Wanderer Motorhome Page 28

Contents:  CARVER WATER HEATER.

1.Frost Precautions-Carver Heater.  
2. Recommended Method of Use of the Carver Water Heater.  
3. Carver Water Heater Safety Warning. 
4. Controlling the Carver Water Heater Temperature and Adjustments 
5. Checking/testing for a Flame. 
6. Electrical Supply Notes, For Carver Heater. 
7. Gas Heater Faults and Fault finding. Repair hints.
8. Carver Cascade Heater Switch  Panel Switch Repair

This information is credited to Darren's site: www.faultfinder.freeserve.co.uk

As CARVER have been taken over by TRUMA here is an useful address:

TRUMA (UK) Ltd ,Truma House , Eastern Avenue , Burton-upon-Trent , Staffs ,DE13 OBB . TELEPHONE : 01283 511092

 

The "Faultfinder" is a site for those who would like to understand the workings of the Motorhome Heater. Darren has illustrated this in his web site.

 
Darren make's it clear if you don't have the skills, do not attempt repairs to electric and gas appliances.

I have included notes from my own experience, full information is recommended from Darren's site.

Carver Cascade MK 2
FROST PRECAUTIONS
IMPORTANT

When the Motorhome is parked for any length of time, especially during the winter, the CASCADE heater/ boiler should be drained to prevent frost damage.

This can be done by releasing the drain plug  as indicated by the arrow in the drawing I've prepared.  The drain plug need not be remove completely as prongs hold it position for draining. The drain plug can be left in this open position.  For ease of draining the small screw top left can be opened a quarter of a turn to release the vacuum. 

It is recommended to open all taps and and shower head, while draining, to release any created vacuum in the system.  The draining can be very slow and should be left for at least 40 minutes. 

In the illustration can be seen the Vacuum Release screw, this should be turned for a 1/4 turn until you feel it is tight. It is then open. Strange as it may seem the valve is locked when the screw valve feels loose

If your Motorhome has a filter system ensure it is empty.  This might entail the removal of the pipes attached to the pump to check. If you have a filter cartridge installed ensure this has no water inside.

When preparing the Motorhome for use.  Fill up the fresh water tank,  close all cold taps and shower head. Turn on the 12 volt electrics to operate the pump. Allow the hot taps to remain open.  When the hot taps stop spurting turn off, and  turn on the Cascade heater control panel.

Suggested Method for using Gas Water Heating: 

 Do the hot taps have a smooth flow?  Turn on the gas at the cylinder valve, and 12 volt supplies at the Main Control Panel.

Switch on the CASCADE wall control panel [Slide Switch above.]  Watch for the on GREEN lamp. Any other combination of lamps is a malfunction.

YELLOW and GREEN lamps on together indicate low battery volts. Turn on charger or engine to increase volts to panel. The Control panel switch will not turn on while the voltage is low.  This voltage level must be above 10.5 volts.

RED and GREEN lamps on together, after approximately 10 seconds,  indicate the gas burner has not been lit.  This could be due to the gas cylinder running empty, causing air in the pipes.  Check the gas at the cooker for gas. If gas at cooker then there could be air in the pipes.  Try and light the CASCADE again by switching on and off.  Allow about 5 seconds between each switching function if the gas bottle was empty and you've changed it.

IMPORTANT: If gas bottle is full you must wait 3 minutes for the gas to disperse before trying to light it.

Controlling the TEMPERATURE. 

The heater is set from the factory.  If the water is too hot, switch the heater off at the CASCADE Control panel and allow to cool.[ On my new burner, replaced due to a fault, it has no adjustment]

Remove the CASCADE cowl cover located on exterior wall, be careful of the drain plug when removing.

When cover removed you will see a loose cover at the top right, it indicates the heat level plus or minus.  Make small adjustments.

Place the cowling back in position but DO NOT tighten screws.

Switch on the heater and allow about half an hour to check for your required water temperature.

When satisfied, replace the cowling and remember to secure the 4 screws firmly. DO NOT over tighten and strip the threads.

The newer models are set at the factory and cannot be adjusted.

---

WARNING

All gas appliances should be switched off while travelling and in Ferries for safety sake.  We have all heard of the gas fridge flame activating at a Petrol station.

The Cascade 2 is a unique hot water producer.  It's usual image is the cowling of a balanced flue on an exterior wall of the Motorhome.

For maintenance the unit can be removed from the outside wall. During installation the builder should ensure that pipes and gas line has enough "Slack" to allow this removal.

The remote CASCADE 2 wall switch in the Autohomes Wanderer is located on the wall next to the kitchen unit, close to the side picture window.

See the above "Suggested Method" of use for the lamps in different conditions. 

Cold water is pumped into the Cascade 2 and hot flows out.  It is engineered with the hot outlet below the tank head to allow heat expansion.

It's advisable to ensure that the outlet pipe feeds a "Y" junction to kitchen unit and the shower, rather than a "T" Piece. This will ensure an easy flow.

The hot water control is automatic, The lamps do not indicate this condition.

