Tankless hot water heater controller board not powering up when power is applied

[petehall347]

Re: Tankless hot water heater controller board not powering up when power is applied

i meant Expansion vessel .

[stj]

Re: Tankless hot water heater controller board not powering up when power is applied

it looks like a multi-element/vesel version of what i'v worked on.

lets check all the shit that fails!
so check the themal switches bolted to the main heater bodies,
then disconnect the elememts one at a time and check the reistance of the coil AND resistance to the copper body.

the most common failures are thermal switch failure and the element sleeve splitting causing rust to link the iron element to the outer grounded jacket.
this is actually a bit dangerous here because you arent using copper pipes - i would never be using pvc for hot water pipes!

[CapLeaker]

Re: Tankless hot water heater controller board not powering up when power is applied

Could be also simple as air bubbles.
I don't have fibre anything around here either. I can be happy having my cable internet that I had to get back then. Fast forward almost 20 years, now it would be impossible to get connected to that cable internet, because of the length needed for the run and to what cost.

[sam_sam_sam]

Re: Tankless hot water heater controller board not powering up when power is applied

element sleeve splitting causing rust to link the iron element to the outer grounded jacket.
this is actually a bit dangerous here because you arent using copper pipes - i would never be using pvc for hot water pipes!

I would agree with you about this however I have lived in this house for 20 years now and how my was plumbing was done I just added more to connect the tankless water heater to the house water supply

Unfortunately the plumbing pipes are under the concrete floor and I am not about to even begin to replace it unless it starts leaking and I have no other choice in the matter

I going to try the restrictors and see if this makes a difference or not or might have put a one way valve on the output side of the tankless water line to keep the temperature sensor from seeing the wrong temperature
Mind you this is only a educated guess to maybe going on but until I try this I would always wonder if could be an issue

[sam_sam_sam]

Re: Tankless hot water heater controller board not powering up when power is applied

Could be also simple as air bubbles.
I don’t have fibre anything around here either. I can be happy having my cable internet that I had to get back then. Fast forward almost 20 years, now it would be impossible to get connected to that cable internet, because of the length needed for the run and to what cost.

It would not be so bad if this cable/internet provider would not try to rip you off when the issue was on there end and not telling you that it was a system failure issue REALLY an update I got the charges reversed but I had to go to their customer service center to get it resolved and the sad part of this is I have had to do this several times in the past so it is getting very annoying to say the least

It could be air bubbles but my question is how if basically a straight through pipe with a heater element in the center of the tube so I do not know what would cause this unless the water company is having issues again because in the past we have had low pressure and sometimes it has lasted for months at a time so who knows

[redwire]

Re: Tankless hot water heater controller board not powering up when power is applied

Why is that valve partially closed on the bigger heater's inlet?
I would expect cavitation bubbles to be getting into the flow sensor's turbine and screwing it up.

Isn't the right spot to throttle this at the (load) the shower heads, not in or out of the heater?