Nibe Fighter 360p ashp costing me loads to run

John_Pierpoint

I think we are getting as bit off topic here; so I will resist the urge to comment.

jasonoldy69

this looks interesting - nibefighter360p.somee.com

John_Pierpoint

http://nibefighter360p.somee.com/

"From April 2008, all social housing must achieve a minimum of code level 3 of the Code for Sustainable Homes. This will mean developers will find it hard to just install traditional systems and will have to look at alternatives, this especially on apartment blocks that have been predominately electrically heated" he suggests.
[PHIL HURLEY, managing director of NIBE UK, ]

"First option could be solar but it will still only be for hot water. You still have to heat the place."

Gas, he adds, is also a nightmare. Often when a building is knocked down to be replaced with apartments, there is one gas main and this would need to be up-rated with costs running into thousands. Then there is the cost (and work involved) of flueing each apartment.

The building is ripe for exhaust air heat pumps. They will fit in the cupboard which was originally for the cylinder and work with radiators or underfloor. Because of the air tightness, the developer would have had to install ventilation in the wet areas anyway. [not to mention the ongoing hassle of all those gas safe certificates each year]

"For the developer, it is a win-win situation. It is easy to install. There is not much to change. It will count towards the code level 3 standard and the 20% carbon reduction target." And developers should not forget that next year Code level 3 will be the norm for all new-build housing.

Fortunately the experiments conducted at the expense of social housing, should result in an assumed CoP of 2.3 and thus rule out heat pumps as an alternative to cheap gas.

http://www.heatingandventilating.net/news/news.asp?id=6378

Also of interest: Dominic Littlewood investigates a block of flats in Southend on Sea where the frames of double glazed windows streamed with condensation.

Two years later the BBC demonstrated that the architect had specified the windows to be sealed to the inner leaf of the well insulated cavity wall and the builder had installed them, open to the the cold outside air, on the outer leaf and wondered why the silicone sealer on the inside was going black with mould.
Do we have a rocket scientist to explain these things to invisible managing directors in the building industry?

C&M

Dom investigates who is responsible for sorting out problems with new build homes.
First broadcast : 20 Apr 2012

londonsouth

Please help

I have been reading this thread for the last few days and I am just starting to understand some complicated terms.

I have recently moved into the the new property. It is a new build. It is a shared ownership property. NIBE 205 F has been installed in it. It is electric underfloor heating. There is no gas supply. The first month I had 180 pounds electricity bill. Since then I have been trying to save some money but being cold I have started using the heating again. I check electricity consumption every day.

The flat is draugty and cold. The freezing cold air was blowing straight into the living room through the holes in the walls that are part of the" heating" design. It felt like sitting in the park on my sofa in the middle of the winter. The outside air is not blown into the property like with 360 model. I have changed the caps on the ventilation holes to the sliding ones in hope that I would be able to control the amount of air that comes into the room but it is still bad. Draughty. I am aware that it is a part of the heating design but it just does not make any sense. I am considering blocking the ventilation holes completely. Surely I would get warm and save some money. Why do I need them? If I need fresh air I will open a window. I would like to hear other people's experiences and views on this one.

The building was completed seven month sago, Can somebody please let me know what you mean by snag the boiler by NHBC? Do you mean they would change the boiler or adjust it?

It is so depressing, my first place . The place is so draughty that you can feel the air blowing around. And I was promised it was the most economical mean of heating the place. I am considering installing electric radiators and use the boiler just for hot water. Again, I just want to get warm and save some money.

Do I stand a chance to do something about it on my own?

Thank you

londonsouth

What a disappointment.

John_Pierpoint

If you watch the programme link in my posting above, it will give you some idea of what you are up against for even the most obvious obvious errors in building to achieve modern standards.

In theory you should be living in a property where the scientists can remove your front door and replace it with a big fan blowing inwards. For the property to achiever compliance with the modern regulations it should be so draught proof that the fan achieves a measurable higher pressure inside, when compared with the air pressure outside.
The reality is that you probably have a property with ideas understood in theory by guys working at the modern equivalent of drawing boards BUT built by labour that hasn't a clue.

lovesfarmbpha

A question was put to housing association BPHA about if the NIBE 360 system has a boiler interlock this is the answer that was given(yeah but no but yeah but!)
"We have done our best to get to the bottom of this. What we are being told is that the NIBE unit does not have an interlock as such but has mechanisms within it that perform the same function, which accounts for seemingly contradictory information. The difficulty we have in providing explanations is that we are trying to comment on technical aspects of someone else's product. We believe that the product complies with relevant legislation but for a more detailed explanation of the product's workings, this will need to come from NIBE direct."

