Low Loss Header leak

[ashthekid]

Hi,

 

I have a relatively new ASHP setup which is approx 2yrs old and at the beginning of last year I started noticing a drop in pressure which I was having to top up every month or so which didn’t bother me as I couldn’t see if there was a problem anywhere on the setup. 
I have since discovered a very small slow leak from the low loss header which would explain the pressure dropping and maybe why the whole heating system isn’t working as efficiently. 
 

I’m wondering what people’s thoughts are on this? Do I get it re-welded or replaced like for like(although I support it was built on site with the amount of welding I can see on it) or removed or replaced by a different setup?

Here is a photo of it attached. 
I’ve just been quoted over £1000 for a replacement(labour 3hrs & parts) which I thought was quite punchy considering a LLH is only around the £200-350 price point. 
 

 

[JohnMo]

It's just a bunch of fitting soldered together. I would start to ask yourself do you really need it, its a rubbish design (well not really designed), its just about a close coupled tee, without the what looks the incorrect dimensions, as its way to short.

 

I would look at your heating system and advise what you have

 

Heat source, type and size in kW

Heating system - UFH or radiators or both, how many loops and or radiators

How many thermostats in operation? And an assessment of do you really need them

 

I suspect your CoP will be very poor.

[ashthekid]

I was told it was kind of essential on a system as large as this to boost performance and efficiency whilst also balancing out the flow rate when there is more than one circuit. 
It definitely looks made up rather than off the shelf which I wish I'd identified before as the original quote from the plumbing company stated a Culm DN25 low loss header which I believe is a brand selling off the shelf units.

 

So our only source of heat is with our Hitachi Yutaki S 8.0 split system ASHP which I was told could handle a peak load of 13.5kW ASHP.

UFH throughout downstairs and upstairs via 4 manifolds (2 up and 2 down). 400l hot tank. 6 plumbed towel rails. This covering a 5 bedroom, 4 bathroom home. 19 thermostats covering approx 380sqm. We have a large open plan kitchen lounge dining area which has a glass wall and bifold on one side so I know we have some serious heatless from there as well as some big air gaps around some oak trusses which I know doesn't help. The whole house is run on electricity so no gas or oil.

[ashthekid]

[ashthekid]

[JohnMo]

That LLH looks nothing like anything Clum sell.

 

5 minutes ago, ashthekid said:

19 thermostats

Sorry that's bonkers, how can you have 19 room spaces in a 5 bed house? Do some room have more than one thermostat?

 

I would be better looking to simplify the whole system.

 

Are your running costs ok or a big?

 

 

[JamesPa]

55 minutes ago, JohnMo said:

That LLH looks nothing like anything Clum sell.

 

Sorry that's bonkers, how can you have 19 room spaces in a 5 bed house? Do some room have more than one thermostat?

 

I would be better looking to simplify the whole system.

 

Are your running costs ok or a big?

 

 

Someone involved in the design must have had shares in Honeywell!

[ashthekid]

@JohnMo Yes it does sound bonkers but there lots of extra rooms like 2 offices, Tv room, playroom, utility, 2x lounges, snug, hallway, landing etc so it very quickly added up. It's a new build within 200yr old walls so quite an unusual setup.

 

Running costs are a lot more than I calculated that's for sure and during the build all the energy costs were constantly creeping up.

We only have electricity and over there last two years we have spent approx £700 per month during the winter months and this summer that came down to £200 per month, probably mainly due to the benefit of solar panels, albeit a small array(10 panels) which I wish I had made larger now of course.

 

And I'm really annoyed now that I did not notice the LLH was not the intended Clum one that I had agreed to.

[SteamyTea]

3 hours ago, ashthekid said:

We only have electricity and over there last two years we have spent approx £700 per month during the winter months and this summer that came down to £200 per month

Do you have some hourly data for your consumption, your summer usage seems very high.

[Lofty718]

19 thermostats is absolutely wild with a heat pump. You could probably remove every single thermostat and run the heat pump on weather compensation (how it should be) and your bills would be reduced by 30% at least

 

My 5 bed 4 bath house is less than 200 sqm and feels pretty spacious, yours at 380sqm house must feel like a palace lol

[JohnMo]

First before you do anything else analyse what actually happening with the heat pump. Are you getting long run time consistently (more than about 15 mins) or are you getting some rapid on off cycles. or something different?

 

I would look to rationalise the number and size of zones to just a couple.  The issue you will have are

 

Heat pumps need flow rate

Any heat source needs somewhere to dump the heat generated. Think the current setup is good for neither.

 

You currently have so many zones, that when only one or two are calling heat they are all quite small capacity. 

 

If you are happy with current bills and house comfort just repair what you have. If you would like to reduce bills also, I would look to engineer the LLH out of the system, by getting rid of most the thermostats, running a more open system (ideally one zone, maybe 2)

 

 

 

[ashthekid]

To be totally honest I am probably running the ASHP as a traditional gas boiler in that I'm heating up the DHW tank from 5am to 10am and then again from approx 2-4pm, off for the peak times on the Agile tariff(4pm-7pm) and then back on for a couple of hours 7-9pm.

UFH I having coming on at 5am pretty consistently all day until 11pm which is when I drop the temp down below 20 degrees.

I don't have all zones on though. I would say on average I always have about 6 zones totally switched off and during the summer I didn't have any UFH switched on for the months of May/June/July/August.

 

 

 

 

 

This is the 2023 data I took from my OVO account before switching over to Octopus's Agile tariff last week.