How does boiler temp translate to room temp?

artesin

So my housemate likes to turn the boiler on full blast ALL THE TIME, this boiler doesnt have any temp indicators but if its anything like the one from last year then that means its getting heated to 85c, as opposed to the minimum temp of 45c. How do these both translate to room heat?

CashStrapped

A boiler usually has a dial or two dials. One for radiators and one for taps.

Boiler Controls
Both these dials control the water temperature. The higher they are set the hotter the radiators will get and the hotter the water out of the hot taps will be.

Room Temperature conrols
The second control that people often get confused about is a room thermostat. This is the dial, usually on a wall somewhere, which has numbers relating to room temperature on it.

People often mistake the room thermostat for a boiler temperature control. It is not.

All the room thermostat does is turn the boiler off when the room has reached the desired temperature.

Using Boiler and Room Thermostat

So, if you have a room thermostat, you can have the boiler on full for the radiator water temperature. This means the radiators will get super hot and the room will heat up very quickly. Once the room is at the temperature set on the room thermostat, the boiler turns off.

If you have the radiator water temperature set to low, the room will just take a lot longer to warm up before the thermostat turns the boiler off.

In both these cases, once the room temperature drops too low, the thermostat will detect this and turn the boiler on again.

No Room Thermostat?

If you do not have a room thermostat, then you have to carefully control room temperature using the boiler controls. You have to manually do the job of the room thermostat. Manually turning off the boiler when it is warm enough and turning it back on when it is too cold.

My room thermostat is broken. So I carefully set the boiler to warm the radiators to a level that keeps the same consistent temperature all day.

The boiler will only fire up to maintain that set temperature.

If however your housemate sets the boiler on full, all the time, the room must be stiflingly hot! Is this the case?

I have a few digital room thermometers around the house to confirm what my room temperatures are at to help keep a consistant temperatutre.

artesin

We dont have any room thermostats, and im pretty sure the radiators do not have TCVs. They just have two nobs to open and close the valves on each side. Its annoying since he turns the radiator on high, I have to turn my radiators off at night since he seems to forget to turn the boiler off, resulting in the room getting stifling.

Were just in a constant battle of turning the boiler control up and down since I think it is completely unreasonable to turn the boiler all the way up without even throwing a sweater on first -.-

So since I dont have any thermometres to test the ambient temp Im trying to figure out if there are any general guidelines as to how hot a room will get at a certain boiler temp with the radiator valves fully opened. Say if the boiler is set on 65C and the room is a typical size double room.

Cardew

You obviously have a very old CH system.


The boiler water temperature control determines how hot the radiators will become. If your radiators don't have TRVs and no room thermostats in the property, then the water in the system will rise to the temperature set on the boiler.


Setting the temperature to 65C as you suggest will not produce a constant internal temp of, say, 20C. It will depend on the outside temperature and how many radiators you have switched on in the house.


For a couple of pounds you can buy a thermostat to monitor the inside temperature, or don't some smart phones have an app to measure temp.

JJ_Egan

With my similar old system i set the boiler so as the radiators do not get very very hot .
Using the valves i then set each radiator to a rough heat . That is unused bedroom heat low , hall heat high .

Alter_ego

The utility bill should help control his need for high temperatures.

Nathan94

artesin wrote: »

So my housemate likes to turn the boiler on full blast ALL THE TIME, this boiler doesnt have any temp indicators but if its anything like the one from last year then that means its getting heated to 85c, as opposed to the minimum temp of 45c. How do these both translate to room heat?

The boiler thermostat controls the temperature to which the boiler will heat water.

However most CH systems have another thermostat on the hot water tank which should ideally be in control for hot water. That mewans the boiler thermostat should be set higher than the cylinder one (otherwise the boiler will be in control)

The room temperature should be controlled by the room thermostat.

Cardew

Nathan94 wrote: »

The room temperature should be controlled by the room thermostat.

From the OP - post#3

We dont have any room thermostats, and im pretty sure the radiators do not have TCVs. They just have two nobs to open and close the valves on each side.

Cardew

artesin wrote: »

and im pretty sure the radiators do not have TCVs. They just have two nobs to open and close the valves on each side. Its annoying since he turns the radiator on high,fully opened.

I assume by TCV you mean TRV(Thermostatic Radiator Valve)?


Without a TRV the 'two nobs(sic)' will not affect the temperature of the water in the radiator. It will rise to whatever temperature is set on the boiler regardless of knobs being fully opened or slightly open. Turning the knob down will simply restrict the flow through the radiator to enable all radiators in the house to be balanced, but eventually all the radiators will be at the set boiler temperature.


With a TRV the water will still be at boiler temperature, but the TRV will open and close to achieve the desired room temperature.

CashStrapped

You have two options

1) Confront your housemate. Who pays and monitors the gas use? You could use the high gas use as a reason to talk about it. Somtimes the cost of doing somthing shocks people into changing habits. Being responsible for bills often does this.

2) Ask the landlord to install a wireless room thermostat. That way the house will only heat to to a temperature you set for the room you are in. Then keep it in your bedroom! Ok, the last bit is a bit extreme, but a room thermostat (wired or wireless) should help the situation.

You could try both those options really.

D_M_E

There's only 2 choices:

1. Find a new housemate, or

2. Find somewhere else to live, and do it very soon.

Have you had any energy bills yet, or are they included in your rent (if renting)?

If no bills as yet, read your meters and contact your suppliers and get an up to date bill and, when you have recovered from the shock induced by looking at the numbers, confront your housemate and point out that buying and wearing a vest would cost less than the cost of the energy used in a day to keep the heating at tropical.

Better still, if it's not you who is responsible for the bills then someone else - possibly your housemate - is.