Thank you, great description of what’s going on with the operation of the pump 👍 guess I knew a bit more than I thought, but helps to understand it fully so cheers!
I’ll make sure the air intake is clean from debris and will wrap the pipes with some old towels and bin liners till Engineers come with new insulation.
Ahh yes, I didn’t know the function of the little white boxes. They replaced a couple before they replaced the whole HP with a new one. I’ll test their function is working ok just now.
Ok thanks, what is the purpose of a Constant flow regulator? This one is set to 0.5 bar and connected just beside the green diff pressure valve on the 2nd floor manifold, and then again another one down in the pipes in the Utility.
Thank you, great description of what’s going on with the operation of the pump 👍 guess I knew a bit more than I thought, but helps to understand it fully so cheers!
I’ll make sure the air intake is clean from debris and will wrap the pipes with some old towels and bin liners till Engineers come with new insulation.
Ahh yes, I didn’t know the function of the little white boxes. They replaced a couple before they replaced the whole HP with a new one. I’ll test their function is working ok just now.
Ok thanks, what is the purpose of a Constant flow regulator? This one is set to 0.5 bar and connected just beside the green diff pressure valve on the 2nd floor manifold, and then again another one down in the pipes in the Utility.
If you are referring to the valve with the black adjuster located between the flow and return pipes connected to the manifolds, that is a bypass valve. It is designed to open if the pressure difference between the flow and return exceeds the pressure setting.
If the pump pushing water to the UFH circuit is running, but all the solenoid valves for the UFH loops are close, then there is nowhere for the water to flow and the water pump would cavitate (that's a word you can Google). The bypass valve is therefore designed to open if the pressure gets too high, and allows flow to continue. In practice the water pump should not be running if all the solenoid valves are closed, but you could have a situation where only one of the solenoid valve is open, and the flow on that particular loop is adjusted quite low, so could cause problems for the water pump if the bypass valve was not installed.
@derek-m Yep got it makes sense, protects the system from overloading when no zones are flowing but the pump on the off chance is pushing flow.
Onto the pumps, there’s 2 and I’m guessing one for each manifold as I’m guessing there’s two separate pipe circuits that flow to their respective manifolds?
Both of these are set to Max, whether that’s right for this system who knows! Engineers always say they need to be on max. 😂
Next are the brass vents with red caps, 5 in total on my system, I’ve heard just the other week I’m meant to vent at least once a month? Never been done in 5 years till now 😂
Lastly there’s 2 brass connections on the same pipe, one a flow setter and the other just ports. Guess the flow setter is regulating the water coming from the ASHP to the tank? But what’s the point in the brass connector after it, and there’s so many bends in the pipes when surely it can be minimised with straight piping?
Welcome to the World of domestic heating, the more bits that you can fit, the more you can charge the customer.
The brass units with the red caps are probably to vent any air out of the system. If there is equipment that you are not certain about Google the manufacturer and model number which should provide some details. Anything that you are not certain about then just post details.
I do believe that the system at your home could have been designed to be much simpler and more efficient, but I assume that you are not in a position to make any physical changes, so the best we can do is make adjustments.
Inside the heat pump unit, located outside, is a water pump, which pushes the water into your home. Since I cannot clearly see where all the pipes go to and from, I will have to make some assumptions which you will be able to correct if I am wrong. Once inside your home the feed from the heat pump should be piped to the actuated valves, one of which will feed the warm water to the heating coil inside the hot water cylinder, and the other to the UFH manifolds, which may possibly be via pumps.
The pumps are required to move the water around the system, and also produce sufficient pressure to overcome gravity. You should be able to download the manual for the pumps, which should provide details of how they can be operated. The pump pushing the water up to the second floor will need to produce more pressure than the one for the first floor.
To get the best efficiency from an ASHP system with full UFH, you require sufficient flow to maximise the heat energy transfer, whilst operating the system at the lowest LWT that meets the heat demand. A fairly constant flow of water at a temperature of say 30C, will provide the same amount of heat energy as an intermittent flow of water at 40C.
I would suggest that you sketch out the layout of your system, identifying the location of pumps and valves etc. so that we can see how the system has been designed, and how it may be improved.
@derek-m That sounds right, builders will have charged the MOD hella’ dosh for building this estate I bet!
Brilliant these are great little tips that will keep me busy the next couple weeks of leave.
You’re right that can’t really do anything majorly physical, but if it’s something minor or small part that can easily be swapped out and then swapped back in when moving out that’s fine. 👍
But I’d imagine a lot of this will just be adjustments with what we have sadly.
That’s brilliant idea with the sketch, that may take some time so I get it right though haha
I appreciate all the info and advice you’ve shared with me, thanks Derek!
@derek-m Perfect thanks! Yep my HP is on the list so will give that a read through
Also typed in product code for different parts and found another extensive manual for the FTC2, currently making way through it and checking what DIP switches they have mine set on, as noticed a Boost heat or COP function while heating DHW or how regular the legionnaire cycle happens. That will be little efficiency gains right there
@derek-m Perfect thanks! Yep my HP is on the list so will give that a read through
Also typed in product code for different parts and found another extensive manual for the FTC2, currently making way through it and checking what DIP switches they have mine set on, as noticed a Boost heat or COP function while heating DHW or how regular the legionnaire cycle happens. That will be little efficiency gains right there
I'm glad to hear you have joined the 'bedtime reading' team.
Thought I’d jump on and give a little update. So that same week we had a group of contractor going round the estate to find out what is going on. There were families being shipped out to Hotels or being moved to homes in different estates!
Luckily they deemed our house was actually good in terms of things working than the other houses, but agreed efficiency should be a priority as no point paying over the odds. They recommended to the upgrades team that we need another circulating pump to the upstairs manifold, as we are just not getting much flow upstairs (non existent if you look at the flow meters).
They changed me off WC and on exact flow temp…. That was changed straight back 😂
Im now running full WC with stats as limiters 2oC above.
Flow settings are 25oC @12oC outside and 38oC @-2oC outside.
Bought 3 Govee hydro-thermometers to check real life temps and it’s comfy around house maybe even too comfy 22oC mid floor(kitchen and living room and 19/20oC top floor (bedrooms) so could afford to try knock down slightly.
Being with Octopus they sent me out a FLIR cam for a few days to check the house. House is good and apart from some slightly leaky seals at some windows the house is insulated well. Right enough the top floor manifold is open full but some return pipes were cold so a pump probably needed.
Also I joined Octopus new Cosy Tariff, designed for HP owners, 2 cheap rates 20p/KWh at 0400-0700 and at 1300-1600. A peak rate 52p/KWh 1600-1900 and rest of time at mid rate of around 34p/KWh.
On the circulating pumps, I decided to investigate as the ones downstairs at the water tank were all at max 3. 1 is to the return to HP and other for circulation. I changed HP one to low/1 and circulation to mid/2 and noticed no change.
Still about £10-£12 a day this last week when it was cold but we are comfy at least.
Lastly I’ve now noticed that Delta T is very close, how close is too close? They can be like 2oC difference sometimes the same. And the cold weather has me noticed it may be doing defrost cycles quite often, but how many is too many?
Lastly I’ve now noticed that Delta T is very close, how close is too close? They can be like 2oC difference sometimes the same.
An interesting question, and I am sure there will be many opinions on this one, certainly one I would like to get to the bottom of.
My current view [not backed up by any evidence] is that if the heat pump is not fast cycling there is not a problem. I run mine at 3 degC delta and [most] of the time it is running with a very low frequency "ticking" [seemingly] quite happily. When it starts to "fast cycle" I switch it off or raise the flow temperature a bit by offsetting the weather compensation.
