Posted by: @kev-m

Funny you should say that, mine has settled down to a 3-4 times an hour cycle. I'll post some graphs on my other thread tomorrow.  

Hi Kev,

Do you know if it is cycling because it is right down at the bottom end of its operating range, or because the indoor temperature has become too high?

One of the problems with heat pumps is for best operation then should run continuously at the lowest water flow temperature, but of course they have a minimum loading below which they cannot run.

How is the temperature control performing?

I look forward to seeing your data.

Nor sure; the indoor temp and flow temps are not that far apart now (23/30).  

Posted by: @kev-m

MCSCERTIFIED.COM "https://mcscertified.com/wp-content/uploads/2020/07/Heat-Pump-Guide.pdf"

All,

I came across this while browsing for information on heat pump design (as you do).  It might be of some interest here and you would think MCS resistered installers would follow it.

The way I see it, one of the problems is that it is a guide and not necessarily a requirement. The other thing is who is checking the installations?

Some installers will no doubt have the attitude that if we can charge for something, but only do the absolute minimum, who is to know. Most customers will not have a clue whether their system has been correctly installed and commissioned, until they start having problems when the cold weather arrives.

I know I'm an old cynic.

@derek-m Not a cynic. But unfortunately it comes through from the manufacturers who are only interested in selling a box without any cum-back- hence development of the buffer tank installation. They are not interested in training people to do it properly, as it is too difficult and costly to change people from what they are used to doing. In my view it is very short-sighted and you, the end user ends up paying the price.

It tarnishes the reputation of the product and industry and is difficult for the few that do it properly, as the majority do not.

@heacol 

Brendan, if what I'm doing is the right way to run the system (and I'm reserving judgement because I'm a bit of a cynic too!) then it's going to be a huge leap of faith for most people. Havings the heating on 24/7, not using thermostats having almost cold radiators are the complete opposite of most peoples' experiences with boilers.  Most people just won't believe it will work or think it will be really expensive.  Maybe some installers are taking the easy way out by folllowing the path of least resistance and giving people what they are used to. 

Having said that, my installer didn't tell me to use the ASHP it like a boiler, I did that on my own!  They didn't tell me not to though, although did they tell me weather compensation was the best setting to use and left it set it up like that.

The other thing you have to remember is that forums like this are a self selecting group of fairly knowldgeable and enthusiastic people who are normally willing to listen and change.  Convincing us is quite easy.  Unfortunately that's not representative of the general population.

@kev-m You are absolutely right, and I expect you to be a cynic.

"The other thing you have to remember is that forums like this are a self selecting group of fairly knowldgeable and enthusiastic people who are normally willing to listen and change. Convincing us is quite easy" and it has taken me 3 weeks to convince you to try something with everybody shouting me down.

You can see the uphill battle I have, in fact, in my view, heat pumps, just like condensing boilers are a mis-selling scam perpetuated by industry, the training bodies, the manufacturers, the certification bodies and all the associations, including MCS. If they were doing their jobs correctly, we would not be in this situation, you must remember that the RHI has been going for 10 years and nothing has been learnt.

A heat pump is not a boiler, They are completely different, a boiler changes the state of energy, a heat pump moves energy, they do not heat a property, they add heat energy to a space, resulting in a warm house. The analogy I always use is, cars and aeroplanes are both means of transport, you can drive an aeroplane down a road, but it does not work very well. You can treat a heat pump in the same way as you tread a boiler, but it does not work very well.

@kev-m This cycling may be caused by a low system volume, however 3-4 times an hour is not excessive and will not damage the unit.

I have been trying (and failing, impossible on my phone) to keep up with the chatter in here. As someone who is actively monitoring my electricity usage and currently the house is warm and costs are low, I am hesitant to make any changes, but I'm all for making sure I have the optimum set up, not just for low running costs, but also to ensure the pump isn't being overworked. 

It would be really if there could be a simple summary article written at all? Reading between the lines it sounds like our heat pumps should be set to weather compensation mode?

I'm not entirely sure if my pump has this mode, we moved into our house last summer but were given no instructions / walk through about the pump or the control panel. Google suggest it does have, we have a LG Therma V.

As it stands, our thermostats are the trigger for heating the house, when/if the temp in a zone drops below 18 / 20 degrees (depending on time of day) that sends the signal to the pump to start moving heat into our rooms. At the moment I think this is working fairly well for us. My hesitancy on making changes is that our costs are fairly low at the moment, and if I start changing things, costs increase, and forget how to get the settings back to how they currently are.

