GEMINOX BOiler with RVP75.230 Controller

[AK22]

I have a technical query, which I hope someone may be able to help me with. -

Ever since I installed this boiler some 12 years ago, I have not been entirely convinced that the Landis and Gyr (now Siemens) RVP75.230 controller is doing its job properly.

Unless I manually override the three way mixer valve, and set it the mid position, the flow to the radiators is nearly always too low, usually well below 60 degrees.

What should the RVP controller in the Geminox FCX 20 E be trying to achieve, by varying the proportions of water taken from the boiler and the condenser?

I understand from the Geminox Manual, page 6, Section 5 "The Condenser", that "......with a return water temperature of 53 degrees or less, the condenser will abstract latent heat as it cools the flue gases to below the dew point.........."

As the boiler has never been fitted with a return water temperature sensor (TEMP 5), can it achieve this, and if so how?

Many thanks for any help which may be out there.

Regards

Alan K.

 

[Agile]

You have not said which model of boiler this is.

Although you have said the YOU installed it, I am guessing that you are not a registered installer and you really mean that someone installed it for you. Does the installer understand yours?

There are few in the UK and virtually no support so I dont expect you will get any help here. I only know of two in the London area!

Are you sure it does not have sensors on either side of the heat exchanger?

Tony

 

[AK22]

Tony,

Many thanks for following up my query.

The boiler is an oil (28 sec) burning Geminox FCX 20 E. (Re-badged as YorkStar)

I purchased boiler, tank, and all the associated ancilliaries such as expansion vessel, and pressure reducing valve from YorkStar and installed them myself.

Apart from this one concern I have about the controller operation, the system has been giving stirling service for nearly 12 years, with nothing required other than an annual service, (which I also do myself). I also once had to fit a new solenoid coil in the burner valve.

The only sensors fitted are

TEMP 1 (B2) Boiler temperature
TEMP 2 (B3) DHW Tank temperature
TEMP 3 (B1) Central heating water flow (feed) temperature
TEMP 4 (B9) Outside Air Temperature
TEMP 7 (B5) Room Temperature

There is no sensor fitted to the controller TEMP 5 input (boiler return temperature)

Thanks once again

Regards Alan K.[/b]

 

[Agile]

I thought York Star were originally actual manufacturers and closed down some while ago. Perhaps they never made and only rebadged? The oil specialists may be able to give further information. Could you add "York Star Oil" to the title by editing so that they are alerted.

As far as I am aware Geminox is still a small but functioning French manufacturer. Quite a lot of boilers were sold under the York Star brand name in the UK.

I dont think that I will be able to help you but its always possible that one of the oil specialists might have such detailed knowledge or alternatively you might be able to make enquires in France.

There is a small UK company which provides limited support in the UK and has some spare parts but their technical competence seems very limited which is why one customer has engaged me to look after his Geminox boiler.

Tony

 

[AK22]

Tony,

Thanks once again for your feedback.

I have had a great deal of invaluable help from the Tech Support guys at Geminox in the UK (now Evinox - http://www.evinox.co.uk), however, they are not familiar with the RVP75.230 controller which was fitted by Yorkstar.

I have trawled the net trying to find a manual for the RVP75, but without success.

Just in case the boiler was accidentally supplied with the sensor missing, I think I will get LG-Ni temperature sensor and attach it to the CH return pipe and wire it up to TEMP 5 Input and see whether this changes the behaviour of the controller.

Regards

Alan K.

 

[Agile]

The controller may well have to be reconfigured to work in a different mode if a return sensor is fitted.

If you dont have full instructions then you might not be able to achieve that.

In an ideal world you might think they would design it as plug and play but then it might try to adapt itself to something else in the event of a failure.

Imagine an Airbus A320 where one engine sensor failed and so it decided that it only had one engine and therefore must be a helicopter !

One crashed at the Paris air show when flying very low when the plane decided that it must be landing so continued its descent and crashed into the trees.

Tony

 

[Boilerman2]

I do service one of these boilers in Chelmsford (essex), the RVP control is a small commercial Weather Compensating control, with a hot water control function.

The Hot water takes priority, once the HW is up to the selected temperature, the contoller looks at the Rooom Temperature and the outside temperature, and calculates the required flow temperature, and as you have an oil fired boiler, this is regulated via a 3 port motorised mixing valve, which mixes flow & return water, to provide regulated water to the radiators, in simple terms, the colder it is outside, the hotter the flow i.e. -1*c will give approx 80*c to the Radiators, 15*c will give approx 30*c to the Radiators. The Room sensor will cause a downward shift of radiator temperature as the romm temperature gets toward the setpoint of the Room setter. -- sounds complicated?? thats because it is, my advice would be to contact a Commercial Heating Company ,they should know about the RVP Control, as they are quite common in small commercial properties,, long winded! but I hope I have helped!!

 

[AK22]

Hi. Many thanks for your input.

The information you have provide is very useful, and I think confirms that since it was installed the RVP75.230 in my Geminox boiler may never worked correctly with regard to radiators!

