I’m spending a fortune running a heat pump in my build! Please HELP 😫

[-rick-]

Also worth checking that the immersion isn't coming on to suppliment hot water?

[Nick Laslett]

Did the weekly Legionnaires thing get mentioned yet?

 

 

[Marvin]

On 24/11/2025 at 09:26, damspt said:

@Marvin 

How this affects your energy bills

An average household would need to spend £490 per year on heating, hot water and lighting in this property. These costs usually make up the majority of your energy bills.

You could save £0 per year if you complete the suggested steps for improving this property’s energy rating.

This is based on average costs in 2024 when this EPC was created. People living at the property may use different amounts of energy for heating, hot water and lighting.

 

My doesn't show those kWh per year for heating and hot water for some reason

Hi @damspt

 

£490???  That would be impressive!

f

If I remember correctly my my ASHP uses about 30 watts per hour on standby. So 30 watts times 24 hours times 365 days is .. er 262 kWh per year. 

 

Hot water say 2kWh per day is 730 kWh.

 

All other electrical equipment is not included in the EPC calculation.

 

So 262 plus 730 is 994 times average 25pence per kWh is £248 per year

Standing charge 19p per day say £70

Lighting - 6 5 Watt bulbs 10 hours per day £11kWh - say £30

 

Total £348 Plus VAT 17.40

 

£365 electricity bill with no heating!

 

So  about £130 for the heating per year after VAT.

 

 

 

[Ferdinand]

On 22/11/2025 at 10:44, damspt said:

@marshian i have no idea the temps of each single room, only have 1 thermostat in the lounge. It feels colder in our main room, baby bedroom ( which both are upstairs ) and i guess the lounge which has french doors and a view to a field

Just on this point, get 2 or 3 of these cheap £10 min/max things to measure temperature and humidity. They cost little, and can be used anywhere.

I use one to keep an eye on the drying of my washing for example, which I do in the shower cubicle with a dehumidifier in winter.

The only thing is do not put them where they may fall on the floor; they do not bounce very well.

There are lots of different sorts. This is an example not a recommendation. I buy several then gradually break them over 4 or 5 years.

https://www.amazon.co.uk/HOTUT-Thermometer-Hygrometer-Temperature-Humidity/dp/B0DS25WWL8/
 

[-rick-]

These are better, include bluetooth so you can use an app to track all of them at once.

 

https://www.amazon.co.uk/ThermoPro-Thermometer-Bluetooth-Hygrometer-Temperature/dp/B0BTSW9JGT?crid=1AQOSJR7HAEBD&sprefix=thermopro%2Bbluetooth%2Caps%2C73&sr=8-15&th=1

 

3 for £22

 

Bluetooth means the batteries don't last as long so think about rechargeables once the included* batteries drain.

 

*Pretty sure they come with batteries but it doesn't say that clearly and I can't remember for the ones I got. It's one AAA per unit in any case.

[ectoplasmosis]

On 25/11/2025 at 11:37, -rick- said:

These are better, include bluetooth so you can use an app to track all of them at once.

 

https://www.amazon.co.uk/ThermoPro-Thermometer-Bluetooth-Hygrometer-Temperature/dp/B0BTSW9JGT?crid=1AQOSJR7HAEBD&sprefix=thermopro%2Bbluetooth%2Caps%2C73&sr=8-15&th=1

 

3 for £22

 

Bluetooth means the batteries don't last as long so think about rechargeables once the included* batteries drain.

 

*Pretty sure they come with batteries but it doesn't say that clearly and I can't remember for the ones I got. It's one AAA per unit in any case.

 

I have a load of these around the house, they work very well. The phone app is very convenient, with graphs over time etc.

 

They come with crappy AAA batteries that last a couple of months; replacing with decent quality alkaline AAAs lasts ~6 months for me.

[Beelbeebub]

I have those sensors, they are pretty good for the price. The app can be a bit janky at times but they outperform way more expensive ones and don't come with a ton of bloat and cloud services. 

[damspt]

@JohnMo Hi everyone, I completely forgot about this topic as eventually I saw that many people were spending much more money than me, I'm only spending between £100 and £150 in this weather while I see people spending over £200/£300 which is crazy. 

