Paloma problem

[hearingdog]

Normally very reliable unit has developed following problem:- Burner fires up ok when h/w tap turned on but then almost immediately closes down.,...almost as soon as it has closed down it then fires up again.....it will keep repeating thus while the tap is on. (pilot light remains lit ok). Can anyone throw any light on this problem for me?? Hope so! Thks.

[blackrose]

Normally very reliable unit has developed following problem:- Burner fires up ok when h/w tap turned on but then almost immediately closes down.,...almost as soon as it has closed down it then fires up again.....it will keep repeating thus while the tap is on. (pilot light remains lit ok). Can anyone throw any light on this problem for me?? Hope so! Thks.

 

What happens when you swithch the Paloma off and just turn on a cold water tap? Is the flow the same as it used to be or is the water pulsing?

Edited April 16, 2009 by blackrose

[hearingdog]

What happens when you swithch the Paloma off and just turn on a cold water tap? Is the flow the same as it used to be or is the water pulsing?

 

 

Flow seems to be unchanged from the usual.

 

Flow seems to be unchanged from usual.

[onthecut]

Normally very reliable unit has developed following problem:- Burner fires up ok when h/w tap turned on but then almost immediately closes down.,...almost as soon as it has closed down it then fires up again.....it will keep repeating thus while the tap is on. (pilot light remains lit ok). Can anyone throw any light on this problem for me?? Hope so! Thks.

 

Gas pressure low ?

 

Mike.

[Geoff]

There is a valve on them that cuts off the gas supply if the water pressure gets too low, sounds like its that playing up if nothing else has changed.

[Tony Brooks]

Normally very reliable unit has developed following problem:- Burner fires up ok when h/w tap turned on but then almost immediately closes down.,...almost as soon as it has closed down it then fires up again.....it will keep repeating thus while the tap is on. (pilot light remains lit ok). Can anyone throw any light on this problem for me?? Hope so! Thks.

 

 

Some instant gas water heaters have a small port feeding water to the top of the diaphragm. Funny things happen when this blocks. Some also have a conical strainer in the cold water inlet connector. The symptoms are typical ot this being blocked as they are of a badly scaled heat exchanger.

 

If the water flow from the hot tap is about normal I would go for the small port, but if the flow is reduced I would go for the strainer and then heat exchanger.

[hearingdog]

Some instant gas water heaters have a small port feeding water to the top of the diaphragm. Funny things happen when this blocks. Some also have a conical strainer in the cold water inlet connector. The symptoms are typical ot this being blocked as they are of a badly scaled heat exchanger.

 

If the water flow from the hot tap is about normal I would go for the small port, but if the flow is reduced I would go for the strainer and then heat exchanger.

 

 

Thks Tony - I will check these out (together with gas and water pressures as suggested by other members) but would be obliged if you could give me more information re the small port / diaphragm - where located, how to access, etc. Regards.

[Tony Brooks]

Thks Tony - I will check these out (together with gas and water pressures as suggested by other members) but would be obliged if you could give me more information re the small port / diaphragm - where located, how to access, etc. Regards.

 

I speak generically because the main instant water heater when I was working with black hands was a real Ascot. From memory you have to remove the diaphragm chamber from below the burner and heat exchanger and undo the ring of screws so it splits in half. Between two of the screws is a little brass tube insert that is cast into one half of the chamber and fits into a drilling in the other half. This is the thing that blocks. It is all so long ago that I might have got this completely wrong so for goodness sake see if you can get hold of a manual or parts list for the thing so you do not get involved with gas joints or damage anything.

 

 

Some have a sort of adjusting screw thing with a locknut screwed into the side of the chamber. I think some can be removed and are the little port I was on about and others might be adjusters to control the restriction between upper and lower chambers.

 

You might even find one of the control knobs alters the pressure drop across the diaphragm so try those first, but note where they started and return each to its original position if it makes no difference.

[RLWP]

Is your Paloma one of these Here ?

 

Richard

[Tony Brooks]

I speak generically because the main instant water heater when I was working with black hands was a real Ascot. From memory you have to remove the diaphragm chamber from below the burner and heat exchanger and undo the ring of screws so it splits in half. Between two of the screws is a little brass tube insert that is cast into one half of the chamber and fits into a drilling in the other half. This is the thing that blocks. It is all so long ago that I might have got this completely wrong so for goodness sake see if you can get hold of a manual or parts list for the thing so you do not get involved with gas joints or damage anything.

 

 

Some have a sort of adjusting screw thing with a locknut screwed into the side of the chamber. I think some can be removed and are the little port I was on about and others might be adjusters to control the restriction between upper and lower chambers.

 

You might even find one of the control knobs alters the pressure drop across the diaphragm so try those first, but note where they started and return each to its original position if it makes no difference.

