@ldnajt Yes it can, but why would you? If a heat pump system is designed properly, it will work properly and supply substantial savngs and good paybacks. Designed badly, you wish you never had one. It is either or.

@jdee I can help, but I think it may violate the forum terms, check with Mars.

I suggest you tackle the issue the other way around @jdee

First explore the market and get an idea of what GSHP you'd like. Then contact the manufacturer direct and enquire what installation contractors they have in your area.

I had the opportunity to visit Kensa GSHP manufacturers at the far end of Cornwall a few months ago. Discussions with the design team were most useful. Their range of five products is based on a well engineered compressor to achieve optimal efficiency. So the HPs themselves may look no more exciting than a fridge, but you do at least know that all your money has gone into the crucial internal mechanism!

Kensa do all the calculations for their potential customers. This is not left to the Installers. So you have nothing to lose by making contact at the earliest moment.

They will require two main sets of information from you:

• location, which enables them to consult the geological maps for your area
• house EPC and SAP score which tells them how much heat they need to generate

Don't worry if you don't yet have enough information on the latter. They can advise you about appointing a surveyor, certified to PAS 2035, who will produce the required data. If you pay for that separately, then the document becomes your property and you can send it to other potential suppliers too.

@heacol, please feel free to post. I’m actually curious to hear how a GSHP can cool in the summer.

Posted by: @jdee

Hi, I'm basically looking for a GSHP installer and seek to learn about others' experiences of GSHP technology.  I live near York.  My ideal would be to install a system that can heat the house in the winter and cool it in the summer.  I have fairly good techincal undersandings and I understand how such a system needs to be put together.  I used to be very practical, but now have a health problem that curtails what I can do.  All the best, Jon

It is relitivly easy and very cheap to cool with a GSHP, you have install a heat exchainger, and a couple of pumps and a controller (if the unit you have cannot cool, the better European units can). When cooling is required, just run the 2 pumps, and the heat is removed from the house and put in to the ground. You must be cairfull not go below the dew point or you will get puddles on the floor. It does not work that well with radiators but will work well with under floor and fan coil radiators.

Unless the cooling load is very large, this passive cooling methode works well, if it is high, then active cooling with the compressor is required. This is a bit more complicated but not usually required in this country. The heat rejected to the ground, will raise the temperature of the ground, increasing the performance of the unit during the whinter.

As with any heat pump, it either works very well and is very cheap to run, or it is expensive to run and does not work well. If it is designed and opperated correctly, it will work well. You do need good equipment that will controll the heating in the property, if there are third party thermostats, you will have high running costs. A well designed heat pump system should be 30-40% cheaper (40-50% with the new capped energy prices) to run than a natural gas system.

We repair a lot of installations with very high running costs and low comfort levels, it is very rairly the fundimental design of the system, it is more often the way the system is controlled and piped that causes these problems. In most cases, a couple of days work will correct installations for best possable performance.

Posted by: @heacol

When cooling is required, just run the 2 pumps, and the heat is removed from the house and put in to the ground. You must be cairfull not go below the dew point or you will get puddles on the floor. It does not work that well with radiators but will work well with under floor and fan coil radiators.

How is the air extracted/removed from the house and put in the ground? Do you need vents?

@editor The air is not removed from the house, the cold water from the ground collector is circulated through the central heating system, cooling instead of heating. The heat removed is stored in the ground for later use. This can be done with an air source, but as I said, care must be taken with the dew point.

@editor

Because the temperature about 1 metre below ground level is fairly constant in the region of 8C to 10C, if the water is pumped through one side of a heat exchanger, and the heating system water through the other side of the heat exchanger, then the heat emitters in the home will be cooled rather than heated. But as Brendan states, if you cool the heat emitters too much you will get condensation forming puddles.

@heacol I am happy to have two methods of heat exchange within the house, radiators for heating in the winter, and a heat exchanger to cool air which is then circulated into rooms in the summer.  Tat way there are no dew point issues.  The underground heat sink/source would be warmed in the summer and cooled in the summer.  That way the system would work better than a system that is just used as a heat source in the winter.  It's only a matter of some valves opening and closing to allow each mode to operate.  I need a supplier who knows the planning and implementation details.

@heacol 

I believe that Kensa offer cooling, as an add on option.  The Vaillant Geotherm mini (2.5kW heat) has it in by default I believe, so "just" requires software to enable it.  In general, the "free" cooling requires a third heat exchanger inside the heatpump box, which bypasses the compressor when a 3 port valve is operated.  In this way, 2 water pumps alone must operate for the system to cool.  Somewhat surprisingly, Kensas and that Vaillant are not inverter units - I think this is largely due to most R&d going into air conditioners, a close cousin to ashp.  Gshp are the "Mercedes" of heatpumps - clunky old tech, but robust, last forever.

For best operation, you likely need underfloor heating, or very large radiators, or lots of insulation, or as you say glycol/water->air.  If radiators, 2-pipe works better than the really old 1-pipe system, which relies on local convection loops for operation - these don't really happen when cold water is passed around the system.  Given the expense of GSHP, I would expect any old radiators to be replaced with larger ones though.

Boreholes will be much more successful for cooling than slinkies or straight pipes in trenches, as the local ground will remain cool until when it is needed - late summer, by which time shallow slinkies will be less effective.  Slinkies usually don't go deeper than 1.2m due to safety issues.  Depending on the local geology, sometimes ground water is extracted from one borehole, deposited into another.  More generally though, very deep boreholes are drilled, 100m+ into the ground - this generally requires access by large machinery - have you an idea of the site? 

Do you know your yearly heat demand, or instead your peak power requirement?

Appreciate you want names of installers near York... can't help you there!  Maybe if you become convinced Kensa or some other specific manufacturer could help, you can contact them for an installer list. 

@jdee PM me if you want to discuss it.