vaillent echtech 837 takes ages to get to 65c

[jkcov]

Iv posted before and managed to get my boiler fixed by an engineer after some good advice. I need some more help. If i set my boilers central heating to come on and set the boiler dial at 65c my boiler takes 38mins to reach 65c from cold. Is this right? It also keeps at 65c for over 40 mins after the inital 38 mins before it anti cycles. The reason i ask is because my boiler is using 1.49 m3 metric units of gas per hour every hour. Shouldnt the boiler get to 65c quickly. How much gas should i use when its set at 18kw. We have gas rated over two mins and the rating showd that it is using the correct amount of gas. However it continues to use this same rate of gas ie 0.072 every 2 mins and does not reduce which is making it use nearly 1.5 units an hour. Help would be appriciated. How long does ur vallient take to heat up? Does it rev up to temp quickly like the water does ?

 

[Agile]

If its taking so long to reach the set flow temperature then the obvious conclusion is that the heat requirements of the property are very close to 18 kW.

Increase the d0 setting to 20 kW and you should see a significant reduction in the time taken.

To reduce it further and if the weather gets much colder you will probably need to increase it further as we get into the winter.

Obviously any improvements in your insulation will have a significant effect on the power used.

Are you in Coventry? I am going there this weekend for a few days.

Tony Glazier

 

[Agile]

If its taking so long to reach the set flow temperature then the obvious conclusion is that the heat requirements of the property are very close to 18 kW.

Increase the d0 setting to 20 kW and you should see a significant reduction in the time taken.

To reduce it further and if the weather gets much colder you will probably need to increase it further as we get into the winter.

Obviously any improvements in your insulation will have a significant effect on the power used.

Are you in Coventry? By chance I am going there this weekend for a few days.

Tony Glazier

 

[gaswizzard]

Cubic metres /0.094 = kw

1.70 m3/0.094 = 18kw.

37kw x 0.094 = 3.4 m3.

0.072 over two minutes = 2.16 m3 = 21 kw net.

 

[bell824]

Cubic metres /0.094 = kw

1.70 m3/0.094 = 18kw.

37kw x 0.094 = 3.4 m3.

0.072 over two minutes = 2.16 m3 = 21 kw net.

sound's like burning 18 kw therefor what as has been asked of the boiler burning 18 kwas you set it to that, remember the boiler is burning this 18 kw slow and steady not hard and fast, if you set it higher it will burn 18kw faster and harder, you have asked it to do this and it is comprehending. most efficient way of using your heating (without all the super duper controls) is to match it to your house requirements and keep the thermal envelope of building warm,
Sounds ok to me in the short answer

 

[bell824]

usual late friday spelling

 

[gaswizzard]

I suspect D0 has been set to 14kw (47000 btu) / 1.5 m3 hr (input)

 

[jkcov]

If i change it to 22kw or even 28kw it takes the same amount of time to reach 65c but uses even more gas. The house is gettting hot quite fast. The rads have been properly sized and come to 17kw. To me it seems a lot of gas to use especially that my ave useage for this time last year was 5 units a day and i used to have the heating on constantly. I left my heating on over night set at 18c for 6 hrs (the house doesnt go below 17/16 c at the moment as its a warm house) and it used 9 units of gas.

Angie yes i live in coventry.

 

[ALEC1]

its sounds par for the course...but if you wanted to use less gas you could use a compensation controller such as the 392 or 430..

that way the temperature won't over shoot and the radiators won't get so hot if there isn't a big demand, i.e. temperature difference between set point (on the controller) and actual temperature...