The heater has two safety features. A pressure relief valve which will blow the heater contents into the cowling outside at 3 bar (44p.s.i). The other is a fusible plug should the heat be too great, the plug will melt and blow the heater contents on to the burner, shutting the heater down.  A red light should then show on the switch panel. The heater will then require workshop repairs.

www.arcsystems.biz The Carver Expert

           In the event of a gas leak, search for it using soapy water.

DO NOT US A NAKED FLAME.

If you can't find any gas leak, turn off the gas at the source and seek professional assistance.

The Cascade Water Heater has been built for use in the Motorhome or Caravan.

The mains water supply pressure is too great so must not be directly connected.

It has been developed for use with caravan pumps, with a pressure not to exceed 20psi [ 1.4 Bar.] Most pumps use 10psi. Check if replacing.

Sometimes the water can surge, if this problem occurs, a Whale Surge damper is recommended to eliminate pump hunting. [ See Motorcaravan Motorhome Monthly June 2000 page 186 ]
This part can be obtained from CAK, part No. 01926 854 271

The Cascade 2 water heater is designed to operate from a nominal 12v DC negative earth supply. This is usually provided by the leisure 12v battery.

The heater will continue to operate satisfactorily down to 10.5v to cater for reducing voltage as the battery becomes discharged. Below 10.5v the yellow light on the ZIG switch panel will illuminate and the heater will cease to operate until the voltage increases again. The yellow light may illuminate intermittently when the water pump is operating due to the high current consumption of the pump. This will cease when the pump stops.  In these cases the wire gauge must be increased to reduce the voltage drop. Low voltage may also be due to poor or corroded connections.

Both the positive and negative feeds to the wall switch are fused. Failure of the left hand (fused) fuse indicates a failure in the heater, failure of the right hand (negative) fuse indicates a problem in the earth bonding of the Motorhome itself.

There are no user serviceable parts within the electronic control box behind the burner. If the seal on this box is broken the guarantee is invalidated.

---

Note:

THE HEATER MUST NOT BE USED WITH BATTERY DISCONNECTED OR THE  USE OF A CHARGER ALONE.  THIS MAY CAUSE THE CASCADE 2 HEATER TO MALFUNCTION. 

GAS HEATER FAULTS

CARVER MK II

The advice can apply to the Carver Mk I in many instances.

The fault finding chart below assumes the reader is conversant with electrics and a voltmeters.

The Webmaster would like to stress that any information contained within this page and web site is as accurate as possible. He cannot accept responsibility for any errors on information posted in the pages on this site!

FAULTS	SYSTEMS	CAUSE	CURE
When switching on from cold. No indicator lamps come on.	Heater does not operate	Battery Power supply reversed. Power not reaching heater   Fuses not in place or blown	Check connection from Motorhome wiring to wall switch Check wiring from wall switch to leisure battery Check for reverse wiring faults, then replace fuses.
When switching on from cold, GREEN lamp ONLY comes on and stays on	Heater does not operate No fail lamp. ignitor not working,  Gas valve not working	Control Panel locked to on Multi-pin plug disconnected at wall switch or heater	Faulty control panel   Re-connect multi-pin plug
When switching on from cold GREEN and YELLOW lamps come on	Heater does not operate.  Battery condition low causing pump to run slowly.	Voltage measured at wall switch below 10.5Volts	Charge leisure battery or check and turn on charger. Check gas is turned, if turned on then pressure is too low to operate gas heater.[ Check pressure at cooker rings by flame height.]
When switching on, GREEN lamp comes on and after 10 seconds the RED lamp is on as well.	Listen to the heater during this period, a clicking sound will be heard. followed by intermittent ticking for 10 seconds.   Water coming from cowling   A click heard but no ticking OR ticking but no click If gas can be heard with burning hiss, then turns off.	Air in the Gas supply pipe. No Gas supply Incorrect gas pressure   Intake of flue obstructed  Pump pressure too high Poor connection at the multi-pin plug inside the wall switch or on the heater.	Purge gas pipe by switching on and off. Repeat if necessary. Check gas isolating valve and gas cylinder.   Check and clear.   This causes a voltage resistance, reducing supply voltage. Pull in and out to clean plugs
YELLOW lamp comes on when pump is operated	Pump runs slowly	Low leisure battery. [Possibly cable is too thin if this a new vehicle]	Check and charge the battery.  If fault continues, check the wiring.
RED lamp comes on after about 30-45 minutes, with water and steam from the cowling.	No continuous water flow from cowling when pump is running.[water taps on] Continuous water flow from cowling when pump is operated	Pressure relief valve operating on high temperature.   Fusible plug blown indicating thermostat failure.	Pump pressure too high.     DO NOT continue to use heater. Seek expert advice.
When switching on from cold, GREEN lamp ONLY comes on and stays on - usually a good condition	Heater/Boiler stays on continuously, producing hot water	Faulty switch control panel.	Seek expert advice, or replace the switch front control panel box.
	MAINS ELECTRIC OPERATED HEATER
Mains immersion heater does not operate	Indicator on isolating switch not alight	Motorhome not connected to site supply. RCD has tripped   Site supply not adequate, unable to supply current.	Check Mains supply, if not connected. Reset and try again. If continues to trip, Seek expert advice. Switch off, check with site warden regarding supply.
AC Mains immersion heater does not operate	Indicator lamp on isolating switch alight.	Thermostat malfunction. Over temperature thermostat faulty.	Switch off seek attention Check  red reset button and reset if possible. The red Reset button located at the back of boiler, inside boiler locker.

