CTS / CHILTERN TECHNICAL SYSTEMS : TEL / FAX 0117 966 9893
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We can supply a
suitable armoured gas hose and pre set regulator, all ready to go and factory adjusted so
that you can't loose the settings!
identification: Mk 1 - pre October 2000
identification : Mk 2 - post October 2000
identification : Propamiser special build There are no significant alteration to user serviceable components between the types.
If the unit works well until it shuts down at the specified temperature at which time the flame in the pilot extinguishes or begins to lift off the pilot burner so that the thermocouple cools down and the flame fail system activates, this indicates a gas pressure problem and is likely to be caused by someone fiddling with the regulator or dirt in the seals. Reduce gas pressure and set up the regulator and thermocouple again as shown on this page. HERE If this doesn't cure the problem, change the regulator and fit a high quality one with an input filter. If the problem persists or the gas pressure gauge will not zero when the gas supply is turned off at the cylinder, please phone us for advice. CTS phone & fax number: 0117 966 6677
At the correct pressure, when heating from cold, the gauge will be at '5 o'clock'. Here it is at zero. This gauge will also show you the state of the control system - the pressure will drop as the control system reduces the output of the burner when the cut off temperature is reached. As the temperature reduces, the gauge will show an increase and the main burner will light up to reheat the material. If left for a long time the system may reach a steady state and 'modulate' where the burner will remain alight at a low pressure and supply just enough heat to keep the material at the correct temperature. However on site this is unlikely to happen due to the varying conditions round the boiler.
OOOPS! Massive overpressure! Perhaps someone fitted a 4 bar regulator as the gauge won't go back to zero !! This one needs factory service! You can't fix this yourself - don't be tempted to open the box or you could do expensive damage. In fact the Propamiser was still working well but if this happens it is best to have it checked out.
CTS / CHILTERN TECHNICAL SYSTEMS TEL / FAX 0117 966 6677 |
USER MAINTENANCE & SET UP FOR CTS PROPAMISER CONTROL SYSTEM Most units work for years with no trouble at all, but this page is designed for those who want to know a bit more about the system and how it works. IMPORTANT: Do not work on this equipment unless you are competent to do so. This is an outline of the operations required and does not include basic safety requirements - if in any doubt return the unit for service or contact your o.e.m. THERE ARE NO USER SERVICEABLE PARTS IN THE BOX AND BREAKING THE SECURITY SEALS WILL INVALIDATE THE CALIBRATION AND WARRANTY The most common problem is a wet, dirty or burned out thermocouple. This is part of the automatic safety shutdown system and must be operational for the rest of the unit to function. It is failsafe and does not involve any gas connections, so you can probably do this yourself. It works by passing a tiny electric current to the control box to tell the system the pilot flame is alight. It does this because the tip of the sensor is positioned in the pilot flame that burns continuously, and thus remains very hot - a dull red colour is the correct temperature! If the flame is extinguished, then the thermocouple cools and the box shuts down in about 20 seconds to prevent a gas escape.
QUICK FIX! The amount of electric current is very small, so water or dirt can seriously affect the connection. It is well protected but driving rain or excessive dirt in very wet conditions may cause a problem.This picture shows a thermocouple fitted to the back of the box. If something goes wrong with the connections of the thermocouple, the unit will light up but the pilot and main burners go out as soon as you let go of the 'flame fail' button. Here you can see the connector socket on the back of the box. The thermocouple is a service part, cheap and easy to change. You do not have to open the box or disconnect any gas fittings.
Identify the thermocouple by studying the photograph on the left - it is the copper wiggly thing with the brass ends. One end is mounted in the pilot burner flame, ( the grey bit with the big nut ) and the other screws into the box. Unscrew the small thermocouple nut ( later models have a special extended nut and a shorter control unit with a BLUE button but it works the same way) from the connection in the back of the control box, - you won't have the small spanner required, but a pair of pliers will do. Very gently clean the end of the thermocouple, dry the socket fitting ( toilet paper is the best but don't leave any bits in the fitting ) and re assemble carefully, without putting too much torque on the thread! A smear of Vaseline may help, but not too much!
Make sure that the tip of the thermocouple is in the pilot flame and that the flame is actually heating the end of the unit! The pilot jet may need cleaning and in some cases, for instance if the gas pressure is too high or if the air holes are blocked, the flame may lift off the burner and while it will seem to be alight, it won't be heating the important part of the thermocouple and the control unit will think the flame has gone out and refuse to operate after the flame fail over-ride button is released! This shows a FARVIS pilot unit and you can see the thermocouple , securing nut and pilot burner air holes.
If neither of these work, you either need a new thermocouple, available from CTS or your o.e.m. or the box needs to be returned for service. Remove the sensor end of the thermocouple from the bracket by loosening the large nut and withdrawing the probe. Be careful to retain the 'olive' that secures it in position. If the fitting body comes loose it can be resecured before refitting the new probe. In an emergency, most cylinder gas dealers will have something that will fit but may not have the bits to retain the thermocouple in the pilot light assembly. However this will get the unit back into use until the correct parts arrive!
IF YOU USE YOUR OWN GAS REGULATOR: THIS IS N O T NECESSARY IF YOU BUY A COMPLETE UNIT FROM FARVIS. RESETTING THE REGULATOR GAS PRESSURE There is a lot of leeway built in !! NOTE: IF YOU BUY AN ARMOURED HOSE AND REGULATOR SET FROM CTS THIS WILL HAVE BEEN PRE-ADJUSTED IN THE FACTORY AND WILL NOT NEED ADJUSTING AS THE MAXIMUM PRESSURE HAS BEEN SET THIS ADVICE REFERS TO AFTER MARKET REGULATORS AND UNITS SUPPLIED BY OEMs The unit is designed to run at 2 bar ( 30 psi ) on PROPANE ( orange cylinders ). If the gas pressure goes well over this it may damage the inside of the box and you will have to send it back for repair. On later models with the BLUE flame fail over ride button there is a great deal more tolerance. It is essential that on first use the regulator is adjusted so that when the pilot light is running, but the main burner is OFF, the gas pressure indicator gauge does not exceed 2 bar. There is considerable leeway but it is best to assume that this is the maximum to be sure. Depending on the type of regulator you use, the pressure will be slightly lower when the main burner is in operation, but the pressure MUST NOT exceed 30 psi when the pilot only is on. FOR THIS REASON, ONLY A GOOD QUALITY 0 - 2 BAR ADJUSTABLE REGULATOR with an input mesh filter SUCH AS THE CALOR P1991 OR THE BULLFINCH 'TINYREG' SHOULD BE USED. The pilot burner uses a small quantity of gas and a cheap reg may not be able to control the supply at a low output and may increase the gas pressure so that the pilot blows out. Low quality regulators are not recommended - you get what you pay for! The next bit is only for those who are really keen! The easy way is to buy a pre-set hose and regulator from CTS. However if you have your own good quality regulator and need to set it up, it is easy..... honest !!! With everything set up and leak checked, start at nil gas pressure on the cylinder regulator with cylinder gas cylinder tap open, Propamiser main burner tap ( yellow ) OFF. Press the flame fail over ride button, and increase the pressure with the regulator control (NOT the gas cylinder tap) until the pilot flame lights. When the thermocouple is heated and the pilot remains alight with the button released, leave the main burner tap turned off ( yellow handle) and increase gas pressure on the regulator until the gauge reads 30 psi - ( remember that it MAY not indicate any pressure at all until the button is released!). Lock the regulator with the thumb wheel and check the adjustment hasn't altered on pilot setting. No further adjustment should be needed. Control burner output using control tap on Propamiser box.
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