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New radiators installed and system drained - what to do next?
We're renovating our house and as part of that we installed new radiators and a small UFH loop covering 12 m2 in the new extension. The radiators were fully drained first, so all of the glycol that was originally put in when the heat pump was installed is now gone. The plumber is not familiar with heat pumps and said that we should ask the original installers to recommission the system and put the right amount of glycol in.
Now, it's a stupidly cold English June, our heating is off because the radiators have no water in them, and the original installers are taking an age to get back to us.
Is there any way I can fill the system with just cold water and no glycol myself, temporarily, just so the system is up and running while I wait for it to be done with the correct amount of glycol? Or will this run me into problems with warranties and so on? Does the existence of the UFH loop (which was not present when the heat pump was originally installed and has never been turned on) mean that I should just be patient and wait for a professional to look at it all? What would you do in my position?
Can we safely turn on the hot water at least?
(As an aside, it is ridiculous the lack of knowledge about heat pump systems. Surely it's not that difficult for a plumber, who has presumably learnt 95% of the things required to work with heat pumps, to learn the remaining 5%? Anyway.)
ASHP: Mitsubishi Ecodan 8.5kW
PV: 5.2kWp
Battery: 8.2kWh
As noone else has replied and its cold, I will do my best to answer you question :-). As long as you dont get freezing temperatures (and your heat pump is off) it should be fine to fill up your system with water. If you wanted to used glycol you can get a cheap refractometer to measure the level of protection you have given it with the concentration used.
I used to use Sentinel X500 in mine but now I have anti-freeze valves instead.
I can’t say what effect this would have on your warranty though so it would be at your own risk so to speak.
House-3 bed partial stone bungalow, 5kW Samsung Gen 6 ASHP (Self install)
6.9 kWp of PV
10kWh DC coupled battery
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@bontwoody Thanks! Much appreciated!
ASHP: Mitsubishi Ecodan 8.5kW
PV: 5.2kWp
Battery: 8.2kWh
@scrchngwsl, while it's tempting to fill the system and get it running during this cool spell, I would advise against it. Since the UFH (underfloor heating) has never been tested, if you fill the system and there's an issue (through no fault of your own), it will be easy for them to place the blame on you. And since the system hasn't been commissioned, if there is an unseen fault, and your heat pump gets damaged, it probably won't be covered by warranty.
I'd exert pressure on the installers coming back ASAP and finishing the installation. And when they come back to commission the system (I'll be curious to hear what they actually do), make sure you insist that they thoroughly balance both your radiators and UFH. Proper commissioning and balancing are crucial to optimal performance and even heating.
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@editor Thanks for that advice Mars. I finally got them to give me a date next week, which is soon enough that we can survive without heating so won't take the risk of messing something up. I'll be sure to get them to balance the rads and UFH too.
ASHP: Mitsubishi Ecodan 8.5kW
PV: 5.2kWp
Battery: 8.2kWh
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