That's probably the best non answer that has ever been given.:rotfl:

albyota

lovesfarmbpha wrote: »

A question was put to housing association BPHA about if the NIBE 360 system has a boiler interlock this is the answer that was given(yeah but no but yeah but!)
"We have done our best to get to the bottom of this. What we are being told is that the NIBE unit does not have an interlock as such but has mechanisms within it that perform the same function, which accounts for seemingly contradictory information. The difficulty we have in providing explanations is that we are trying to comment on technical aspects of someone else's product. We believe that the product complies with relevant legislation but for a more detailed explanation of the product's workings, this will need to come from NIBE direct."

That's probably the best non answer that has ever been given.:rotfl:

Hi, I think you will find that the 'Boiler Interlock' referred to by MCS 3005 v3, is where a Bivalent system exists, i.e a Heat pump that provides the heating and hot water requirements for the dwelling most of the year.... and down to say minus 5 degrees, then a backup Gas / Oil / LPG boiler takes over at lower temps, the 'interlock' being the controls 'Frost stat / Relay, which automatically switch off the heat pump and fire up the boiler, so that they cannot be run together.

your Nibe exhaust air heat pump is the only source, therefore, no requirement for an interlock.

AL

John_Pierpoint

I still cannot understand how this Nibe exhaust air heat pump can ever work on a typical cold winter's day.
Let us pretend that the outside temperature is zero centigrade and the internal temperature is being held at at acceptable 21 degrees. Let us also assume that the pump is capable of producing three units of heat from one unit of electricity, thus giving it a chance to compete with a condensing gas boiler, whose power supply is perhaps one third the cost of electricity. Let us also assume that the home has perfect insulation (Aerogel or better) and no air leaks (draughts) other than the incoming air that is being preheated by the output of the heat pump.
So the incoming air is being heated by 21 degrees and only one third of that heat is electricity ! This means that 7 degrees of the preheated air is from the electricity and 14 degrees of the preheated air comes must come from the outside air, as in reality there is virtually no heat stored inside the building.

So somewhere along the line volume for volume the outside air must be being cooled to minus 14 degrees to make up for heat being lost from the building. As the output air fins from an air source heat pump at minus 14 degrees would be a solid block of ice - that is obviously not what is happening.

I just cannot see how this heat pump is ever going to be something that can add more than a small percentage of extra heat to a building otherwise heated by a cheap form of heat - be that "cheap" gas or a ground source heat pump.
The tenants might as well be on night storage heaters and a whole lot less air changes per day.
The only purpose of the exhaust air heat pump is to allow the "ventilate right" bit of the "build tight & ventilate right" mantra to work, for its mould reduction and health benefits of the tenants.

grahamc2003

John_Pierpoint wrote: »

So the incoming air is being heated by 21 degrees and only one third of that heat is electricity ! This means that 7 degrees of the preheated air is from the electricity and 14 degrees of the preheated air comes must come from the outside air, as in reality there is virtually no heat stored inside the building.

So somewhere along the line volume for volume the outside air must be being cooled to minus 14 degrees to make up for heat being lost from the building. As the output air fins from an air source heat pump at minus 14 degrees would be a solid block of ice - that is obviously not what is happening.

I.

I think there's a couple of misconceptions in these two paragraphs. (I went through a similar exercisea few months agfo, I think on this thread, and convinced myself that the theory it works under is sound - afterall, these things work in other countries).

Yes - as a first cut approximation, 7 degrees of the heating comes from (most of) the electricity consumed (by the compression of the working fluid), but no, that doesn't mean the other 14 degrees comes 'from the outside air'. The other 14 degrees comes from the exhaust air, which is at 21C in your example. So in theory, all the heat pump has to do is lower the exhaust air from 21C to 7C - and that's very easy to do, considering Ecodans cool the outside air from -5C to probably -40C (imo) in order to extract the 8kW they supply. In fact, you've stumbled across the great advantage of exhaust air heatpumps (in theory!) - that is the avoidance under normal circumstances of icing, which is the real pain in the neck for non-exhaust type air pump.

Another way of looking at the theory of these exhaust heat pumps is that, at steady state (i.e. once the temperature has reached the required temp), all the heatpump does is supply say 2kW to replace the house heat loss, and 'lend' and then recover about 6kW to the air as it (quickly!) passes through the house. In theory. A couple of points arise from that - firstly I expect it will be very painful (in terms of high electricity use) initially getting the house up to the steady state temperature, when the exhaust temp is low (perhaps there are icing issues). Perhaps the 8kW heating elements are used at this time (for a few hours!) to try to quickly get to the steady state temp and into the (theoretically) efficient operating regime. Another point is that it's implicit in the theory that air entering and exiting the house is under very strict control, and not entering or leaving by gaps/flooboards/windows/letter boxes and any other leaks.