Paloma water heater not heating up

[Karen Lea Rainey]

Thanks all,

The rusted up burner was replaced with a fully refurbed all singing and dancing, and working unit that looks brand new.

I have today had a reply from Paloma Bob together with the downloadable brochure including trouble symptoms.

From the brochure it says " if the burner fails to ignite "  no 1 check water pressure,   no 2 check for blocked vents and then check for dust, debris, rust, etc on the burner,  

As I can rule out the cleanliness of the unit, I guess it must be the water pressure.

The pump is a Fiamma Aqua 8  (production date 12 _ 16)  it is 1.5 bar producing 7 litres per minute. 

First thing on Monday I will be Checking on the  flow rate to make sure its producing that, then check the pre strain filter going into the pump for debris etc. I also checked the voltage at the pump it was 12.68 volts whilst not working, I will also check the voltage when it is pumping on Monday just in case this is the problem.

Will report back when I have more info. Thanks

 

[TheBiscuits]

Is there a switchover valve to choose between gas heater and calorifier?

 

Ours hasn't got a switchover valve, but there is a shutoff tap for both the calorifier and the heater.  If the calorifier tap is open there is not enough pressure for the Morco.  

 

Has it ever worked since you got the boat?

[MtB]

3 hours ago, Ex Brummie said:

No, The OP has a rusted up burner already was what I intended to point out. We must all read things differently.

 

A rusted burner that in the same post he explained has been replaced.  You must have not read that bit.

[Ex Brummie]

I would think pump pressure is borderline. How far away from the pump is the heater?

[Karen Lea Rainey]

The pump is about 15ft from the heater, but the pump also feeds the calorifier and bathroom sink, shower/ over 3/4 hip bath,

When the engine has been running for an hour the water in the bathroom sink / shower is hot. The kitchen / galley sink is not connected and so relies on the Paloma (presumably via a t piece on the way to the calorifier).

[Karen Lea Rainey]

Thanks "the biscuits" there is a shut off valve that closes off the bathroom sinks / shower, i will try closing that valve and see if the heater works independently.

[Richard10002]

If you think it's a pressure issue, can you increase the pressure from the water pump?

 

I had a similar issue with a Rinnai gas water heater when changing it from supplying the shower only, to supplying shower, handbasin, and kitchen sink. It worked fine supplying the shower only, and didnt work when adding the extra destinations.

 

Whilst there were lots of different thoughts here, eventually it was as simple as turning a screw on the pump which increased the pressure.

 

My pump is a Jabsco, and the pressure adjustment screw is under a blue cover on the end. Jabsco warn against making any adjustments, with the threat of voiding the warranty - my pump was out of warranty, so it didnt really matter. I nearly spent £40 or so on a new High pressure "regulator" for the pump, before discovering that turning the screw has the same effect

 

[ditchcrawler]

2 hours ago, Ex Brummie said:

I would think pump pressure is borderline. How far away from the pump is the heater?

Also the pressure will fall when the tap is opened and only climb to cut out pressure when the tap is closed

[MtB]

3 minutes ago, ditchcrawler said:

Also the pressure will fall when the tap is opened and only climb to cut out pressure when the tap is closed

 

The pressure is only relevant in a roundabout sort of way. It is the flow rate through the heater that creates the pressure difference across the diaphragm making it move and turn the gas flames ON. Not enough pressure sort of causes not enough flow, but the flow rate of the pump needs to be high enough regardless of the pressure it develops against a closed tap. 

 

 

 

Edited August 3, 2018 by Mike the Boilerman
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[Karen Lea Rainey]

Thanks to "The biscuits", I closed the stop valve to the calorifier  and when I turn the hot tap on at the Paloma heater it works perfectly, it must have been than the water pipe coming back from the cally  has little or no pressure. Anyway it works now so thanks for all your comments