Baxi back boiler

[Gillimarie54]

Hi
We have a very efficient Baxi back boiler about 15 years old.
The radiators all have thermostatic valves.
No room thermostat. we have a timer for CH and WH in the kitchen. These are auto, all day, always on and off.
we can set water separately from heating in the summer. we have a cylinder in our airing cupboard. This also has a simple on off immersion heater switch but no other controls. We have rarely used this switch.
I was setting the little dial high/low on the boiler to the lowest setting. That means hot water not so hot. And I read that was not good.
So with no temperature on this boiler dial and no ability to control the water and heating temp separately, what is the best position setting for it?
I’ve set the valves on about 3.5 which keeps rooms warm enough. Unused rooms are in frost protection setting.
I’m just trying to be as efficient as possible. Especially in view of rising gas prices. Our boiler is regularly maintained and serviced by a great local company. They’ve been coming for over 40 years!!
I can run the heating very effectively with the dial set to just above low, but the water isn’t hot enough apparently for safety.
we have one electric shower and one which comes from the hot water with a pump.
anybideas for settings?
thank you
Gillian

 

[Ihavenojob]

It sounds as if you have a gravity system, not very efficient, but very simple and reliable. You are not going to increase the efficiency, so just set the boiler thermostat dial to where you are comfortable. Best bet would be trying to insulate the property as best as you can. I had an old Potterton Kingfisher on a gravity system, in winter the boiler stat was cranked right up, in summer it was below 1 as the water had no other control.

 

[Gillimarie54]

Thank you. That’s reassuring to know that we are doing the best we can. The house is insulated. Shell cavity wall insulation and loft insulation. I think we could do with a top up in there. There are newer standards. But it’s quite deep. We are replacing UPVC windows as necessary for newer ones.
I’m very careful and read the meters regularly to get a good idea of use. We are with octopus dvd they are brilliant and send a ‘bill’ daily if you want it!!
So I’ll go on doing my adjustments and know that there are no other ways to be better.
Thank you.

 

[Ihavenojob]

So I’ll go on doing my adjustments and know that there are no other ways to be better.

There are always things you can do, but they will entail expense and upheaval (floors up, pipework re jig, system re wiring), best leave the system as it is and then upgrade when it eventually dies.

 

[MeldrewsMate]

We have a very efficient Baxi back boiler about 15 years old.

I've split your post into sections, my comments in red...
Was the backboiler changed 15 years ago? Did your usual company do it? For the last 20 years all new boilers have had to be 'high efficiency' unless an exemption could be achieved. Whilst there are high efficiency backboilers around it sounds like yours isn't one of them.
Effective, as in heating up quickly and being reliable, is not the same as efficient.
The radiators all have thermostatic valves.
Good, set them to what suits you.

No room thermostat.
Hence the doubts raised earlier. This also suggests that your present backboiler is well over 20 years old.

We have a timer for CH and HW in the kitchen. These are auto, all day, always on and off.
We can set water separately from heating in the summer.
Which means you more probably have a fully pumped system.

We have a cylinder in our airing cupboard. Excellent...put some more lagging on it. An old quilt will do on top of the foam/jacket.

I was setting the little dial high/low on the boiler to the lowest setting. That means hot water not so hot. And I read that was not good
It's not. Do you have a cylinder thermostat? If so set it to 60C and your boiler 'stat (the boiler dial) to just about 2/3 of maximum. This will ensure you get the water hot enough to kill off legionella, and the boiler will not fire unnecessarily (short cycling).

So with no temperature on this boiler dial and no ability to control the water and heating temp separately, what is the best position setting for it?
As above, the TRVs will limit room temperatures, but the addition of a room 'stat will reduce your bills.

I can run the heating very effectively with the dial set to just above low, but the water isn’t hot enough apparently for safety.

Any ideas for settings?
Yes. Insulate the hot water cylinder (more, more, and more!). Insulate the hot pipes all through the airing cupboard.
Get a room 'stat.
Get a new (high efficiency) boiler and upgrade the controls (and pump).
If your 'man' has been coming for 40 years plus then you'll be getting on a bit yourself, so this new boiler will save you gas (or whatever expensive stuff comes through the pipes in the near future), and will probably see you out
Did I mention adding more insulation?

 

[Gillimarie54]

Wow. Great thank you!
Our house is a Wimpey semi with extension. Extra bedroom bathroom cloakroom and conservatory. Circa 1970s. We moved in in 1978.
There was already a back boiler and I think that’s why it was replaced ok. The fire had stopped functioning optimally and we decided to replace. Siting and piping a different type of boiler would have been tricky.
In fairness, it works incredibly well. It’s only cost us yearly service and had ignition electronics replaced once about three years ago.
It heats up the rooms very quickly once on.
Getting on? What cheek!! Lol. We are fairly recently retired from our careers, but still in our 60s. We were married very young!! 46 years ago.
Cylinder has no separate temperature setting. Not that I can find and I did have a good look. It could take another jacket. Good point. It’s just got one of those plastic tie on things.
lots of food for thought in your reply. The first back boiler was truly old when we replaced it but still working really well. It was a Baxi too.
They seem to be extremely reliable and I had got it working using low level temp but then I found out about the dangers with the hot water. So I’ve turned it up substantially. I really appreciate everybody taking trouble to reply. I think I understand the pros and cons now of this boiler. Changing will be an upheaval but I expect we’ll find somewhere to put the new boiler. Or indeed, go for something completely different. There’s new technology emerging all the time.
Thanks again. Gillian

 

[Hugh Jaleak]

Firstly, you need to heat the Hot Water to a minimum of around 65 °C to kill off any possible Legionella Bacteria. Hotter wont hurt, but it's a waste of energy when you'll only be adding cold water to the hot to be able to use it!

High Efficiency Gas boilers have been required to be fitted since 2005, possible you squeezed in one of the last SE Back Boiler units before the rules changed, but in your situation I think its a classic case of if it isn't broken, dont fix it. Keep what you have until it gives up the ghost completely or parts are no longer available. Serviced properly and looked after, it may well last many more years, and it is often debatable whether the savings in gas achieved from a new boiler ever outweigh the cost of the installation.

Cannot advise exactly without seeing the setup, but from what I can glean, some small alterations may benefit you in the medium term. Conversion to what is known as a 'C Plan' system may not take much, and would give basic control over the Hot Water Temp., ditto fitting a Roomstat to control the Central Heating may also benefit you.

Upgrading to a 'Y' or 'S' plan would involve more work, (pipework alterations and electrical works), but would give superior control over heating and hot water.

Lastly, insulation is key. Its not about the cold getting in, it's the heat getting out!

 

[Tricky-Dicky]

One pipe above your hot water cylinder (the draw off pipe) can lose a lot of heat due to 'single pipe circulation'. Ensure this pipe is well insulated.

 

[Gillimarie54]

I will look into insulation of the draw off pipe and retro fitting the other useful controls.
Many thanks for giving me your suggestions.
I will definitely put the easy wins into practice.