 6-10k fluctuation whereas air temperatures can fluctuate by 40k.

Fixed speed compressor = fixed speed pumps on heating side and ground collector side

Variable speed = modulating pumps with requirement

Ah right, when you said fairly stable temps i thought you meant output temps DOH!