LEAKING ISOTEMP 4.2

[LEOCAT66]

We have an ISOTEMP slim square 4.2 heater which is leaking. I am talking a slow drip from the front at the bottom. Over a 24 hour period we have about a 3 or 4 oz. accumulation, which is being collected in a small drip pan in order to monitor the amount. It is so slight that the fresh water pump might come on once a day for a very short cycle to compensate. The leak seems to increase when the 110 power is turned on. The leak is fresh water, not engine coolant, and is very clean, no sediment, no corrosion, evident. We have removed the small gray plastic cover on the front, to check for obvious leaking fittings but found nothing. One or two of the six bolts housing the element was slightly loose and was tightened. In order to go further we will need to remove the large white plastic front cover, which will nessitate the removal of the heater and all associated attachments. Would like to know in advance if we would likely find any repairable item behind the cover. Thought about just cutting away the cover as it only seems to serve as dress up item.

I have searched the net for information on possible trouble shooting ideas, or break down views, with negative results. Has anyone run into this issue? The heater is about 7 years old, and works like new and produces clean hot water. A new one is many coins, and only this type will fit.

[senormechanico]

It might be coming from the pressure relief valve.

[LEOCAT66]

Originally Posted by senormechanico

It might be coming from the pressure relief valve.

Thank You, I am still searching for a diagram, but assume that the PR valve is behind the cover. The pressure in the system does not seem to be excessive and and I have noticed no change. That is a great suggestion and probably a reasonable fix item.

[LEOCAT66]

Finally found a breakdown on the heater which shows a clear picture of the items under the gray cover. Called ISOTEMP and spoke to a tech there, who said there is nothing much behind the large white cover and believes that it is the gasket related to the element. He does not understand why I do not see water around the gasket bolts or wiring connector nuts. Fear that there are welds behind the white cover related to the fresh water fittings and possible cracks around them.