water boiler

[Captain Nitromors]

Hi can anyone tell me why my water boiler runs hot water for about ten second then cuts out to cold then fires up splutters then cold again, i have filled the tank with water so enough water getting to it, really annoying any help would be great,

[bottle]

This water boiler, is it a kettle.

 

 

Bit more info required, make, fuel etc. not that I will be able to help you but others may.

[RLWP]

Una Paloma blanca?

 

Richard

[Captain Nitromors]

rinnai water heater it is

[RLWP]

I don't know a song for that one

 

Richard

[Higgs]

Hi can anyone tell me why my water boiler runs hot water for about ten second then cuts out to cold then fires up splutters then cold again, i have filled the tank with water so enough water getting to it, really annoying any help would be great,

 

Could be water flow volume. Is your pump a good un? Try opening the flow control to maximum and see if the flame stays in. The water will be cooler, though.

[bizzard]

A splutter sounds like air is trapped in it. If your tanks recently run out of water. If there's a drain plug fitting on it try placing a big bowl under it, turn the pump on to pressurize, turn pump off, undo plug and air might come spluttering out. Its best to replace the plug whilst the pump is running and the waters gushing out. You might have a bit of a fight with it though.

[Captain Nitromors]

thanks i will try that method later to see if works ta

[Captain Nitromors]

no joy still hot water cutting off ?

[MtB]

Sounds to me as though it's overheating and an overheat thermostat is turning the flames OFF, then it cools and the stat re-sets and turns them back On again.

 

This is quite possibly caused by water scale contamination in the heat exchanger.

 

Which Rinnai is it, and how old?

 

 

MtB

[smileypete]

Is this in a recently aquired boat, or has it worked OK before for you?

 

cheers, Pete.

~smpt~

[MtB]

Is this in a recently aquired boat, or has it worked OK before for you?

 

cheers, Pete.

~smpt~

 

 

An important question when it comes to fault diagnosis, and one often not asked.

 

 

MtB

[kendo]

Hiya..

 

We have a rinnai too, and experience exactly the same thing as the OP.

hot water for 10 seconds......pump kicks in...... Cold water......

 

 

recently fitted a brand new heating element, in case it was scaled up.

Didn't fix the problem.

 

Pressure out of the hot tap is "pants" (a pathetic piddle) compared to the cold tap.

Makes showering something of a challenge.

 

Our water pump has no adjustable flow setting. Looking to replace that next, maybe.

(Though cold water flow is perfectly adequate).

 

 

Sorry not to have any answers.

[MtB]

Hiya..

 

We have a rinnai too, and experience exactly the same thing as the OP.

hot water for 10 seconds......pump kicks in...... Cold water......

 

 

recently fitted a brand new heating element, in case it was scaled up.

Didn't fix the problem.

 

Pressure out of the hot tap is "pants" (a pathetic piddle) compared to the cold tap.

Makes showering something of a challenge.

 

Our water pump has no adjustable flow setting. Looking to replace that next, maybe.

(Though cold water flow is perfectly adequate).

 

 

Sorry not to have any answers.

 

 

 

And sorry to have all the same questions....

 

Beginning with: did it ever work correctly?

 

And, If it used to work fine, did the problem crop up suddenly or develop slowly over a period of time?

 

 

MTB

[smileypete]

Also what sort of shower mixer do you have, manual, thermostatic?

 

And have you checked any inlet strainers on the heater or shower mixer for limescale blockage?

 

cheers, Pete.

~smpt~

[cereal tiller]

I don't know a song for that one

 

Richard

You are lucky enough to have forgotten Renee and Renata's "Save your love for me"?

 

Different spelling,same sort of noise!

 

CT

[Tony Brooks]

Also what sort of shower mixer do you have, manual, thermostatic?

 

And have you checked any inlet strainers on the heater or shower mixer for limescale blockage?

 

cheers, Pete.

~smpt~

 

 

And the water heater water inlet. I think some of those have strainers in as well.

[smileypete]

 

 

And the water heater water inlet. I think some of those have strainers in as well.

 

Which is what I said. Worth repeating though

 

cheers, Pete.

~smpt~

[Tony Brooks]

Sorry, didn't read the whole thread.

[kendo]

And sorry to have all the same questions....

 

Beginning with: did it ever work correctly?

 

And, If it used to work fine, did the problem crop up suddenly or develop slowly over a period of time?

 

 

MTB

Hi Mike. It's always been "pants". Which I'm not sure is 'working correctly' or not.

It heats up the water for washing up, but standing under the shower has always been touch and go.

 

Edit: manual mixer taps. And pump descaled 'not too long' ago.

Edited May 7, 2014 by kendo

[smileypete]

Could connect it to a mains tap via a hose (only the heater, not the whole water system!!!) to see if it runs OK then.

 

If so then it kinda rules out the heater itself, I suspect a lot of these problems are down to pressure switch, pump wiring and plumbing issues.

 

Would have though a 10lpm pump should do fine IF the wiring is up to scratch, the pressure switch is OK, there's no blocked strainers or other restrictions throughout the system, etc etc etc.

 

Soooo....

 

Kendo,

When you run the cold tap fully open into a bucket or bowl of known capacity, how many litres per minute do you get?

When you run the hot tap fully open into a bucket or bowl of known capacity, how many litres per minute do you get?

When you run the shower mixer fully open into a bucket or bowl of known capacity, how many litres per minute do you get?

 

And if you have an accumulator, what pressure does it read with the pump on and taps closed?

Then what pressure does it read with pump off and taps open?

 

cheers, Pete.

~smpt~