Seasonal settings on a gas boiler

Beeblebr0x

I have a system boiler. Is there any benefit in adjusting the seasonal settings when I also have a HW tank thermostat and a room thermostat in the hall?

MyRealNameToo

In most cases no; what sort of changes were you thinking of making?

Lorian

Depends what it's set to (it controls the temperature of the water going to the radiators and the cylinder)and what temperature your cylinder stat is set to. 

Beeblebr0x

Lorian said:

Depends what it's set to (it controls the temperature of the water going to the radiators and the cylinder)and what temperature your cylinder stat is set to. 

The HW is set to 60°C for washing on the cylinder stat. The boiler control is set to the winter setting. 

Lorian

What model boiler nd what number on the dial is it set to.

There might be a light chance of making it a bit more efficient if it's a condensing model.

Also how quickly do the rooms warm up in the mornings on a cold day in winter?

Beeblebr0x

Vaillant ecotec plus 415, running 9 rads, so probably under powered. It's on the highest (winter)  setting. The rooms can take up to 45/60 mins during depths of winter.

The gas usage of 14000 kWh is high for a couple living in a 1930s semi, solid walls but modern double glazing.

Scot_39

Turn the radiators flow temps down if seperate, and turn them on 10/20/30 min earlier in depth of winter if need be - might produce cheaper heating results - especially in autumn / spring - when you wont need full radiator powers to maintain room temperatures.

Tweak them back up if struggling in depth of winter.

Think about keeping the hot water at least 10-15 degrees above the thermostat cylinder if the boiler allows it to be set independent of thermostat cut off. The heat flow drops to a trickle if the HW loop gets to close to tank target - and some boilers mark / space cycle lengthening heating time.

And if your tanks open vented and low pressure tank fed - I'd think very carefully about setting it as low as 45/50 some might suggest.

Landlords and businesses have to keep storage tanks at 60C minimum setpoints - thats the HSE rules for legionella.

Beeblebr0x

Thank you.

QrizB

Beeblebr0x said:

Vaillant ecotec plus 415, running 9 rads, so probably under powered.

That's a 15kW boiler which should be plenty for 9 rads, unless they're all monsters.

I've got a 15kW boiler and ten rads in my 1950s semi. In my opinion my boiler is oversized and I could get away with a 12 or even 9kW one. Admittedly I've got cavity walls!

Beeblebr0x said:

It's on the highest (winter)  setting.

Mine's currently turned down to less than half. I'll turn it up in winter if I think the house is struggling to get warm.

oldagetraveller1

My Worcester Bosch conventional boiler doesn't have a "seasonal" setting, only the flow temperature for the boiler.

It's 15kW and supplies 9 radiators. Admittedly not all are used at the same time. It replaced a 18kW Gloworm. The installer recommended 15kW based on the number of rads and their size/output.

The boiler flow out temperature is 60degC which is more than adequate to quickly heat the rooms in which the radiators are turned on (for my system).

Contrary to general advice the hot water cylinder thermostat is set to 50degC. Plenty hot enough for my usage without yet coming down with any form of lurgi.

1967 fairly well insulated Semi-detached house. Cavity wall, loft space and double glazed.

FreeBear

QrizB said:

Beeblebr0x said:

Vaillant ecotec plus 415, running 9 rads, so probably under powered.

That's a 15kW boiler which should be plenty for 9 rads, unless they're all monsters.

I've got a 15kW boiler and ten rads in my 1950s semi. In my opinion my boiler is oversized and I could get away with a 12 or even 9kW one. Admittedly I've got cavity walls!

Beeblebr0x said:

It's on the highest (winter)  setting.

Mine's currently turned down to less than half. I'll turn it up in winter if I think the house is struggling to get warm.

Used to have a 13kW Baxi back boiler. Plenty of spare capacity if I wanted extra (or larger) radiators. Now have a 30kW combi which is way overpowered for heating my (late) 1920s semi.

Fitted a heat meter to the pipes, so can see just how much energy is needed to heat the place. Much of the time 6kW through 8 rads+plinth heater is sufficient. Will peak at 8-10kW at start up and drop to just 4kW on tick-over.

Did hit 20kW during the last service, but with an 80°C flow temperature, this is not a normal operating mode.

A 15kW boiler is likely to be plenty big enough for the OP. It would probably benefit from having a few (or all) of the radiators swapped for higher output ones (assuming no micro-bore plumbing). This would allow the property to heat up faster and/or run at a lower flow temperature - If the boiler is eBUS compatible, with the right thermostat, it can automatically modulate the output down depending on demand.