have I got it wrong?

[diydad888]

Hi folks,
Need some advice about getting the best out my heating system.
Some background...apologies in advance,
I have a typical early 1960 wimpey 3 bed semi detatched house, first of the modern house designs so all quite small and zero cupboards ! 3 beds up stairs, living room/diner and kitchen and bathroom downstairs.
I added a small front porch (2.5 mx2.5 m) and extended the living/dining room to the rear with a 5 m x 3m extension.
Recently I had a new worcester greenstar 15 ri regular boiler fitted to replace an ancient Baxi.
I have just replaced all my original radiators with now Kudox models, the old rads were a mixture of single and double panels, I replaced same size as close as I could but used single panels with the convector waffle bit, my thinking was that the new rads will be more efficient (and cleaner inside!) so I could save money and space by using singles only.
My extended living/dining room has 3 rads 2 of 1200x500 and one 1400x500 this lot keeps downstairs very warm, bed rooms are fine if I open the TRV's I have difficulty heating the bottom of stairs and front porch area as I did not put a rad in the new porch and thought instead to just move the original rad location closer to the porch area I used a single panel 500x600 high, the porch is open to the house, no internal door as we like the space. Brand new high recovery insulated cylinder.
When the boiler is on (max) it is heating non stop, it does not cut out until I turn down or off, is that normal and best practice? should it cycle on and off? or stay on until temp is achieved.
Can I put a larger double rad in my hall way, can this boiler cope with more?
Do I need larger radiators so the return to the boiler is cool enough?
Do I need a larger boiler?
I am not sure the boiler and rads are matched.

Thanks

 

[Slugbabydotcom]

my thinking was that the new rads will be more efficient (and cleaner inside!) so I could save money and space by using singles only.

Erroneous thinking! It's all to do with heat output measured in Kw/h or BTU

It seems you have reduced your heat output so those rads you replaced will now struggle to heat the room/s.

the boiler keeps on running because the room with the stat in it is not being heated sufficiently. The boiler will run and run until either the boiler stat cuts it out or the room stat eventually is satisfied.

A 15Kw boiler should be sufficient for the house as you describe, especially if you have all your insulation in place.

 

[diydad888]

Thanks,

I forgot to mention the thermostat is in the small hallway off the front porch so probably the coldest area, I was thinking it was best to leave it there but of course that area will never get to say 20 deg in winter with a 500x600 rad to warm the short hall and large porch.
Do you think I would be better to put the stat in the living/dining room and then put a double/larger rad in the hall with a TRV.
The porch hall area does not need to be same temp as the main part of the house.
The TRV's in the living room do a good job and control the heat fine but the stat and small rad in the hall area can never reach temp.

Thanks

 

[Slugbabydotcom]

Recommended temp for a hallway is 16ºC. Does it have a chance of reaching that?
Experiment with the setting, you may find a 'happy place' for it.
If that fails then consider moving it or maybe it would be easier to replace it with a wireless stat or programmable roomstat.

 

[diydad888]

Thanks for the tip, yes the wee hall can reach 16 deg ok but if I set the stat (in the hall) to 16 then the other rads wont heat up. I guess I should get a new stat as you suggest move it to the living room? and leave the trv maxed in the hall.
Where is the best/recommended place to put a general stat?

Thanks again

 

[Slugbabydotcom]

Away from heat sources such as radiators and electrical equipment. Out of direct sunlight and draughts and generally somewhere where it can best sense the average room temperature.
They all come with instructions so have a read through.

Set the hall stat to 1 or 2. Why heat up any room hotter than it needs to be?
The idea of TRV's is that they turn off when the room is at a comfortable temperature and thats when you save money.

However the only one I would set to max is the one with the room stat in. the room stat will control the heat in there.

A long long time ago they did a study into comfortable room temperatures. It not hard and fast rules because everyone is different but the suggested temp was [from memory] as follows
Hall 16ºC usually setting 1
Bedroom and Dining room 18ºC setting 2
Living room 21ºC setting 3
Bathroom 23ºC setting 4 but you could save money here by turning it down to 2 when the bath or shower are not in use.
Remember the hotter a room is the quicker it will lose its heat = more fuel used. Your goal is to make no room any hotter than it needs to be to save money.