 

 

Please go to the Paloma Problem question in Boat Building & Maintenance where someone has posted a link to how they repaired their Paloma. It is well illustrated and explained (so well done to them) but shows my description is outdated for modern Palomas. However it is a problem in the link between chambers.

Edited April 17, 2009 by Tony Brooks

[Rojja]

Please go to the Paloma Problem question in Boat Building & Maintenance where someone has posted a link to how they repaired their Paloma. It is well illustrated and explained (so well done to them) but shows my description is outdated for modern Palomas. However it is a problem in the link between chambers.

 

Tony, maybe this the link you mentioned is this one Draper's Paloma problem

 

Although the fault on mine was somewhat different to Hearingdog's, the page might be of some help to him.

 

As his main burner lights then extinguishes as the water flows through the heater, after checking the venturi holes, I'd have a careful look at the spring loaded water valve(s) in the water temperature control's body, which 'seem' to modulate the water flow being controlled by the position of the diaphragm.

 

I suspect that they are there to allow a increased flow of water when a hot tap is initially opened (burner unlit) if they're stuck the flow through the venturi would suffer causing the main burner to go out.

 

These comments are probably worth less than was paid for them.

 

Cheers and good luck,

Roger.

[hearingdog]

Please go to the Paloma Problem question in Boat Building & Maintenance where someone has posted a link to how they repaired their Paloma. It is well illustrated and explained (so well done to them) but shows my description is outdated for modern Palomas. However it is a problem in the link between chambers.

 

 

Thks for the info again Tony - especially the link to Draper's Paloma Problem.

I do not have a manual or a parts list unfortunately - does anybody out there know if anything is available online?

[johnjo]

Thks for the info again Tony - especially the link to Draper's Paloma Problem.

I do not have a manual or a parts list unfortunately - does anybody out there know if anything is available online?

 

Look at your PMs

 

John

[hearingdog]

Tony, maybe this the link you mentioned is this one Draper's Paloma problem

 

Although the fault on mine was somewhat different to Hearingdog's, the page might be of some help to him.

 

As his main burner lights then extinguishes as the water flows through the heater, after checking the venturi holes, I'd have a careful look at the spring loaded water valve(s) in the water temperature control's body, which 'seem' to modulate the water flow being controlled by the position of the diaphragm.

 

I suspect that they are there to allow a increased flow of water when a hot tap is initially opened (burner unlit) if they're stuck the flow through the venturi would suffer causing the main burner to go out.

 

These comments are probably worth less than was paid for them.

 

Cheers and good luck,

Roger.

 

 

Thks Roger - very usefull and well presented info which, together with with the rest, I will take with me for a weekend with my Paloma. I feel much more encouraged now about sorting the problem. I would find a manual / parts list usefull perhaps - do you know if something is available online? (My model is same as yours) Cheers.

[hearingdog]

Look at your PMs

 

John

 

 

Thks for your message - I'm new to this game!! Did you receive my PM to you?

[hearingdog]

Is your Paloma one of these Here ?

 

Richard

 

 

No it isn't...it's a Paloma PH-5-3F (Mk V).

[NBMike]

Try here

http://www.dawncraftowners.com/Paloma%20manual

Mike

[johnjo]

Thks for your message - I'm new to this game!! Did you receive my PM to you?

 

Just got it and have replied.

Regards

John

[hearingdog]

Well the problem is no more I am pleased to say. Gratefull thanks to all forum members who responded to my call for help - your comments, advice, etc was invaluable

 

In the event, I never did find what was causing all the trouble.....after checking the basics (water & gas supply etc) and confirming that these were ok, I removed and stripped down the unit allowing me to clean out the heat exchanger and h/e pipe (compressed air) followed by the water control valve. There was nothing obviously amiss (to quote Tony, nothing fell out and said broken) so it was a matter of thoroughly cleaning all passages, holes, etc and flushing thro' generally as outlined in "Draper's Paloma Problem" (what a usefull write up that is!) When reassembled and refitted it fired up fine and showed nothing of it's original tendancies - Back in business.

 

Over a 20+ year period my Paloma has never once let me down and, like many things that are "totally reliable", became very much taken for granted - apart from draining out before the winter layup it never really got any attention.....in future it will. It will go on my Preventative Maitainence list so that it remains "totally reliable" for another 20 years because, for those that are not aware of it, spare parts are as rare as hen's teeth. Good luck to all.

[Rojja]

Well the problem is no more I am pleased to say. Gratefull thanks to all forum members who responded to my call for help - your comments, advice, etc was invaluable

 

When reassembled and refitted it fired up fine and showed nothing of it's original tendancies - Back in business.

 

Thanks for letting us know that it turned out well, although it's a shame you don't really get to know what the problem was.

I bet when you got it back together and it came to life again, you were a very happy bunny.

Well done.

 

Roj.