Actual water temperature from the tap?

[puntloos]

So my ASHP is set to 52C (but of course the cylinder will fluctuate between say 46 and 52 based on heating cycles)

 

My question: what is a reasonable temperature to expect coming from a bath tap in the farthest corner of a house, about 15-20m worth of (in theory at least) well-insulated pipe?

 

Assuming 52 - can I expect 51.9? 50? 46?

 

The water coming from my bath tap is *just* warm enough to be called comfortable bath, so I imagine it's about 38C? Surely if I actually got 52C it would be bad? painful even? Or just very sweaty very quickly?

[Gary68]

Mine is set to 48C and I can just about hold my hand under it continuously, so it sounds like you are a lot lower than that if the bath is just warm enough, at 50C you get burnt in 5 mins.

 

Also depends where the temperature sensor is in your tank if its not towards the bottom a lot of the tank won't be at 52C

[SteamyTea]

Temperature is a measure of mean, free path, molecular velocity.

Sound a mouthful, but it is just the average we measure.

When something is heated up, some molecules will travel, or vibrate, slower, while others will travel or vibrate faster. 

Those faster ones are at a higher temperature than the slower ones, with the bulk, being in the middle.

 

So while the heat source may be set to 52°C, there will be times it is a bit higher, and times it is a little cooler.

That is before density change is taken into account. Though with a UVC this is not so important compared to a vented cylinders.

[dpmiller]

is there not a protective thermostatic valve on the hot tank?

[puntloos]

14 minutes ago, dpmiller said:

is there not a protective thermostatic valve on the hot tank?

I was wondering about this. I don't know, but even if it is it would be set a bit low I'd say? 

 

7 hours ago, Gary68 said:

Mine is set to 48C and I can just about hold my hand under it continuously, so it sounds like you are a lot lower than that if the bath is just warm enough, at 50C you get burnt in 5 mins.

 

Also depends where the temperature sensor is in your tank if its not towards the bottom a lot of the tank won't be at 52C

This is good info for me. With this indeed I'd estimate my actual temperature at tap is more like 43-45 (depending on actual heat of the cylinder at any given time). I'll probably get a proper thermometer, as a modern nerd I only have these surface temp devices that don't wokr too accurately on anything other than skin..

[SuperJohnG]

Is it a mixer on the bath? 

 

Turn the basin and bath to hot and see 

 If they feel the same. If it is a mixer on the bath chances are someone has had the tap off it and it's not been replaced right. 

 

I've 52 degrees set on my tank, the bath (uninsulated pipe- there is very little point insulating hot pipe) is say 10m of pipe away, it is too hot to hold my hand under really at full hot.