Hot Water Control

lenster

I am a newbie trying to sort out an answer for my hot water

and how it is controlled.







1) I recently had my oil service providers technician  tell  me that

the thermostat on my Bradford White "water heater" needed to be

replaced and that it is easy to do as it is not covered by their service

contract.  I agree but with some caveats. The Bradford White was installed

apx 8 years ago. Hot water is generated by my boiler (E.F.M.) ( the boiler was

my hot water source prior to Bradford White installation) and delivered to the

Bradford White (aquastat? indirect?)  The bradford white delivers to

wherever it is needed, shower, dishwasher, faucets, etc. ? I have never been

able to regulate the temperature on the Bradford White.  Water temp has

always been way too hot.







2) The thermostat on the Bradford White ( Apcom WH9 thermostat) has never

seemed to have worked.  I cannot get the water temp down below a scald

level. There are currently NO wires going to the single heating element. 

This suggests to me the Bradford White is merely a holding tank and water temp

is controlled by my boiler.  Is this the case?  All wiring diagrams

show wires attached to the heating element on the Bradford but dont know if it

should be that way in my case.  I called Bradford White and they said that

they couldn't help me.  Call a service tech.







3) This suggests that the hot water is generated and controlled by the

thermostat on my boiler, a Honeywell, with a High limit and a Lo limit with a

differential to be set between them.  Does the thermostat on the Bradford

call for the boiler to reheat which seems quite often throughout  the

day?  Every hour or so. Does the Bradford send cooled off water to the

boiler and its sensor then go off to reheat?







3) Should I just replace the thermostat ( I have a new TOD 59T to replace the

Apcom WH9) on the Bradford and just see what happens?  How would this

thermostat control water temp to my service areas.  All explanations and

help with this are greatly appreciated.  Does that thermostat on Bradford

control the outgoing water temps? Then how does it know to get reheated or more

hot water?  Confused on this process.  Thanks, Len

gennady

MIxing valve

You have to install mixing valve to temper water to for the domestic hot water usage. adjust it to 115-120F at faucet. set heater to 140F, to prevent legionella .

icesailor

Water Heater Controls:

Please post photos of the water heater, the boiler and related piping from the boiler to the water heater.

Is there a circulator on the water heater tank?

I do installs for this all the time and I never have this kind of problem. I think it is piped improperly. The only thermostat that might need to be replaced is the bottom one that runs a circulator. And if you turn it up and down, it should "click" at the temperature inside the tank. It is only a switch to run the circulator.

The boiler temperature should be set no higher than 150 degrees on the "operating" side with the high limit, 20 degrees higher. If the lower thermostat on the water heater is set to 120 degrees, the water in the top of the tank might be a little higher for a while but it should settle out.

Need more information on your system.