Is 5kw ASHP too small?

[ruggers]

On 06/12/2022 at 07:10, HughF said:

you only need one of them, not two as specified by most installers. 

I wasn't aware of them, everyone always say fit 2. Are they a serviceable part because there's a lot riding on them working if it's fit and forget and you get a power cut in 8 yrs time on freezing day. TBH I can't think of the last time there was every a power cut in 15 years, but we do get -5°C periods every year for a few days/week. 

On 06/12/2022 at 07:10, HughF said:

 

On 06/12/2022 at 13:55, ProDave said:

Are you serious about valves to dump the water out of your system of it freezes?

 

I just mixed an inhibitor / antifreeze with the water in mine at a level that should prevent it from freezing to -10.  Job done.

Did you just mix regular antifreeze used for something else and fill your whole system with it, so it's in your radiators and all pipework?

 

I was hoping not to include any inhibitor in a new install and apply VDI 2035.

[ProDave]

27 minutes ago, ruggers said:

I wasn't aware of them, everyone always say fit 2. Are they a serviceable part because there's a lot riding on them working if it's fit and forget and you get a power cut in 8 yrs time on freezing day. TBH I can't think of the last time there was every a power cut in 15 years, but we do get -5°C periods every year for a few days/week. 

Did you just mix regular antifreeze used for something else and fill your whole system with it, so it's in your radiators and all pipework?

 

I was hoping not to include any inhibitor in a new install and apply VDI 2035.

It was a cheap inhibitor / antifreeze that screweys sold a few years ago, intended for central heating systems and mixed at 25:1 would give frost protection to -10

[HughF]

5 hours ago, ruggers said:

I wasn't aware of them, everyone always say fit 2. Are they a serviceable part because there's a lot riding on them working if it's fit and forget and you get a power cut in 8 yrs time on freezing day. TBH I can't think of the last time there was every a power cut in 15 years, but we do get -5°C periods every year for a few days/week. 

Did you just mix regular antifreeze used for something else and fill your whole system with it, so it's in your radiators and all pipework?

 

I was hoping not to include any inhibitor in a new install and apply VDI 2035.

When was the last time you changed the thermostat in your car?

[SteamyTea]

10 hours ago, HughF said:

When was the last time you changed the thermostat in your car?

Mine was done 3 years ago because the seal had gone.  Noting wrong with the actual thermostat.

That is on a car that was then 11 years old and about 140k miles.

Edited December 21, 2022 by SteamyTea

[ruggers]

On 20/12/2022 at 22:10, HughF said:

When was the last time you changed the thermostat in your car?

Seems irrelevant, but 6 years ago. When the stat fails on the car its usually in the half open position and stops the engine every fully warming up or takes a very long time, it doesn't blow the engine. If it fails closed you'll have a nice warm engine and cold cab.

 

The anti freeze valves are a pressure relief system that stops your 4 grand bit of kit being damaged in the rare instance theres a power cut and the outside air temperature is 3°C or less.

Thats the only reason I asked if they are servicable. These things tend to never need to activate and if they haven't, but in 5, 6 8 yrs time they need to but have sized isn't good. I've never seen them to make a judgement on whether they would fail closed or not.