I have a new issue, this H20 and H62 error came up yesterday and house has been cold and no hot water, I need to shower my son asap. I've cleaned the filter as seen in the picture but still not working. Radiators have been bleeded, some of them no hissing and no water coming off. What else should I do? Please help

[ProDave]

Your system has lost it's water pressure.  One of the plumbers will be along to tell you how to top it up.  In the mean time post as much as you can of the plumbing around the system particularly anything with something resembling a valve etc.

[JohnMo]

1 minute ago, damspt said:

house has been cold and no hot water, I need to shower my son asap.

Flick on the immersion for hot water.

 

Looking at the state of the filter/strainer, your system is full of crap.

 

If you have zero pressure in system it will not bleed.

 

But top-up water to get around 1 bar on the gauge you show. Then switch off power to heat pump, this maybe needed to reset the error code. Switch on and see if cleared. If so it should start up.

 

If pressure has dropped again tomorrow you may either have a leak or you heat system expansion vessel has failed.

 

 

 

 

[damspt]

3 minutes ago, ProDave said:

Your system has lost it's water pressure.  One of the plumbers will be along to tell you how to top it up.  In the mean time post as much as you can of the plumbing around the system particularly anything with something resembling a valve etc.

I will tomorrow, currently doing a night shift. Thank you for the quick reply!

[ProDave]

On 24/11/2025 at 09:35, damspt said:

This looks like your fill loop.  If that is a pressure gauge there, open the two black valves at the end of the silver hose looking thing until the gauge reads about 1.5 bar then close them.  Then try resetting the fault on the HP control panel

[damspt]

1 minute ago, JohnMo said:

Flick on the immersion for hot water.

 

Looking at the state of the filter/strainer, your system is full of crap.

 

If you have zero pressure in system it will not bleed.

 

But top-up water to get around 1 bar on the gauge you show. Then switch off power to heat pump, this maybe needed to reset the error code. Switch on and see if cleared. If so it should start up.

 

If pressure has dropped again tomorrow you may either have a leak or you heat system expansion vessel has failed.

 

 

 

 

Thank you for the quick reply, currently working a night shift. Will try tomorrow.

Before I left home, i've turned the switch which i think it's the immersion for hot water but radiators were still very cold althought the live usage on octopus app was showing more than 4000w, so I told wife to turn it off since it's not warming up the house. When she turn the switch off, she said something sparked around the switch, so not sure.

 

I am not sure which one I need to turn to top-up water, tomorrow will take a couple pictures. When saying "switch off power to heat pump" do I actually turn it off in the meter box or just turn it off in the thermostat? 
 

[damspt]

3 minutes ago, ProDave said:

This looks like your fill loop.  If that is a pressure gauge there, open the two black valves at the end of the silver hose looking thing until the gauge reads about 1.5 bar then close them.  Then try resetting the fault on the HP control panel

Both valves? okey dokey, will try tomorrow! Damn, I love this forum. People are so kind and helpful, unfortunately I'm not skilled enough in any of these topics as I would love to help people like this

[JohnMo]

9 hours ago, damspt said:

When saying "switch off power to heat pump" do I actually turn it off in the meter box or just turn it off in the thermostat

Turn off the isolation switch outside by heat pump. Leave it off for a couple of seconds and switch back on. Or if the controller is on its own power supply, switch that off and on again. Doing both will not hurt anything.

 

9 hours ago, damspt said:

octopus app was showing more than 4000w

Makes sense, immersion are generally 3kW so that plus any other loads in the house. 

[-rick-]

45 minutes ago, damspt said:

Before I left home, i've turned the switch which i think it's the immersion for hot water but radiators were still very cold althought the live usage on octopus app was showing more than 4000w, so I told wife to turn it off since it's not warming up the house. When she turn the switch off, she said something sparked around the switch, so not sure.

 

Sounds like this switch is for the immersion. It wont heat up the house but will give you hot water. If the immersion was drawing 3kw when your wife flicked the switch off a small spark inside the switch is not terribly unusual.

[damspt]

@JohnMo turn both valves and let pressure went up to 1.5 as you can see in pic and reset the system. still showing same error h20.

[JohnMo]

18 hours ago, damspt said:

Radiators have been bleeded, some of them no hissing and no water coming off

Did you finish this after topping up system pressure?

[damspt]

35 minutes ago, JohnMo said:

Did you finish this after topping up system pressure?

yes, wife did yesterday but I just did it again after you mentioned and upstairs they all hissed and came out water which is good i guess. Downstairs they didn't hiss but water came off. I've done a reset once again but still same error code.