Hi Bridget,

This is a simple check that you can perform.

On top of the wall mounted grey cylinder is an automatic air bleed valve, with a red plastic cap.

I suggest that you loosen the red plastic cap and listen for air being expelled. If air does come out then check the water pressure and refill if necessary.

It may be best to not fully tighten the red plastic cap.

Also Derek, my system kept losing pressure as a valve was not working inside the indoor unit. I could see the drop in pressure on the controller screen... Thankfully that's fixed now.

actually looking at Bridget's home screens there is a change in pressure: 1.5 in the morning then 1.4 in the afternoon of 13th

Hi all

noise problem not resolved.  I have managed to get the disinfection to work though so that's progress.  Am going to work on the schedule + reheat setting next for hot water.  Used the thermostat last night as directed to reduce the temperature to 18 degrees from 12am to 6am and that worked (though 6 am came with the sound of the Airing cupboard preparing for take-off 😀).

I've been round and felt the radiators and looked for closed valves.  All are similar temperature except for the radiator in the bedroom next to the airing cupboard which is warmer than the others.  That one is currently not fully open.  I also have a radiator in another bedroom which didn't work properly with the oil fired system and unsurprisingly still doesn't with the new one.  It gets a bit warm at the top but not the bottom.  The radiators on the system are a real mixture.  Some are newer with valves with numbers.  Others look pretty old and don't seem to have a valve.  The installers all knew this and came on site and viewed the system before installation.

@derek-m I have a mobile wireless thermostat but not a thermometer.  I don't know if that would do what you need.

the WD curve is maintaining a comfortable 19 degrees so is working well at the moment, thank you.  The thermostat is set above this (except when I did what was recommended to cool things during the night when I set it at 18 degrees as advised).

@derek-m I've had a look at the red cap.  It was already loose.  Unscrewing it further didn't seem to do anything.

My water pressure is currently 1.3.  I think it does fluctuate a bit.

thanks again all.

@bridgetjohn 

As you don't have a thermometer you may have to resort to the 'British Standard Hand' method of temperature measurement.

What I suggest is that you hold the pipe containing the black bypass valve, to check for temperature changes. If you hold this pipe approximately in the centre between the two outer pipes, and see if there is a noticeable change in temperature when your system goes into noisy mode. If the temperature of the pipe increases, then this would indicate that water is flowing through the pipe via the bypass valve, which should not be the case if the system is operating correctly.

Water should only flow through the bypass valve when the flow through the radiators is restricted by TRV's or closed valves. A further reason could be that when the water pump goes into high flow mode, the pressure increases to a level that also opens the bypass valve. A higher pressure bypass valve may therefore be necessary, though before changing this valve you should have your radiators correctly balanced.

@derek-m Thank you, I'll try that.  

In the meantime I wonder if the noise dropped a bit after opening the red cap on top of the grey tank.  Its not quiet but potentially sounds less like a washing machine.

@heat-pump-newbie

Just set my schedule + reheat only.  Can I ask if this looks about right to you please?

and then there was a confusing setting for reheat point - it was at 48 so I didn't touch it.:

Eco was on 45 and comfort on 50 by the way so I just left that alone.

Hysteresis is at 10 still.

thank you

Posted by: @bridgetjohn

@derek-m Thank you, I'll try that.  

In the meantime I wonder if the noise dropped a bit after opening the red cap on top of the grey tank.  Its not quiet but potentially sounds less like a washing machine.

Hi Bridget,

Loosen the red cap and then gently tap the valve body to ensure that it is not stuck.

Hi @bridgetjohn 

You only need to specify the Eco and Comfort temperature once each on the schedule. The tank will heat up to Eco starting at 03:00 and won't stop till it gets there. Once done it'll switch back to space heating. Again at 14:40 it'll start heating to Comfort and ditto.

I would say you should lower the Reheat. Mine's on 40 with hysteresis at 10, so when the tank temp drops below 30 deg it will reheat to 40 deg. With it set at 48 deg the system will start reheating when it falls to 38 deg, which might be a bit too often. It depends how much hot water you use and how big your tank is, but I would say lower it then see if it runs out too frequently !

Posted by: @bridgetjohn

@derek-m Thank you, I'll try that.  

In the meantime I wonder if the noise dropped a bit after opening the red cap on top of the grey tank.  Its not quiet but potentially sounds less like a washing machine.

Hi Bridget,

Have you resolved your noise problem yet?

Feedback is always useful.

@derek-m Hi, no not yet I'm afraid.  I think it reduced a bit after following the tip with the valve on top of the holding tank.

I think there is more air to come out of the system, the bathroom towel rail needs attention too.  I suspect your tip with the pressure valve is also relevant, the pipes need lagging and the system balancing.

I think our next step is, armed with all this info to go back to the installer.  

I'll let you know how I get on.  Thanks.

Hi

so we had a service engineer out from the installation company today.  He said that the noise is due to the water having to go from 22mm into 15mm pipes and having a single pipe system.  If we switch off the towel rail, it forces water to flow back through the overflow valve.

He did an air purge and said there was no air in the system - the noise literally comes from water rushing round the pipes and that towel rail.

He has lagged the pipes in the airing cupboard.

Does that make any sense?

He seems to be implying that the ASHP can't work with a single pipe system and we may need to change it.  If that's the case, why were we approved for fitting one on the assessment visit?

Thoughts welcome.