Help understanding thermostats - room/boiler

ripplyuk

I've been looking this up on google but I still don't understand. I have a conventional boiler. It uses oil, not gas as its a rural area. The house has a room stat and trv's on all radiators except one. I've been setting the room stat to 18 degrees and turned down the trv in the bedroom as it was too warm.

The boiler itself has a dial on it to adjust the temperature. It doesn't have 'degrees', but it can be adjusted between min and max.

I'm wondering what is the most cost efficient way to set this? I'm struggling to understand what the boiler thermostat does. Does the room stat not set the temperature? Should I have the boiler set to min or max?

Cardew

The boiler thermostat simply sets the temperature of the water in the central heating 'circuit'. The higher the setting the quicker rooms will heat.


However in simplistic terms if the boiler is a condensing boiler, generally speaking the lower the water temperature, the more efficient the boiler.

ripplyuk

Mine isn't a condensing boiler. Its 10 years old now but the man who serviced it said its still very efficient, around 93% I think. It's a rented house so I can't replace it.

It sounds good that the house will heat up quicker. Do most people just keep it turned up to max? Or, is that more expensive? Should it be different in summer than winter?

Cardew

ripplyuk wrote: »

Mine isn't a condensing boiler. Its 10 years old now but the man who serviced it said its still very efficient, around 93% I think. It's a rented house so I can't replace it.

It sounds good that the house will heat up quicker. Do most people just keep it turned up to max? Or, is that more expensive? Should it be different in summer than winter?

Do you mean it is 'not a condensing boiler' or 'not a Combi boiler'?


New/replacement Condensing boilers have been mandatory since 2005. Also a non-condensing boiler will not achieve 93% efficiency; albeit the servicing man cannot measure efficiency.

ripplyuk

I'm not sure. I asked the man what sort of boiler it is and he said its just a conventional one, not the more modern type. It was installed in May 2005 so maybe it is condensing. It says on it that its a '50/70 Bluebird', if that means anything. The man left a print out from the servicing and it says the net efficiency is 92.3%.

HappyMJ

ripplyuk wrote: »

I'm not sure. I asked the man what sort of boiler it is and he said its just a conventional one, not the more modern type. It was installed in May 2005 so maybe it is condensing. It says on it that its a '50/70 Bluebird', if that means anything. The man left a print out from the servicing and it says the net efficiency is 92.3%.

It's a Warmflow boiler

Band C - Non condensing 85.6% SAP efficiency.

http://www.homeheatingguide.co.uk/efficiency-tables.php?model=008062

Still a good rating though. Replace only when uneconomical to repair.

It's older than 2005 as they were manufactured from 1996-2000.

matelodave

You can usually tell if it's a condensing boiler (whether conventional or a combi) by the plume of steam that comes out of the flue. Anyway that's irrelevant to the discussion.

Ideally you should have the boiler stat around 1/2 in the summer and about 3/4 in the winter. The radiators should feel hot about 10-15 minutes after the heating is switched on (not lukewarm or scalding). That will determine how quickly the room warms up, increase the boiler temperature a bit if you want it to heat up a bit faster. Too low a boiler temperature and the room wont get hot enough for the room stat to control it.

The room temperature is controlled by the room stat. Turning it up won't make the room warm up any faster, it will just get hotter until the stat switches the pump & boiler off. It then switches the boiler 7 pump on and off to maintain the room temperature.

Makes sure that the stat is in a room which has a radiator in it and that the radiator does not have a thermoststic valve - if it does make sure it's fully open.

The best place for the stat is in the living room (unless you've got a fire or other form of heat in there).

Most places have it in the hall which isn't always the best place as frequently it's draughty especially when someone opens the front door. The radiator isn't usually big enough to heat the whole hall and most of the heat goes straight up stairs. If it is in the hall then you'll have to adjust it to reflect the lower temperature in the hall and control the room temperatures with the TRV's