gas pressure - consumption

[holmslaw]

Is there a direct relationship between bolier gas pressure and consumption.

Recently had the gas pressure reduced on my boiler from 10.5mB to 4.8mB and the heating seems to be working ok. Can I expect to see a 50% reduction in my gas bill.


Boiler is a Baxi 511RS about 25 years old.

 

[doitall]

Why was it reduced and which idiot did it.

 

[holmslaw]

Any replies from people who are not know nothing idiots most welcome.

 

[Deleted member 105431]

the data badge has a specific range of pressures the boiler can work on, I doubt 4.8mb is within that range so whoever done it is retarded as doitall says. If you want to save gas buy a modern boiler instead of an old relic.

 

[holmslaw]

Any replies from people who are not know nothing idiots most welcome.

or *******.

Many Thanks

 

[Watchmaker]

I should think that a reduced boiler gas pressure should result in slightly less gas useage but, was this done arbitrarily or, for some specific repair/alteration?
The experts will, no doubt comment but, my limited knowledge would query whether injector sizes were changed at the same time, as I understand that the boiler manufacturer/designer would "match" the recommended pressure to other components, possibly the injector, within the boiler. To continue to use the boiler, with such a big difference in the gas pressure would, I think, bring about other problems, ie, possibly flame colour, height etc, and my view would be that it would be prudent to get impartial professional advice.

 

[Deleted member 105431]

Is there a direct relationship between bolier gas pressure and consumption.

Recently had the gas pressure reduced on my boiler from 10.5mB to 4.8mB and the heating seems to be working ok. Can I expect to see a 50% reduction in my gas bill.


Boiler is a Baxi 511RS about 25 years old.

You are obviously a tight arsed ******. Go ahead and play with your boiler all u like

 

[D_Hailsham]

Recently had the gas pressure reduced on my boiler from 10.5mB to 4.8mB

Boiler is a Baxi 511RS about 25 years old.

The Baxi 511RS is a range rated boiler. The highest setting is 17.5mB (19.8kW) and the lowest 4.8mB (10kW). Your original setting of 10.5mB is about 15kW. So the person adjusting the boiler was not doing anything wrong, just reducing the output to the manufacturer's minimum.

Why this was done is another matter. What reason did the person give?

As far as consumption is concerned, a boiler set to 10kW will consume two-thirds the gas of a 15kW per minute. Whether your gas bill will reduce will depend on how well the boiler copes with the heating requirement of the house. If it is no longer giving out enough heat, so the house does not reach the temp set by the thermostat, the boiler will run continuously and you will consume more gas.

The other factor is radiators. If your rad total 15kW and you have a 10kW boiler, the rads will never get hot. This may be OK in mild weather but, if the temperature drops to freezing, the house will never get really warm.

 

[holmslaw]

Thanks wachmacer and D Hailsham.

The pressure was reduced because my radiator load is about 32000btu, the lowest setting for the boiler is 34150btu = 4.8mB.

It had been set on 10.5mB which equates to a load of just under 53300btu.

But it does'nt seem to have effected the gas consumption that much, hence the post.

 

[Agile]

Why was it reduced and which idiot did it.

Following the information kindly provided by the learned Lord Hailsham, I would contend that the person who adjusted the burner pressure was acting both professionally and totally correctly in setting the boiler output to a lower power.

The boiler in cold weather would operate continually at 10 kW with its output matched by the radiator heat loss.

It the boiler is set to 15 kW then it will heat up the radiators in say 10 minutes and then go off for five minutes and cycle like that.

Its slightly less efficient but the overall gas consumption is very nearly the same!

Tony

 

[D_Hailsham]

Following the information kindly provided by the learned Lord Hailsham,

RTFM

 

[Agile]

Quintin would probably not know what RTFM stood for !

 

[holmslaw]

Its slightly less efficient but the overall gas consumption is very nearly the same!

Tony

Thought I was going to save loadsamoney.

So it seems the only relevance the gas pressure has (to my situation) is in the time to heat the house from cold.

Also do you think it more economical to run CH 24/7, rather than couple of hours in the morning and 5-6 hours in the evening.

 

[tonybhoy]

Would you boil a kettle 24/7 just in case you wanted a cup of tea?

 

[holmslaw]

Would you boil a kettle 24/7 just in case you wanted a cup of tea?

Is that supposed to be an anology!

An anology of the situation would be an urn contaning a couple of gallons of water - I suppose would you would switch if off after making your cuppa.

I'm sure someone who knows what there talking about will respond.