Bizarre usage of bottled gas - less used to keep house at high temp rather than low temp

Are you sure they were full, about the only way to know is to weigh them?

Are you sure they were empty, about the only way to be sure is to weigh them?

Were they full cylinders when you first moved in? Was the cottage a private holiday cottage or let out to visitors who may have fiddled with the changeover so depleting them equally. Is it in an Isolated location and was left for a long period, someone may have thieved the full ones and replaced with ones not quite empty . Unlikely but what people will do should never be underestimated, I still feel a pang of conscience even nearly 50 years later when we had to give up the tenancy of a shared house as the owners were returning from South America. The agreement meant we should have topped the oil tank up to or over a mark on a sight glass but even the minimum delivery would have taken the level well above, So for a few weeks we filled screwtop bottles with water and dropped them in the filler hole till the mark was covered.

G H

I was there when the first set of cylinders were delivered by Calor. I can only assume that at that time they were full and that the hoses were fully tightened after they were installed.

They were empty in the sense that they had insufficient gas to light the boiler - it went through a repeated lighting sequence and eventually gave up with a subdued "whoof" (and an error code on the display panel) which may have been escaped gas eventually igniting within the combustion chamber after failing to ignite as a jet from the burner - the boiler engineer said that was normal for this type of boiler. Maybe the pressure is enough to light the pilot light and heat the bimetallic cutout to satisfy the boiler's safety logic, but insufficient to light the main burner. What was slightly odd was that there is an automatic changeover valve which switches from the empty pair of cylinders to the full set once the pressure of the empty set drops below a critical level, and that hadn't changed over. If it had, I'd have suspected "no gas" immediately and not called the engineer out. When the engineer arrived he did a gas-pressure test and found it abnormally low and said "if the changeover had been on green I'd have said you're out of gas", then when we looked a few minutes later, it had just changed to red. And when we manually turned over to show the state of the reserve, those showed red as well.

After getting another new set (and leaving the taps on the cylinders turned off until the heating engineer had checked for leaks), the boiler lit immediately, showing that the only problem was low gas pressure - no other intervention was needed.

Interestingly, the error code was very vague and the online manual did not say (effectively) "if you get this error code, you have probably run out of gas". But maybe the concept of running out of gas is unexpected, if the same boiler (with a change of burner) is also used for mains gas, when there will "always" be gas (unless the country's supply runs out, which it sounds we're getting rather close to according to news reports).

It's not the first time that a set of cylinders has lasted an unusually short time. My parents noticed it when they were there last summer for a few weeks - they had a delivery of cylinders which lasted only a few days and then the replacements for those lasted a long time. And that was in warm weather when the only heating is in an evening and for hot water for washing up (but not baths - that's on an immersion heater).

I do wonder whether there's an occasional problem with partially-full cylinders being supplied or hoses not being fully tightened, but proving it is very difficult: how do you weigh a couple of 47 kg cylinders, outside, while the engineer is still there and therefore demonstrably before any gas has been used? Take the bathroom scales out and sit each cylinder on them to check? Do all cylinders weigh the same amount when empty, given that there are several different designs - some are taller (and maybe narrower) than others.

Bloody bottled gas. Oil would be so much better - and a great deal cheaper. The only thing that *needs* gas is the fire in the dining room; the cooker is electric, so they don't need gas for cooking.

As a matter of interest, why is bottled gas always propane or butane, rather than methane (ie natural gas)? It's probably very obvious but I can't think why.

Energy.

Butane and Propane have a higher energy content than methane. You'd need much larger cylinders. From memory, I think LPG has about 3x the energy density of natural gas but I'm not sure if that is for butane or propane.

You can get gauges for cylinders and even things which stick to the side, although I've only seen the latter for smaller cylinders.

Propane and butane can be liquefied at room temperature by compression alone, so it occupies less much space; methane has to be cooled to a very low temperature as well.

You weren't there. Could someone have taken the opportunity to swap your nearly full cylinders for their nearly empty ones? The advantage of swapping, rather than simply stealing, the cylinders is that you might not realise and they can do it again in the future.

Who supplied the gas? about 20 years ago my MIL noticed some deliveries lasted a lot longer than others. It transpired that the driver was on the fiddle replacing part full cylinders at one house and delivering them in place of the full ones charged to MIL. It was another customer that found out. Having noticed the same he weighted the new cylinders and found one batch half empty!

Mike

Do the cylinders have the empty weight printed on them?

No they all weigh differently, even the same type. They have a tariff weight on them which is what they weigh when empty.

not strictly true ... you can now get plastic gas containers - weigh a lot less than steel