Newbie help - water UFH Anti cycle with Valiant ecotech 831

[wattsie1987]

Do not leave it set this high, the max for that type of floor is around 50deg C

1. you could burn your bare feet (or cook a baby if it was left on the floor)

2. you can damage the floor / furniture

Thermo blending valve will prevent this tho....

That boiler can only modulate down to a minimum of 5kW as above it sounds as if your UFH is less than this so causing cycling.

 

[kash]

Thermo blending valve will prevent this tho....

That boiler can only modulate down to a minimum of 5kW as above it sounds as if your UFH is less than this so causing cycling.

How is it fixed then?

 

[wattsie1987]

How is it fixed then?

I don't think it can be. Decreasing the heating partial load will increase heat up time and take longer to get to the cycling stage but will then have an adverse effect on the radiator circuit. Its like trying to get a car to do 5mph in top gear.

 

[chris watkins]

11.1.4 Setting the return flow temperature control
If the boiler is connected to an underfloor heating system, the temperature control can be changed from flow temperature regulation (factory setting) to return flow temperature control under diagnosis code "D.017".

Have you checked the temp control setting has been changed from flow to return? as per MIs

 

[chris watkins]

I went round to my parents today and set the anti cycle time to 5 mins, and set output to max + heating flow temp to 76 degrees.

I also set the thermostat on the UFH mixer to max (70degrees).

It takes about 5/6 minutes for the boiler to go into anti cycle mode.

Is there anyone that's willing to come out and help, or can anyone be recmommneded? Based in southall- Ub1

Thermo blending valve will prevent this tho....

That boiler can only modulate down to a minimum of 5kW as above it sounds as if your UFH is less than this so causing cycling.

He has set it to 70 max so it be blending much.

Kash that sets the water temp circulating in the UFH pipes & will give a very high floor surface temperature, the room stat is only picking up the room air temp.

 

[kash]

He has set it to 70 max so it be blending much.

Kash that sets the water temp circulating in the UFH pipes & will give a very high floor surface temperature, the room stat is only picking up the room air temp.

Mixer stat is now back at 50.
I should have said that the other digital room stat is set to floor temp only. It has the option to be air temp, and and floor temp or floor temp only.

 

[kash]

I spoke to valiant this morning who said it will more then lilkey be a balance/circulation issue.

Now I just need someone to come and look at it for me....

 

[kash]

I had a company come out who told me that i needed to power flush my whole system (only installed 2 months ago) and that I should probably fit a bypass valve as this was probably causing the problem.

I will get a bypass valve fitted by not by them - they wanted £140 an hour and he said I'd be looking at half a days work just for the valve, which I'm not so sure about. They also charged me £96 to come out and have a look. he spent 45 minutes just talking to me and shining a torch at the system, then said well i cant do it today anyway so need to come back!? not sure why he bothered coming out in the first place.

Ive had a quote for £150 to fit the valve and check the system over and get it up and running properly so will give this independent installer a try.

It seems that not having the bypass valve is causing the boiler to enter anticyle mode. watch this space, will let you know how i get on.

Here are some pictures of my setup that for some reason, i couldn't add before!

 

[rpm]

Most likely because you`ve now posted 12 times Kash and are considered safe not to post any "unsavoury" photos if you get my drift. lol

 

[kash]

I have a plumber in at the moment! Finally! somoneone who turned up when they said they would!

fitting a drain valve to make the system easier to drain in future and installing a bypass valve as we speak.

Watch this space - fingers cross that this will be the solution to my problems!