Hot water new boiler

lil_old_me

Thanks. I have emailed them and a few minutes later they emailed back! Next Friday - it definitely appears to be the boiler as its not getting over 60 degrees

unclebulgaria

I haven't read it but has anyone mentioned the tank stat may not be correct?
You could turn the tank stat up higher and have look at the temp again? It may not be accurate.

keystone

lil_old_me wrote: »

I was not sure what was asked before. I just turned the boiler on - to the maximum on the dial. This is apparently 85 degrees C. I just turned boiler on, left for 10 mins and then got my husband to open the air vent which is just before the cylinder (eg its water straight from the boiler) and the water was only 60 degrees. Surely this means boiler faulty?

But you are not measuring the temperature at/on the outside of the pipe as suggested! Apparently 85 degrees doesn't mean it is. Measuring the temperature of the water as you release it from the vent allows it time to cool. Sorry to say this but you are not doing useable measurements. Yes there will be a temperature gradient across the wall of the pipe but if its 22mm pipe as it leaves the boiler and 22mm as it enters the coil in the tank then the temperature fall through the pipe wall will be the same and you will get a meaningful relative result. You balance a CH system the same way by measuring the temperatures at boiler flow/return and each radiator flow/return on the outside of the pipework.

Cheers

Edit: and please could you also do the other measurements previously requested.

lil_old_me

Thanks. I did try to measure the actual pipe temperature but it was not very hot and I was not getting useable readings when I did this. Pipes were recently replaced, I think they are 22mm from the boiler and 22mm as it enters the cylinder

lil_old_me

When I turned the tap on after 30 mins being on maximum (85 degrees C on the boiler itself) it came out around 60 degrees. I do not want it on full all the time

keystone

lil_old_me wrote: »

When I turned the tap on after 30 mins being on maximum (85 degrees C on the boiler itself) it came out around 60 degrees. I do not want it on full all the time

My heart sank initially when I read this but then I read it again and found that, probably inadvertently, you have given a clue to the root of the problem. If you do not give the boiler time to heat the tank then the water in the tank won't get up to temperature. Its not instantaneous and from cold you will have to allow the boiler to run for at least 90 minutes to heat the average HW cylinder to the point where the water temperature coming out if the tap is what you want it to be ie 60 degrees. Its not that the tank is losing temperature nor that the boiler isn't working its that you just ain't giving it a chance.

Your last sentence just says you aren't running your system properly as I suggested way up the thread.

Cheers

T_T_2

As above, you are demanding the performance of a combi boiler from a system boiler.

lil_old_me

I normally run the boiler for 90 mins. We only use it for hot water, not showers on anything. So normally 90 mins - dial on boiler 3/4 way round. It should be more than 50 degrees

keystone

lil_old_me wrote: »

I normally run the boiler for 90 mins. We only use it for hot water, not showers on anything. So normally 90 mins - dial on boiler 3/4 way round. It should be more than 50 degrees

90 minutes per day or 90 minutes in the morning before you get up or what? Do you allow the cylinder stat to turn the boiler off once it decides that the cylinder is up to temperature or do you just make an arbitrary decision that it can now be turned off.

I am going to ask this little lot one more time and please believe me this is for the very last time.

1. What is the temperature taken on the outside of the flow pipe from the boiler when it has been operating for five minutes at full setting. I am not asking what it should apparently be at that setting from the manual. I am asking what it actually is.

2. What is the temperature taken on the outside of the flow pipe into the heating coil in the cylinder and what is the corresponding temperature on the [STRIKE]flow[/STRIKE] return out of the cylinder. Measurements taken straight after step 1.

3. What is the temperature at the output pipe where it exits the cylinder to the taps when the cylinder is up to temperature and you have run the hot tap until you get hot water from it and what is the temperature taken on the outside of the pipe close to the hot tap.

The actual temperature of the water as it exits the tap or can be drawn out of the air vent near the cylinder isn't of any interest to me.

The reason to ask this (and this must be the third or fourth time) is to attempt diagnosis whether the problem you perceive may lie in the boiler, cylinder or pipe runs.

Cheers

lil_old_me

Thanks keystone. Just been able to check back in. I am going to get husband to take readings requested tomorrow and report back