New Hot Water Maker, 99 degree boiler supply

iowaboy

We have had an electric boiler for 15 years. It supplies two zones of in floor heat, a heat exchanger for forced air, and 45 gallon hot water maker.  The hot water maker started getting too hot and leaking a few months ago, so we had it replaced last week.  

When the new hwm calls for boiler supply, sometimes the boiler heats to 99 degrees- the same temp as the in floor heat- rather than sending 160 degree water to the hwm.  The domestic supply gets cold.  We never had this issue with the old hwm.  

Did something get set improperly with the new hwm, or is there programming elsewhere that needs to be checked. 

neilc

can you post a general picture showing the boiler, hot water tank, and any controls so we can see what you have there,

and are you saying "sometimes" the tank only gets the ~99*,
and sometimes it gets the 160?
or always the 99* ?

iowaboy

I think maybe it has more to do with prioritization?  

This afternoon the water tank was 90, the thermostat on the hot water tank was calling for boiler supply, but the boiler was only heating to 99°.  We were away for a few hours, and got back this evening, and it was heated to 160 again, and the hot water tank is 130, which is where the thermostat is set.  

Before, four showers could run simultaneously with an endless supply of hot water.  This is not currently the case.

EdTheHeaterMan

Did you take a picture of how the old water tank was wired in? There is a wiring/control problem with the new water heater tank.

Larry Weingarten

Hi, Off topic and nit-picky... It would be good to extend the relief valve discharge down to six inches off the floor, so there is less risk of getting scalded.

Yours, Larry

neilc

sounds like domestic and heating temp setpoints are mixed up(swapped),
do you know your boiler controller?
do you have your manual?

iowaboy said:

This afternoon the water tank was 90, the thermostat on the hot water tank was calling for boiler supply, but the boiler was only heating to 99°.

We were away for a few hours, and got back this evening, and it was heated to 160 again, and the hot water tank is 130, which is where the thermostat is set.

Can you clarify the 160 and 130 ?
you saw heating water temp at 160 ?
and the domestic tank / domestic supply at 130?
what was your outdoor air temp?
where are you?