Ground Source Heat Pumps

lovesgshp

Hi DW.
Have just had this answer back from our engineer after I sent him the information that you supplied. To get the parts locally, would be better for you, than to have them sent from Italy as he suggests.

"OK.
I think the customer has to check the two flexible hoses on the left side of the heat pump starting from the upper one.
probably there is a restriction of the flow there, due to a couple of reasons:
- bad water on the heating circuit
- internal rubber deterioration (we experienced some cases).

Probably they will find the two hoses obstructed. The have to substitute them.
We can supply the original spare parts (Different black colour) or they can buy a non original part locally"

Hope this helps.

JHen

Hi lovesgshp,
I've noticed my expansion tank is less that 1/3 full. How to I go about topping this up and with what.

Also, is it possible to have an evening and day heating temperature setting?

Thanks.

lovesgshp

Hi JHen.
You can top up the expansion tank with just plain water, or if the installer left you some of the coolant mix. Make sure the ground loop circulating pump is running and then remove the valve at the top of the expansion tank and fill to 2/3rds. Refit valve and you should be ok.

With regard to the heating, then you could use the timer, but you only have the option of 1 setting per day. This only reduces the flow temperature to the heating and should not be confused with room temperature.
If you are using rads then the max is 4C, or for underfloor max 2C.
HTH. If you need any more info then let me know.

JHen

How do I know if the glc pump is running - is his when the water/heater light is in and it make the murmuring noise? Do you know what coolant mix I need to buy?

Yes, I was talking about the room temperature . We wanted a day and night setting. Looking at the panel this does not look possible - perhaps I'll need to get some radiator thermostat/timers for the bedrooms.

As usual - many thanks for you help.

lovesgshp

Do you know how to get into the service/installer menu? From that you can operate the manual control of the circulating pump, instead of waiting for normal operation.
For coolant, in your case, just use water, as you will not dilute the mix by any significant amount. If you want the proper coolant, then it will be: "pure propylene glycol" used for air conditioning systems.

If you want to control the heating with thermostatic rad valves, then you must ensure that 70% of the heating circuits are fully open at all times.

beardymarrow

JHen wrote: »

<snip>

Yes, I was talking about the room temperature . We wanted a day and night setting. Looking at the panel this does not look possible - perhaps I'll need to get some radiator thermostat/timers for the bedrooms.

As usual - many thanks for you help.

Reducing the rad return temp by 3deg (option 4.1 in the menu of an IVT) on the timer at night should give you the same end result. We found that as our house is so well insulated so takes ages to cool, and the GSHP takes time to warm a cool house we were better off not messing with that setting, as it didn't save us any money in the end. We just turn the rad thermostat down on the bedroom rads.

frslam

I have been running a Heatpump for the last 7.5 years. It is an IVT HT Plus E7, External 280Ltr Tank (double shell) with Solar Thermal Pipework installed (Solar Thermal not completed yet). I also have a 100Ltr Buffer Tank, all Rooms individually controlled with Underfloor Heating on 2 x floors. In winter time I usually open all upstairs loops fully, hoping that the Temperature difference won't be too great for heat cycle, hoping that it'll make the system more efficient. There are 7 x Loops on each Manifold/Floor. Each floor is approximately 80 sq.metres. I live on the Isle of Skye so can (and often do) experience many weather extremes. My entire house uses about 12,000 kw/h per year incl. cooking, washing machine and everything else. I built the house before the latest Building Regs. came into force (before air tightness/heat recovery etc). I've really enjoyed reading this particular forum, and I recognise some of the info posted. Since my system was installed, I've continually logged Heatpump usage v Electric Meter Usage and continue to do so. I have data for 7.5+ years. I'm a bit stuck though. Everything appears fine, but the Ground Loop Return GT11 is giving a weird reading. it is about 24c, approximately the temperature of the utility room where everything incl. washing machine and tumble dryer is installed. Incoming temp (Loop - GT10) is fine, probably starts cycle around 14c, reducing to 2c at end of cycle. Would love to find out where the Sensor for this (GT11) is installed, could it be a faulty sensor or something else

beardymarrow

frslam wrote: »

