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@editor Ive just emailed the CEO, Mars, so lets see what happens.
House-3 bed partial stone bungalow, 5kW Samsung Gen 6 ASHP (Self install)
6.9 kWp of PV
10kWh DC coupled battery
Blog: https://thegreeningofrosecottage.weebly.com/
Heatpump Stats: http://heatpumpmonitor.org/system/view?id=60
Thanks for raising this. We’re really sorry we haven’t been active in this thread, our priority has been to work directly with the customer and our technical team to get this resolved as quickly as possible.
This issue remains a top priority for us. Our engineers are continuing to investigate and implement a fix, and we’re working closely with our service partners at Robert Heath to make sure it’s resolved as soon as possible.
We know how frustrating this has been and genuinely appreciate your patience while we get it sorted.
@editor lol if I was the priority I would hate to be lower down the list.
House-3 bed partial stone bungalow, 5kW Samsung Gen 6 ASHP (Self install)
6.9 kWp of PV
10kWh DC coupled battery
Blog: https://thegreeningofrosecottage.weebly.com/
Heatpump Stats: http://heatpumpmonitor.org/system/view?id=60
Posted by: @bontwoody@editor lol if I was the priority I would hate to be lower down the list.
You'd think, given the public profile of this thread and the presence of a representative from @mixergy that they would be pulling out all the stops to get this resolved TODAY.
Unfortunately this just reads as a shocking indictment of extremely poor customer service and warranty. It's not difficult to get a replacement tank and engineer on site to replace a faulty part.
Not acceptable to be left without hot water for nearly a month (will be a month on Monday).
Samsung 12kW gen6 ASHP with 50L volumiser and large radiators. 7.2kWp solar (south facing), Tesla PW3 (13.5kW). Net Zero
@bontwoody, I completely agree.
I have to say, the level of support here has been really disappointing especially from a brand as established and reputable as Mixergy. I genuinely can’t understand why a replacement unit wasn’t dispatched and installed within days, and why you have a working cylinder that has been abandoned in your hall. This should have been treated as a priority, not something that drags on for weeks.
I hope you’ve requested compensation, because this level of service is frankly unacceptable. You paid for a premium product, and it’s only fair to expect a premium level of support. As part of our own retrofix project next year, Mixergy was a product we were seriously considering, but this experience has given me real pause for thought, and I think we'll take a different route.
You mentioned you’re using the instantaneous water heater for showers... does that mean you’ve been left without hot water in the kitchen and the rest of the house as well?
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@editor fortunately we have a boiling water tap in the kitchen. 😁
I had a very courteous and supportive reply from the CEO so let's see what happens next week.
House-3 bed partial stone bungalow, 5kW Samsung Gen 6 ASHP (Self install)
6.9 kWp of PV
10kWh DC coupled battery
Blog: https://thegreeningofrosecottage.weebly.com/
Heatpump Stats: http://heatpumpmonitor.org/system/view?id=60
Just an update. The cylinder has now been replaced and is up and running again. Once it was fitted, the technical department were very helpful in talking me through a commissioning problem (my bad!)
Im waiting for them to pick up the old cylinder and then hopefully we shall be wiser as to what went wrong!
House-3 bed partial stone bungalow, 5kW Samsung Gen 6 ASHP (Self install)
6.9 kWp of PV
10kWh DC coupled battery
Blog: https://thegreeningofrosecottage.weebly.com/
Heatpump Stats: http://heatpumpmonitor.org/system/view?id=60
@bontwoody Thank goodness you are ‘back on-line’ so to speak - that must be a great relief! Do keep us posted on what the old cylinder was suffering from please! Regards, Toodles.
Toodles, heats his home with cold draughts and cooks food with magnets.
So following on from my new Mixergy cylinder replacement, they kindly sent me an indirect cylinder instead of the direct one I was previously using.
It seems likely that I might be able to use the coil to at least preheat the cylinder and maybe top it off with the immersion. However Im having some difficulty in getting it to work. I dont have the Mixergy Heat Pump control box but am just trying to use a schedule to preheat the cylinder.
The schedule seems to start as predicted but after a few bursts just stops, as in the graph below:
My FSV values are:
3011 Use(Hysteresis)
3021 50C
3022 0
3023 5C
3024 5C
3025 95 mins
3026 3 hours
3031 Use
3032 95 mins
3033 0
3041 Not Use
Any ideas anyone? Thanks
House-3 bed partial stone bungalow, 5kW Samsung Gen 6 ASHP (Self install)
6.9 kWp of PV
10kWh DC coupled battery
Blog: https://thegreeningofrosecottage.weebly.com/
Heatpump Stats: http://heatpumpmonitor.org/system/view?id=60
I think the mixergy coil is quite small, they sell an add on circulator and phe for heat pumps. I don't know how Samsung's algorithm works but is it possible coil is near top, once it's heated the water immediately around that's it, given a relatively low ft from the hp?
4kW peak of solar PV since 2011; EV and a 1930s house which has been partially renovated to improve its efficiency. 7kW Vaillant heat pump.
@jamespa That was one of my thoughts too, but looking at the flow and return temperatures that doesn't seem to be the case. The coil is about midway down the tank.
I also thought that perhaps because I dont have the mixergy heat pump control unit that the desertification pump probably isn't on.
Surely if these were the issue though the flow and return temperature would be close and why does it stop after just 3 attempts?
House-3 bed partial stone bungalow, 5kW Samsung Gen 6 ASHP (Self install)
6.9 kWp of PV
10kWh DC coupled battery
Blog: https://thegreeningofrosecottage.weebly.com/
Heatpump Stats: http://heatpumpmonitor.org/system/view?id=60
What are the actual flow temps, the scale seems to be hidden.
Close flow and return indicates insufficient heat transfer.
Do you have the destrat pump. If so a good idea to run it somehow!
4kW peak of solar PV since 2011; EV and a 1930s house which has been partially renovated to improve its efficiency. 7kW Vaillant heat pump.
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