TriangleTube HL-20, Руководство сервисного техника

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Excessive water temperature is usually the result of stacking within the water heater. Stacking is the occur-
rence of various water temperatures layering within the water heater with the hottest water in the uppermost
layer. This layering or stacking effect typically occurs during small draws of hot water (typically less than
25% of the storage capacity) which are long enough to create a call for heat on the thermostat, but are short
enough not to deplete the stored energy within the tank. Excessive stacking can occur when frequent short to
moderate draws are taken in quick succession. During this type of situation, the temperature of the domestic
water can approach the temperature of the boiler water.
REMEMBER: All water heaters (direct and indirect) will stack.
Reducing stacking within the tank
- Reduce the boiler operating temperature to 160ºF - 170ºF. This will limit the maximum domestic out-
let water temperature during high stacking water usage.
- Raise the thermostat sensing bulb higher in the drywell. This will reduce the frequency of thermostat
calls for heat during small draws of hot water. However, it will reduce the quantity of available hot
water during a deep draw by delaying the call for heat to the boiler.
- Reverse the boiler side piping. The older installations may have the boiler supply at the top of the
water heater and return at the bottom. Reversing the piping, supply at the bottom and return at the top
will:
a) Result in lower tank stacking by having the hottest boiler water closer to the cooler incoming
domestic water.
b) Reduce the effect of “thermal overshoot” after the thermostat call for heat has been satisfied.
c) Provide a more uniform hot water delivery temperature during moderate to deep draws (25% to
100% of the tank’s storage capacity).
Reversing the boiler piping will not affect the performance of the water heater.
Install thermostatic mixing valve
- Installation of a thermostatic mixing valve will provide an uniform delivery temperature with mini-
mal regard to water usage.
Recirculation Loop
- Installation of a properly sized recirculation loop not only provides prompt delivery of hot water, but
it provides circulation and mixing of the water within the tank.
Excessive Water Temperature
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