I have been running a Heatpump for the last 7.5 years. It is an IVT HT Plus E7, External 280Ltr Tank (double shell) with Solar Thermal Pipework installed (Solar Thermal not completed yet). I also have a 100Ltr Buffer Tank, all Rooms individually controlled with Underfloor Heating on 2 x floors. In winter time I usually open all upstairs loops fully, hoping that the Temperature difference won't be too great for heat cycle, hoping that it'll make the system more efficient. There are 7 x Loops on each Manifold/Floor. Each floor is approximately 80 sq.metres. I live on the Isle of Skye so can (and often do) experience many weather extremes. My entire house uses about 12,000 kw/h per year incl. cooking, washing machine and everything else. I built the house before the latest Building Regs. came into force (before air tightness/heat recovery etc). I've really enjoyed reading this particular forum, and I recognise some of the info posted. Since my system was installed, I've continually logged Heatpump usage v Electric Meter Usage and continue to do so. I have data for 7.5+ years. I'm a bit stuck though. Everything appears fine, but the Ground Loop Return GT11 is giving a weird reading. it is about 24c, approximately the temperature of the utility room where everything incl. washing machine and tumble dryer is installed. Incoming temp (Loop - GT10) is fine, probably starts cycle around 14c, reducing to 2c at end of cycle. Would love to find out where the Sensor for this (GT11) is installed, could it be a faulty sensor or something else

Hi frslam,
Sounds like you've got a great, well set-up system there.

The GT11 sensor is under the insulation on the pipe that goes out of the GSHP to the ground loop (you'll see the thin black wire leading under the insulation). It's inside the GSHP. It'll be on the right hand side of the unit. On mine it's just cable tied on, so you could easily take it off and put it in a mug of ice water to test it. If it's faulty, should be an easy replacement. You could also swap GT10 and GT11 (the sensor themselves are the same) to check for definite it's the sensor itself, and not the main circuit board.

A false high GT11 temp won't cause a problem as such, or any alarms, but you should get it sorted, as you'll not be able to detect any real problems (GT11 under limit, being the main one) so if you did get a real problem, you could cause some expensive damage before you knew about it.

If you're a data freak (I am) you'll enjoy a StatLink (http://www.husdata.se/), as you can log all the sensors 24x7 and graph them etc. It's absolutely brilliant, and has helped me tweak settings to achieve better efficiency.

frslam

Many Thanks for that, another issue is the Hot Water temperature. I think I read somewhere the maximum default setting for Hot water was 54c or 55c. No matter what Temp. I have as setting, whether its the default 51c or whether i change that to 52c or 50c, it seems to want to heat the water to 54c. It's a strange one, maybe another sensor acting strangely. Was considering resetting to Factory default settings to see if that sorted anything, but I'm worried in case the language would also change to Swedish or something, then where would I go to change Language settings before re-programming. I am actually very happy with the System, living in a 160sqm house in the North of Scotland, Temperatures all around my house of a constant 21c and the system costs less than £800 per Year for all Heating and Hot Water needs. Again, many Thanks for the info.

beardymarrow

frslam wrote: »

Many Thanks for that, another issue is the Hot Water temperature. I think I read somewhere the maximum default setting for Hot water was 54c or 55c. No matter what Temp. I have as setting, whether its the default 51c or whether i change that to 52c or 50c, it seems to want to heat the water to 54c. It's a strange one, maybe another sensor acting strangely. Was considering resetting to Factory default settings to see if that sorted anything, but I'm worried in case the language would also change to Swedish or something, then where would I go to change Language settings before re-programming. I am actually very happy with the System, living in a 160sqm house in the North of Scotland, Temperatures all around my house of a constant 21c and the system costs less than £800 per Year for all Heating and Hot Water needs. Again, many Thanks for the info.

Hi, this is normal. There are two things going on with the DHW temp. The first is that the off temp is decided by the gt9 return sensor, not as you might assume by the gt3 DHW temp sensor. The second is that there is hysteresis set (4 degrees by default but I changed mine to 2). So on mine if the DHW target is set at 50 (which it is), it comes on when the gt3 sensor hits 49 and goes off when the gt9 hits 51 (gt3 itself is a couple of degrees higher than that). Hope that puts your mind at rest.