@econonsense - that doesn't sound right at all. Can you give more details - size and make and model of heat pump, installation details, heat loss calculations etc - and we might be able to give you some advice.

Hi @econonsense  Your plea for help is heard!

What you're stating here is very similar to the observations I read from a batch of 250 householders who were provided with heat-pumps by the Government, in a Trial called The Electrification of Heat.
That discussion group wasn't available for the general public to read, so you can't see it.
But I suspect we're about to find similar issues in your case.

Please start by giving us basic overview of

• what Heat-pump you've got
• radiators or underfloor heating, and are there thermostatic valves?
• size of Domestic Hot Water cylinder (should be on the label)
• Was it replacing a gas boiler, or what else?
• Was it supplied under any scheme run by local government or similar?
• Approx build-date of the bungalow
• Was any additional insulation installed at the same time?
• roughly where are you in Britain?

Feel free to post a photo of the external unit, or pipes/pump/valves around the hot water tank.

@transparent

Hi Gents, wow those are quick replies! I wasn't actually expecting help, just venting frustration, but I'll take it with thanks!.

It's a Grant Aerona 10.5kw system, I have a 180 Litre Grant boiler ( which they placed in a pressed steel shed in the garden ) There are 10 radiators with TRVS ( with batteries in that allegedly detect people )

Yes it was paid in part by an Eco scheme, I'm in North Wales, the house is old, not sure 1850-1890 maybe.

Yes they insulated all external walls ( on the inside ) with 100mm insulation ( they made an appalling job of this ) they also insulated the loft.

Prior to this I had a gas boiler central heating system which cost around £800-1500 / year.

This system is aiming to be around £4-5000 / year!

@cathoderay I have no idea about heat loss calculations. They said after the install someone would come with a heat sensor and check for cold spots, this never happened.

Cheers

@econonsense - the heat loss is an essential part of the design process, it is used to determine the size of heat pump. I should mention in passing there is controversy over the accuracy of heat loss calculations, as opposed to measured heat loss, but putting that aside for the moment, all installations need to have some form of heat loss. It should be in your paperwork - if, that is, you have any...

@cathoderay Hi I have some paperwork but can't find any reference to heat loss calculations.

I perhaps should have mentioned, they set my system to be always on at 19 degrees.

I have repeatedly contacted the company re the lack of hot water but don't get the courtesy of a reply, hence my looking online for solutions. 

I have 2 log burners so at even further cost I can keep the house warm.

Its the lack of hot water I can't live with.

Cheers

Posted by: @econonsense

↑

I have a 180 Litre Grant boiler

Boiler?

Is this perchance a hot water cylinder, but outside the house due to lack of space inside?

Posted by: @econonsense

↑

There are 10 radiators with TRVS

In general, thermostats shouldn't be fitted when you have a heat pump.

They're required when you have a boiler, in order to turn it on/off according to heat-demand.

But a heat-pump should be running continuously.
The heat-output is automatically regulated by the system adjusting the Flow.
It uses a Weather Compensation curve, based on the design temperature (19°C for you) and an external temperature sensor.

When a heat-pump turns on it uses a lot of electricity.
The compressor has to bring the up the pressure in both fluid-loops before it achieves operational state.

@transparent Hi yes sorry, a 180 litre water tank / heater

I removed all the trv's this morning after some reading, decided its worth a try.

Does the water heater turn off on a timer or when it reaches temp? If its temp regulated, this will explain excessive elec usage, as it never gets to temp unless the ambient outdoor temperature gets to >10 degrees 

Posted by: @econonsense

↑

I have repeatedly contacted the company re the lack of hot water but don't get the courtesy of a reply, hence my looking online for solutions. 

No hot water or heating should be escalated to an immediate reply from the installer. It's outrageous when this happens. Can you please check to see whether the installer is registered with HIES or RECC, and let me know?

I'm equally concerned by your running costs, echoed by others already. We have a 16kW heat pump and use less electricity than that, running the house at 21C. 

@econonsense The chances are that the removal of the TRV’s will result in the valves being left fully open (which with heat pumps is the usual practice anyway as the balancing is done using the lockshield valve on the other end of the radiator) The radiator will now emit more heat - is this your intention at the moment? I would strongly recommend that you use the lockshield valves for balancing as per my article: 

https://renewableheatinghub.co.uk/how-to-balance-radiators-the-role-of-the-lockshield-valve

Regards, Toodles.

@toodles Hi, they balanced the system twice, the first time they had to switch to rads off completely as the ones at the back of the house never got warm.

The 2nd attempt seems better, all radiators get tepid.

I have no intentions removing TRV's, only the hope of saving a bit of electricity! I  will monitor the usage and see if it improves with them removed.

Posted by: @econonsense

↑

I perhaps should have mentioned, they set my system to be always on at 19 degrees.

I take it that is the desired indoor air temperature. If so, it raises a question mark as MCS (the official (though some say clownish) body that oversees heat pump installation standards) require higher design temperatures (21 degrees) in living rooms. Note those are design temps, you can of course choose to run at lower (or indeed higher) temperatures. The point is the system should be designed to be capable of reaching MCS temps (albeit with rare exceptions when the occupier knows what they are doing) all the more so as MCS approved installations are the gateway to most if not all grants. 

Is your installer MCS approved? If they are, it will be plastered all over their paperwork.

Running 'always on' is normal for heat pumps, as you have probably already gathered.  

@editor Hi, are there any settings or changes to the system you can recommend?

I'm a mechanical and  electrical engineer, so I'm confident to try things, however I know little to nothing about domestic heating systems

Cheers