To be fair, for all I know my unit may already be set to weather compensation I really don't know. but I don't think it would be given we don't have an outdoor sensor and the thermostats are the trigger.

Dumb question - would weather compensation mode increase the running costs? 

Posted by: @dant

I have been trying (and failing, impossible on my phone) to keep up with the chatter in here. As someone who is actively monitoring my electricity usage and currently the house is warm and costs are low, I am hesitant to make any changes, but I'm all for making sure I have the optimum set up, not just for low running costs, but also to ensure the pump isn't being overworked. 

It would be really if there could be a simple summary article written at all? Reading between the lines it sounds like our heat pumps should be set to weather compensation mode?

I'm not entirely sure if my pump has this mode, we moved into our house last summer but were given no instructions / walk through about the pump or the control panel. Google suggest it does have, we have a LG Therma V.

As it stands, our thermostats are the trigger for heating the house, when/if the temp in a zone drops below 18 / 20 degrees (depending on time of day) that sends the signal to the pump to start moving heat into our rooms. At the moment I think this is working fairly well for us. My hesitancy on making changes is that our costs are fairly low at the moment, and if I start changing things, costs increase, and forget how to get the settings back to how they currently are.

To be fair, for all I know my unit may already be set to weather compensation I really don't know. but I don't think it would be given we don't have an outdoor sensor and the thermostats are the trigger.

Dumb question - would weather compensation mode increase the running costs? 

 

Good morning Dan,

If my memory serves me well I do believe the LG Therma V has the capability to operate with weather compensation enabled, if you wish I can look into it for you.

I agree with your sentiment about change, 'if it's not broke, don't fix it', but just as a car engine will still work when it is not correctly tuned, tuning it will make it much more efficient.

The first thing to do is see how your system is set up, and then see what improvements may be necessary. If you would like to supply more details about your system, I should be able to guide you through a few simple checks to ascertain how your system is performing.

@derek-m 
Thanks. 
What would be useful for me to share with you? I don't have any schematics etc. 

Posted by: @dant

@derek-m 
Thanks. 
What would be useful for me to share with you? I don't have any schematics etc. 

You should have been provided with instruction manuals for all the equipment when you purchased the property, but you can download most information from the Internet these days. The type of information that is useful is the following-

The model and size of your ASHP.

The size (m2) and type of your home.

The level of insulation and any heat loss calculations you may have.

A list of the equipment (thermostats, valves, pimps etc) giving manufacturer and model.

Type of heat emitters (radiators and/or UFH)

To check if weather compensation is activated on your system, in the top left hand corner of the LG controller screen, there may be a small house icon displayed, if it states 'AUTO' underneath this icon then weather compensation is activated.

hi @derek-m sorry for the delayed response, we've both been struck down by a cold 

• You should have been provided with instruction manuals for all the equipment when you purchased the property, but you can download most information from the Internet these days. The type of information that is useful is the following-
• The model and size of your ASHP

LG Therma V, 7kW (7000 watts)

• The size (m2) and type of your home.

Semi detached barn conversion, downstairs in the main is open plan. Approx. 129.5 sq m. see below approx. floor plan attached.

• The level of insulation and any heat loss calculations you may have

We’re in a new barn conversion, unfortunately the builders have not handed over any heat loss calculations, they have told us that the level of insulation is above building standard however.  

• A list of the equipment (thermostats, valves, pimps etc) giving manufacturer and model.

Downstairs we have UFH controlled by 4 zones, each zone has its own Emmeti thermostat. Upstairs we have radiators / towel rail in each room, all controlled by one thermostat on the landing.

Under the stairs (boxed in) are all the valves for the UFH again the builders never shared any information about these with us.

• Type of heat emitters (radiators and/or UFH)

Downstairs it is all UFH, controlled using zones, we have 4 zones downstairs. Upstairs we have radiators / towel rail in each room, all controlled by one thermostat on the landing.

• To check if weather compensation is activated on your system, in the top left hand corner of the LG controller screen, there may be a small house icon displayed, if it states 'AUTO' underneath this icon then weather compensation is activated.

Had a look at the LG Controller screen and there doesn’t appear to be a house icon displayed.