Except by manually overriding the 3 port mixer valve, I have never been able to get CH water flows at the temperature you described.

After (too) many years in industrial instrumentation I have a basic knowledge of control systems and electronics, and if you would be able to answer one or two more questions, I am fairly certain I can get to the bottom of this one!

If, during assembly, the wiring to the 3 way motorised mixer valve had been transposed (i.e. valve being driven in the wrong direction) I think this could possibly produce the symptoms I have described......

The majority of the time, the display on the RVP shows a small downward pointing arrow head along with a pump icon with a number 1 in it, which I believe indicates that the internal relay Y2 is energised to 'close' the mixer valve. I this context, does 'close' mean closed to the condenser, or closed to the main heat exchanger water jacket?

I hope that all makes sense, and look forward to receiving your comments.

Thanks once again.

Regards

Alan K.

 

[Boilerman2]

Y2 is 0% heat output, or Full Recirculation of heaing water, i.e the shoe inside the 3 port valve is closing the hot water from the boiler, so the circulation is being diverted away from the boiler, Y1 will cause the valve shoe to block off the recirculation pipe so that water flows from the boiler into the heating circuit ( usually the valve will very slowly modulate between open & closed theby mixing heated and recirculated water to create the required flow temperature)

 

[AK22]

Thanks again for your helpful comments.

I spent yesterday analysing the behaviour RVP and this is what I found

Controller set to Auto Mode and heating ON
- Slider switch set to Normal Operation


Temperatures set in RVP

Day time Room temperature set-point (Sun symbol 20 deg. C
Night time Room temperature set-point (Moon symbol) 14 deg. C
Domestic Hot Water tank temperature (Tap symbol) 50 deg. C
Frost protection temperature (snowflake symbol) 10 deg. C.
Summer / Winter change-over t emp (Parasol symbol) 17 deg. C


Temperatures Measured by RVP

TEMP 1 (B2) Boiler temperature 78 deg. C
TEMP 2 (B3) DHW Tank temperature 60 deg. C
TEMP 3 (B1) CH water flow temperature 37 deg. C
TEMP 4 (B9) Outside Air temperature 4 deg. C
TEMP 5 Boiler return temperature (no sensor fitted)
TEMP 6 Flue gas temperature (no sensor fitted)
TEMP 7 (B5) Room temperature 15 deg. C
TEMP 8 Second Room temperature (no sensor fitted)
TEMP 9 Maximum Flue gas temperature (no sensor fitted)


Outputs from RVP

Display

Boiler Burner symbol (relay K4)
Sun Symbol
Pump 1 Symbol (relay Q1 indicator
Down Arrowhead (relay Y2 indicator)

Electrical

Relay Y4 energised - burner on
Relay Q1 energised and CH circulating pump running
Relay Y2 energised for about 1 second every 10 seconds (continually)



Can you think of any reason why, under the above conditions, the Relay Y2 is not activated to increase the CH temperature flow?

Regards

Alan K.[/u][/b]

 

[Norcon]

Here's a pdf link to your controller...........
http://tiny.cc/A0WVc
I think its polish.

 

[AK22]

Many thanks for the link to the manual.

I can tell from the diagrams that this is what I need!

All I need now is a Polish / English dictionary and a lot of patience

Anybody know the whereabouts of an English version?

Thanks again..............

 

[Norcon]

You could try google translator but I've had no success with it on this link.
Perhaps someone knows a way.

OK you can highlight text here and copy and paste into google translate...Its Polish.
http://www.sbt.siemens.pl/_files_/hvp/instrukcje/P2440pl.pdf

 

[AK22]

Hi.

With a little (lot) of help from you guys out there, a Polish welder here at work, perseverance with "Google Translator" and some trial and error, I found that the ADAPT value set up in the RVP75.230 has always been set way too low (12.5).

Having increased this to 25 (i.e. the top of the radiator range), when the demand for domestic hot water has been met, and the room temperature is below the desired value (setpoint) the controller now behaves as follows:-

Whilst the water jacket temperature is below about 78 degrees, the burner is turned on, along with Y2 (down arrow displayed) and CH heating water is circulated through the condenser.

When the water jacket temperature exceeds about 78 degrees, the burner is turned off, and Y1 is turned on (up arrow displayed) to circulate the CH water though the main boiler water jacket.

When the boiler water jacket temperature drops to somewhere about 50 degrees the above cycle begins again.

I have not yet been able to run the heating system for long enough to confirm that everything is as it should be, but it is certainly a lot better than it has ever been in the past!

Can anyone confirm that the observed operation is correct?

Many thanks to everyone who has chipped in with help

I am planning to get the whole 66 page manual translated, and if anyone would like a copy please drop me an e-mail to [email protected].

Regards

Alan K.

 

[Boilerman2]

Try www.spartancontrols.co.uk

They are very helpfull, to get heat around the Rads you need Y1 (arrow up) to energise Y2 will close the valve, (just a thought there may be a shift programmed to maintain 50*c on the Boiler return (as the boiler is oil fired return should be at least 50*c to maintain temperature above "dew" point