Problem with new Intergas HRE 18 OV not heating radiators properly

[sxturbo]

It's in the settings, sounds like it may be range rated on the central heating circuit.

I had a similar issue on my intergas but the other way round, central heating was fine but the hot water took forever.

Turned out the installer was just trying to be a bit too clever and range rated the boiler down on hot water demand.

Really you need someone clued up on intergas systems.

 

[DP]

Reading the post, go back to basics. Boiler works ok for hot water heating so boiler to cylinder operation is good.
For heating boiler creeping along. I would be checking what temperature the boiler is producing to heat the rads. If boiler flow or return shows overheat, is circulation issue. If boiler output temperature now is low, then boiler parameters.

is the pump wired to the boiler so that boiler controls the pump?

Boiler is just a big kettle. It does not know what it has to do, just heat the water and then controls direct the flow where you want it to go. Think logically.

 

[Geoffuz]

Hi all, thanks for the replies.
The parameters are exactly as the manual describes. The only thing i did was raise the temp to 80 from 75, but that's not done anything.

I've had the heating on now for 2 and a half hours and water and heating on now for half an hour and if i grab the flow pipe straight out the boiler i can grip it for a good 3 seconds before it gets too hot to hold. The return pipe is cooler as you'd expect.

I did think about directly wiring the pump to the boiler as i have a redundant drop of cable running between the two, but I surmised it wouldn't make a difference. Maybe i should try it

 

[CBW]

Grab the flow pipe on the heating side of the 3 port, feel if that’s as hot.

 

[Geoffuz]

Grab the flow pipe on the heating side of the 3 port, feel if that’s as hot.

Yes, the same temp.

I should add, this situation existed before i changed the pump. I swapped it to rule the old pump out.

 

[BlueLoo]

Boiler return stat knackered?

Put a thermometer on the supply pipe when using the boiler for heating HW.

Your temp should be close to what you set it as.

 

[CBW]

Does the return at the boiler have an isolation valve? Is it open?

 

[Geoffuz]

Boiler return stat knackered?

Put a thermometer on the supply pipe when using the boiler for heating HW.

Your temp should be close to what you set it as.

Okay i will try that and come back.

Thanks.

 

[Geoffuz]

Does the return at the boiler have an isolation valve? Is it open?

I'm not sure, I'll have a look in the manual and report back.

Cheers

 

[DP]

The return temperature will be as expected. If the return valve was closed, heating pipe out of the diverter would be cold too.

Geoffuz, by touch and feel, check the temperature of pipe out of the boiler, on heating side of the Motorised valve and inlet to the radiators

Then check return to boiler and see if the radiator pipe ( returns ) are the same

With heating and hot water on, check the flow and return temperature at a radiator
Compare thus to flow and return pipes at the hot water cylinder

post your findings

BTW, the pump is normally wired to the boiler and boilers have permanent power supply. When the demand is removed from the boiler, the boiler runs the pump to get the HE temperature down by running the pump which will not be happening if pump is hooked up to the boiler demand

See terminal 3 is not used and you are using the a Y plan
I would be using the terminal 3 as the power source for the timer and the valve

 

[Geoffuz]

Hi DP. Thanks for the info.

I checked the pipe temp out the boiler; on heating pipe just beneath the 3 way valve (it is on heating only at present) and at the first fully open rad feed (bathroom) and the temps were very similar. I did the same for the returns and it was the same story - albeit a lower temp generally as you'd expect. I also checked the last rad on the loop before it goes back to the boiler and the same applied, although there was a general temp drop of i'd estimate, a few degrees.

For the record, things are properly hot now where the trvs haven't shut the rads down, but it's worthy of note that whilst things got warm in an hour this morning, to get to what we would consider proper operating temp, has taken nearer five hours.
At no point has the boiler noticeably modulated, with the exception of when I put the water on when it flared up a while then shut down for a minute, then returned to what i'm calling tickover.

I tried the room stat direct to the 230v and 24 side of the boiler, but it didn't like it. My stat has 3 wires, one of which goes to the 3 way valve via the control centre. Without this the boiler and pump ran, but the valve didn't actuate.

I wasn't aware you could wire the valve and timer direct to the boiler. What would be the advantages of that over the current setup?

My dad's dropping my infrared thermometer off tomorrow so i'll be able to gather more accurate data then I hope.


Thanks again

G

 

[DP]

With all trvs open, expect the temperature difference to 20 degrees or thereabouts including the flow and return to the cylinder as well as the flow as no return at the boiler.

What temperature is the boiler running at

Infrared thermometer is hit or miss, better result with contact or clamp

 

[Geoffuz]

Morning all.

Interesting development. True to my guess that it's the boiler running at tick over is the problem, I've just fired it up from cold, put a piece of masking tape round the flow pipe straight out the boiler so it helps my infrared thermometer get a good reading (sorry, I have no clamps), left it for ten mins and all im getting is circa 40 degrees.

This cant be right can it?

Thanks

G

 

[BlueLoo]

Not nessesarily.

Have you actually asked it to get hotter than 40c? Stupid question i know but still, stupid things happen.

If you have (via the boiler settings) then either something is stopping it by design and a good read of the manual might highlight a knock-back or frost mode or something.
Or, something is duff, like the boiler return stat.

I'd look for the obvious 1st, then go though it with a process of elimination.

Don't know if you can change or check the boiler stat yourself.

 

[Geoffuz]

Hi, Blue. It's set to hit 80 degrees which it probably does after 5 hours
I'm likening it to boiling a large pan of water on my littles gas ring on my hob i. e. I will boil eventually, but takes an age.

There are no settings that differ from those factory ones shown in the manual, so assuming it should work out the box, i can only conclude there's a fault.

It's been an interesting process, but it looks like I'll have to get Intergas out to take a look now unless anyone has any other ideas

Thanks everyone

G