How to improve heating system

Rosabear

Hi all, we moved into a new house in December and I'm shocked at the amount of gas the heating uses. It's about 130kwh for 7 hours set on the middle boiler heat setting. It's a 5 bedroom terrace (so large) but half of the 12 rads are turned to frost as rooms not in use. 

We have a worcester greenstar cdi34 which is between 7 to 10 years old and has been serviced. There is no room thermostat and the boiler timer is broken. The rads have TRVs but some have stuck. 

Looking at the usage on EDF's website there doesn't seem to be much variance between each hour of use so I'm wondering if there's something wrong or inefficient with the boiler as I thought modern ones modulated? 

We have the option to have a new boiler fitted but should we start with looking at new control systems like hive or digital TRVs? Is 10 years time to replace anyway? 

It's the first house we've owned so first time it's all on us to make decisions! Thanks for your help.

FreeBear

Fitting a thermostat is a "no brainer" - Get a programmable thermostat that allows you to set different temperatures during the course of the day. It doesn't have to be Nest or Hive - The Drayton Wiser would work just as well (also a number of even cheaper units available).

Certainly worth replacing the TRVs if they are not working. Personally, I wouldn't bother with digital ones (expensive, need regular battery changes, locks you in to one system). Replacement TRVs are £7-10 each for the head & valve compared to £40-100 for digital (and that is often just the head).

I would suggest fitting a programmable thermostat, replace the TRVs with basic ones. Have the radiators balanced, and see what your gas consumption drops down to. Save a bit of money each month, service the boiler, and replace when it fails.

Rosabear

Thanks FreeBear. That's definitely food for thought on the TRVs!

MWT

Rosabear said:

The rads have TRVs but some have stuck.

If it is just the valve stuck there are numerous videos online with simple instructions on how to release it so you may not actually need to replace these...

BUFF

FreeBear said:

Fitting a thermostat is a "no brainer" - Get a programmable thermostat that allows you to set different temperatures during the course of the day. 

Absolutely this. Last time I changed my heating system I reckon that 1/2 of the savings came from adding a room stat.

ManMadeWays

I have fitted Drayton Wiser kit to a 12 TRV rads (also have 3 non TRV bathroom rads) set up schedules/temperatures per room.

Eagerly awaiting month end to check usage, hoping to save circa 30% of the 28,000 Kw/h gas we use over a large 3 story Semi.

If you bought the Wiser Boiler Hub plus Thermostat (Starter Kit at circa £145) , although this a bit more expensive than the non smart version Drayton 123042 Digistat +3RF & Receiver, White at £87 , it gives you the flexibility to add Smart TRVs later, and also smart plugs for lights etc.

All my kit cost circa £600 but will payback in under a year at 8.5p Kw/h.

I'm on a fixed rate for this year so I expect my bills to go DOWN !

Edit : I assume you have got the usual insulation in loft, double glazing, radiator insulation panels on walls behind radiator, sealed fireplaces etc ?

Gerry1

Rosabear said:

It's about 130kwh for 7 hours set on the middle boiler heat setting.

That period is a bit too short to draw meaningful conclusions.  Better to take the average of the results for a few days.  How did you arrive at the kWh figure?

Rosabear

ManMadeWays said:

I have fitted Drayton Wiser kit to a 12 TRV rads (also have 3 non TRV bathroom rads) set up schedules/temperatures per room.

Eagerly awaiting month end to check usage, hoping to save circa 30% of the 28,000 Kw/h gas we use over a large 3 story Semi.

If you bought the Wiser Boiler Hub plus Thermostat (Starter Kit at circa £145) , although this a bit more expensive than the non smart version Drayton 123042 Digistat +3RF & Receiver, White at £87 , it gives you the flexibility to add Smart TRVs later, and also smart plugs for lights etc.

All my kit cost circa £600 but will payback in under a year at 8.5p Kw/h.

I'm on a fixed rate for this year so I expect my bills to go DOWN !

Edit : I assume you have got the usual insulation in loft, double glazing, radiator insulation panels on walls behind radiator, sealed fireplaces etc ?

Ah that looks good, thank you so much. We could do with boosting the insulation definitely and it's on the growing list of things. Definitely a priority though. The two parts that need more are quite hard to access so still trying to work out a method!

Rosabear

Gerry1 said:

Rosabear said:

It's about 130kwh for 7 hours set on the middle boiler heat setting.

That period is a bit too short to draw meaningful conclusions.  Better to take the average of the results for a few days.  How did you arrive at the kWh figure?

Just by looking at EDF's website as we have smart meters but no working IHD. They're hopefully coming out to fix it but it's been several weeks now. 

coffeehound

Hello.  Do you have a hot water tank?  What is the thermostat set to, if so?

For the non-working TRVs, have you tried unscrewing the tops?

Ally_E.

That's a normal usage for such a big house if it's older build, like a period property? We use 132kW a day in our 1930s solid brick wall house, 3 bedrooms. Thermostat at 18C and boiler on 40C return flow temperature, so condensing nicely and working efficiently.