 When switching on from cold, GREEN lamp ONLY comes on, and stays on. This is a fault condition.

This was a fault which confronted us days before we were due to catch the ferry to Spain. The conclusion was the panel internally was faulty and required changing.

                Taking off the cover and checking the wiring I found the printed circuit board was permanently on. Producing hot water constantly. A phone call to the local Caravan Dealer and with the above photo taken with my digital camera, I was able to obtain a replacement.  Fitting the panel on confirmed the diagnostics and the boiler was now working normally.

             The printed circuit board basically  switches on, and off, the 12Volts to the boiler, while looking complicated serves no other purpose.  The LED lamps are powered from the Carver heater to produce fault conditions.

              I suspect Q1 is short circuit, I will investigate and repair at a later date.

Re: Carver Water Heater repairs
From: Steve Taylor
Date: 06/04/2003

Comments

Try this number. The guys name is Gary and is based in Nottingham but will use a courier service to get your faulty equipment to him and return it when fixed. He has loads of spares for carver equipment.
Mobile: 07901 544431  Tel: 01159 213175 

----- Original Message -----

From: "Richard Smith" 
To: <brian[at]ourwanderer.org.uk>

Sent: Thursday, June 19, 2003 8:44 AM

Subject: cascade rapide water heater

Dear Brian. 

I'm sorry to be a bother again but I cannot fathom how to get my cascade rapide water heater working on our "Wanderer".

I have tried and tried to work it out but so far no luck. It seems to work on electrical hook up on immersion, however trying to get ANY lights on the wall plate in order to use battery and gas is no go. I have had the wall plate off and changed the fuse (funny looking car fuse type 5amp)checked the fuses on the main control pad (Aux x2) Pressed the "on" button I don't know how many times and NOTHING. What's going (gone) wrong? do you know?

By the way, how do you (and more to the point, where do you) fit passenger seat belts, I don't have any but you mention that your "Wanderer" has some fitted.

Regards Richard Smith.

 

Hi Richard,

No bother and I am only to pleased to help another "Motorhomer" in trouble. Regarding your water heater. Have you had a look at my fault finding chart on: www.ourwander.org.uk/wan28.htm Gas Heater Faults and Fault finding plus Repair hints. On the same page you will see a complete write up of the Carver Control Panel and how I repaired this fault.

OK, The mains heater is quite separate from the gas and as you said it is working correctly.

I assume you are not getting any 12 volts to the control panel, as the gas is 12volt operated.

When you take the panel off do you have the correct voltage at the input. Is the positive on the correct tab. See the above web page to indicate this. If it's not the right way around, then the safety feature of the Carver will stop it working. This can happen if any work has been done to the electrics from the ZIG panel.

The lights for example will work any way around, positive to negative and negative to positive, when the cable is fitted to the lights.

I don't recall a fuse inside the Carver Control Panel! The panel takes it's fuse from the ZIG panel.

Again you will see this in my drawings and photos in www.ourwander.org.uk/wan28.htm page.

So Richard you must check the voltages are correct inside the Carver Control Panel, the one with two press buttons first.

So I state the obvious check the voltage inside the Carver Control panel.

If it's not there then check the wiring from the ZIG panel to the Carver two button Control Panel.

In my drawings you will see a chart of voltages you can expect inside this panel.

If the voltages are there, then this panel could be faulty. This can only be checked by replacement.

If that is OK, then we must assume the gas control panel inside the Carver heater is faulty. I am referring to the panel located inside the outside wall ventilating cover. This panel cannot be repaired, and will require a Caravan dealer for repairs.

If your volts are OK and you can hear the gas popping outside, as it tries to turn on, then this is due to the gas burner flame spreader, inside the Vent cover being faulty. The flame spreader becomes so rusty then it cannot do it's job and refuses to light up.  This repair is not too expensive.

Having checked the above and made use of the fault finding chart. Get back to me again and we will go from there.

Regarding seat belts. In my Motorhome they were fitted by the previous owner.

The brackets which retain the belts are quite substantial. [I'll get some photos into my web site illustrating installation. ]

Two sets of lap belts are fitted below the back wall bench, with the belts coming up from behind the bench.

The bolts which retain the brackets are drilled through the Motorhome base and then mounted on brackets which are secured to the chassis. This is a "Must" as the Motorhome base is just not strong enough to take any pulling force.

I don't know if they are legal but I'm sure they will retain someone in an accident.

I don't like lap belts as I have seen some horror stories on the TV regarding them. Rear shunts for example. But they do use them in an Aircraft!

Best Regards,

Brian